The short answer is no. But……(read below)

What is a non-reportable crash? There are two elements in determining if a crash is reportable apart from location (highways and traffic ways). Injury or vehicle damage to the extent that it requires towing.

Regarding location, private property crashes are ALL non-reportable because statutory mandates only apply to highways and traffic ways.

It is perfectly okay for drivers to exchange required information without police presence or response.

Should police respond to non-reportable crashes? In my opinion, yes, for several reasons.

Traffic collisions should be investigated to determine causation.

It amazes me how some police departments have a “don’t investigate” policy  for non-reportable crashes but have no problem writing traffic citations were no collision occurred? So if you blow a red light and do not cause a crash you get a citation. But if you blow the red light and do cause a non-reportable crash, no citation, just exchange information and be on your way?

Our department has developed a form to exchange information for people at the scene and provide a narrative which consists of basics like pre collision direction of travel, point of impacts and contact damage. We also indicate cause or violation?

Documents can be checked for validity.

Conflict between operators can be avoided.

Traffic can be safely diverted.

There are circumstances were a non-reportable crash would be prioritized low and depending on the immediate need for police resources, the non- reportable may not be attended for an extended period of time, but this is the exception and not the rule.

Hope this helps!

2011 in review

Posted: 12/31/2011 in Safety

The WordPress.com stats helper monkeys prepared a 2011 annual report for this blog.

Here’s an excerpt:

The concert hall at the Syndey Opera House holds 2,700 people. This blog was viewed about 27,000 times in 2011. If it were a concert at Sydney Opera House, it would take about 10 sold-out performances for that many people to see it.

Click here to see the complete report.

Tha Heist

Posted: 05/13/2011 in News

We here at BM would like to digress momentarily to introduce you to a new motorcycle manufacturer worthy of attention which will assuredly appeal to many, including myself.

What attracted me immediately to the bike was the classic ‘bobber’ design. As I gazed at the photos, admiring the bike, I silently wished I could have one, but for someone in my situation, the purchase of a new motorcycle was, well, just not currently affordable…until I heard the price!

What! A new bobber style motorcycle for about 3k, what gives? I started to think, “man, I could swing 3k, either buy it outright with no payments or put down enough where the payments would be very manageable.”

Get used to Clevelands because you are probably going to be hearing more of them. I would like to introduce you to Cleveland Cyclewerks. I had an opportunity to chat with the owner, Scott Colosimo, and can say his heart is definitely in the right place. An exciting innovator, bike builder, doing what others have said can’t be done. Here is a description of their company from their website:

Their philosophy is simply profound: build quality, beautiful bikes that are affordable and you can be proud to own.

So what nabbed my attention? It’s called “Tha Heist.” In my opinion a game changer. Here’s what it looks like:

Mention a heist to a law man and images of armed goons come to mind. However this Heist conjures images of adventures to come.

In what way is it a game changer?

1. It is very affordable

2. Built on a concept of small Displacement Engine (250cc)

3. Design

Price

The bottom line is how much? There are many motorcycles I would have loved to own but the price put it out of range for me.

“Tha Heist” sells for around 3k. Now take another look at the picture above and ask yourself, would you consider this bike for 3k? To be honest, I did not think I would be in the market for a new bike anytime soon given the current prices. Delightfully, I am now in the market.

Small Displacement Engine

This may not seem like an advantage but it is on a few fronts.

The smaller engine is going to give you outstanding gas mileage, which is currently a big deal.

They are lighter and will appeal to many formerly intimidated by large, heavy machines. You don’t see MSF courses supplying 1000cc plus bikes for their training courses, there is a reason for that.

The smaller engines really appeals to me for the fun factor and the commuter costs. One review I read boasted 77 mpg. I don’t know about you, but I have two vehicles I share with my wife that don’t get anything close to 20 mpg. At $4.00 per gallon, current price of fuel in our neck of the woods, this is a big plus.

To me, motorcycling is about the ride, not power. You know, the freedom, wind in your hair, etc. Don’t get me wrong, I have upgraded myself right out of currently owning a bike because of the lure of bigger bikes. I have been there and done that, now I want to go back to simple.

The last bike I owned was an 11o0cc, complete with a 6 year loan at high interest. After marriage and a few kids, my riding time diminished, and I felt compelled to sell rather than let it sit in the garage making monthly payments on it. While the bike did provide me with  euphoric mania, it also almost got me killed because I tended to  over-ride my skill level on that machine.

Thinking back now, I wish I still owned my first 650cc bike, which was paid for and suited me fine until tempted by the bigger more expensive bikes.

Large displacement engines are not necessary to enjoy the rudiments of motorcycling. I am at a point where I just want to cruise around and enjoy the sites. I really don’t need speed or more horsepower or big payments.

Maybe you or someone you know is in the same boat?

Design

I have looked for used bikes that don’t look nearly as good but are still out of reach for me financially. “Tha Heist” is a beautiful bike that I would be proud to own. In the less is more genre this bike delivers.

It is also designed to be highly customizable; see http://www.clevelandcyclewerks.com/customers-bikes/

 

The simple design and engine also means your scheduled maintenance isn’t going to gouge your pockets. You may be inclined to perform the maintenance yourself?

Final Thoughts

Now you know.

Cleveland Cyclewerks, an exciting alternative for beginners and experienced alike. A game changer with a bright future. Personally, this has given me hope of once again owning a quality new motorcycle without breaking me financially.

There is a heist occurring; it is in reclaiming what motorcycling should be at its core, no longer impeded by the current economy or state of affairs in motorcycle industry.

I would personally like to thank Scott and his partners for daring to dream and doing what many said can’t be done. He is making it happen, overcoming obstacles, doing what it takes to fulfill his dream and vision with the promise of good things to come. A vision which many will embrace.

There are other offerings by this manufacturer, be sure and check them out at http://www.clevelandcyclewerks.com/

Best wishes to Cleveland Cyclewerks.

Scott said they can now sell direct to consumers who do not have a local dealership.

For more information contact PIT Motors Ltd.

Update 5/27/2011:
My wife called me this morning on my cell and said, “when you get a chance, check the car, I left a gift for you.” What was the gift? An invoice from Pocono Cycle stamped PAID IN FULL. I am now the proud owner of a new Heist. Thanks Scotty for making this possible!

What is meant by clutch and de-clutch?

Clutch = engaged (rear wheel is coupled mechanically to engine)

De-clutch = disengaged (rear wheel no longer coupled to engine)

Squeeze clutch lever and engine operates without power being delivered to the rear wheel (de-clutch). Release clutch lever and engine engages rear wheel (clutch).

Two Schools of Thought (there may be more I’m not really sure)

  1. Disengage the clutch with the first instance of braking (rear wheel is disengaged from the engine).
  2. Leave clutch engaged as long as possible for shorter stopping distance by effectively using front rear and engine braking.

Use of the Clutch

Some riders clutch during emergency braking some riders declutch. It depends on how you were taught. During our basic police motorcycle training, we were taught de-clutch (rear wheel no longer coupled to engine) during braking.

Keep in mind, not every rider using the same technique is going to produce the same stopping distances. I was producing some great stopping distances because I was testing the limits of how much pressure to apply to the front brake. I was the only rider to produce the shortest stopping distances. I was also the only rider to low-side from locking the front wheel (not recommended).

In 2004, the Promocycle Foundation published “Task analysis for intensive braking for a motorcycle in a straight line.On page 9, the very subject was tested. The thought there was a rear wheel remaining coupled to the engine is less susceptible to lock.

The mean (average) braking distance recorded over 35 passes with the clutch engaged was 41.51 metres (136 feet).

In the 11 passes for which the rider was instructed to declutch, that is to pull the clutch lever and disengage the rear wheel from the engine, the mean (average) stopping distance was 39.95 metres (131 feet).

The rest of the report is an interesting read if you want to look at it click on the link above.

Conclusion

As part of our investigations we often take plenty of photographs (thanks to digital cameras). People want to know what kind of camera we use or what is the best camera to use. My response is always the same, the best camera in the world is the one you have with you.

When you need to take a photo, like right now, the $5,000 Nikon back at the office is of no value. In that situation my iphone camera is the best camera in the world.

Emergency braking is similar. What is the best technique in the world? The one you have with you, or rather, the one you are familiar with. The one you have practiced is going to yield the better stopping distance for you.

Whatever you choose or feel comfortable with is the right technique for you. Practice, practice and then practice some more.

In this post I want to talk about a speed as a hazard, particularly speed variance. Motorcyclists should learn the effects of posted speed limits have on the motoring public and when these situations present a hazard.

Years ago I was asked to speak to a private community association group. What was their number one complaint, speeding! The crowd was getting hostile about too! Then I asked, “who in the room has never broken the speed limit?” One lady answered and quickly said, “me…but I don’t drive!”

The most basic speed law throughout the country is very similar, see below.

PA Basic Speed Law

§ 3361.  Driving vehicle at safe speed.
        No person shall drive a vehicle at a speed greater than is
     reasonable and prudent under the conditions and having regard to
     the actual and potential hazards then existing, nor at a speed
     greater than will permit the driver to bring his vehicle to a
     stop within the assured clear distance ahead. Consistent with
     the foregoing, every person shall drive at a safe and
     appropriate speed when approaching and crossing an intersection
     or railroad grade crossing, when approaching and going around a
     curve, when approaching a hill crest, when traveling upon any
     narrow or winding roadway and when special hazards exist with
     respect to pedestrians or other traffic or by reason of weather
     or highway conditions.


“Reasonable and prudent under the conditions” is pretty much universal. All other posted speed limits should be based on traffic and engineering studies. There are many other factors to consider when setting speed limits, like:

  • crash history
  • grade
  • alignment
  • shoulder condition
  • intersection spacing
  • amount of traffic
  • type of traffic
  • sight distance

These conditions may cause speed limits to be set lower than the 85th percentile speed (explained below). In every event, the lower speed should be posted in 5 mph increments as near to the 85th percentile as possible.

Note: 85th percentile speed is determined by free flow traffic (in other words, cars traveling unrestricted)

On Speeding

In some communities, speed limits are notoriously set lower  because of public pressure to reduce speeding. Pennsylvania allows municipalities to set speed limits at 25 mph without a traffic and engineering study in a residential district that is not a numbered traffic route and is classified as a local highway.

But does this tactic really work? Why do most people exceed the speed limit anyway?

A major issue is when the posted limit is much lower than the 85th percentile speed. In every event, with the exception noted above, traffic and engineering studies should be down to establish safe speed limits. The said truth is that many roadways are posted without traffic and engineering studies and therefore may be improperly posted with very low limits without warrant. This type of speed posting will create many violators and tax police efforts to enforce the law.

We have several residential streets that are posted 15 mph that no one obeys! It’s too low to be taken seriously.

Are slower posted speed limits safer? Not always.

The Plain Truth About Speeding

Have you ever heard of the 85th percentile speed? This is the speed at which 85 percent of  drivers will drive at or below. In other words, the majority of drivers will adjust their speed to what they feel is reasonable and safe. This is commonly referred to as the 85th percentile speed.  Speed limits should be set as close to the 85th percentile as possible, with due regard for other factors (sight distance, grade, alignment, etc.).

Exceeding the posted speed limit, in and of itself, is not the whole story. The variance in speed created by lower speed limits is more likely to create conflicts and hazards.

You can travel at very high speeds in a limited access highway with little potential for conflict because everyone is traveling in the same direction and are going relatively fast also. When does the hazard occur on a limited access highway? When cars are traveling slow. Some limited access highways have minimum speed limits, usually around 40 mph.

Have you ever heard about the 10 mph pace or “pace speed”? This is the highest percentage of vehicles traveling in a 10 mph speed range (i.e. 30 to 40 mph). This method helps determine if the speeds are uniform. The lower the percentage of vehicles traveling within the 10 mph pace the greater the speed variance, which results in decreased safety.

If the posted limit is lower than the 10 mph pace speed, many drivers will ignore the signs and continue to travel at higher speeds. Some drivers will travel at the posted speed limit or close to it.  When vehicles travel at different speeds, this variance in speed causes problems such as tailgating, illegal passing and congestion.  Prolonged periods of time in these conditions can lead to aggressive driving and the increased likelihood of some form of “road rage.”

Posting speed limits at near the 85th percentile actually:

  • Increases safety
  • Makes for easier enforcement –  Blatant speeding is easier to identify
  • Safe drivers are not penalized
  • Police Officers are not wasting time enforcing arbitrary or unrealistic speed limits

Conclusion

Remember, the rider/driver should always make speed adjustments based on the actual road conditions, which change frequently. You should always be able to stop within the distance you can see to be clear or the assured clear distance ahead.

Recognize roadways which have a potential for speed variance and treat this segment of road as a potential hazard. Also recognize roadways that have posted speed limits that appear to low. A particular area of conflict to watch for is multi-lane roads with low-speed limits and vehicle attempting turns or lane changes. The faster over-taking vehicle may be driving faster than his ability to stop AND NOT be perceived within the available sight distance of other vehicles.

Important:  PLEASE note we are not advocating exceeding speed limits in any way, shape or form. We advocate understanding that low-speed limits will increase speed variance and make that segment of road more at risk for crash.

I have investigated more motorcycle fatalities in 25 and 35 mph zones than in any other posted range.

I hope this post gives you a little insight into recognizing speed variance as a hazard.

You can normally spot a fairy tale from afar. It starts like this, “Once upon a time, in a land far far away…”.

For motorcycle crashes it starts like this, “Yep, I had to lay her down…”. Immediately what follows is fiction. It is amazing to me how many people have employed this tactic they never practiced or were ever taught (sarcasm).

“Laying a bike down is never a plan, it is a consequence.”

Laying a bike down is never the plan of any rider, it is the consequence of failed braking. You over-braked your rear and induced a slide-out. You did not plan this, but this is what happens most of the time under panic braking because under stress you will slam your brakes.

For those who might want to cling on to the fairy tale that laying a bike down is a viable technique, answer these questions…

Where or how did you learn to lay your bike down?

What training is available for this technique?

Who teaches this technique?

How often do you practice this maneuver?

In other words, in the precious 2 seconds you have to decide what evasive action to take you’re going to rely on an induced impact (you and your bike hitting the pavement) which you never practiced, which will produce a much longer stopping distance and a higher impact speed, not to mention loss of control, because somehow you rationalized this was the best possible outcome?

Come on riders lets educate not propagate. Don’t let anyone say this to you without a challenge.

Metal/plastic sliding on the pavement has a much lower frictional value than rubber, you are going to slide a much longer distance. Even if impact is imminent, you would do better to minimize injury by scrubbing off as much speed as possible by braking before impact.

“The stopping distance you trade off by sliding on your side could easily mean the difference between crash or no crash.”

The fact of the matter is the trade-off in distance may mean the difference in crashing or not. For example, if you are traveling 50 mph and slide to a stop on your wheels on a well traveled, level asphalt paved road your stopping distance is going to be about 104 feet. Now, if you slide to a stop on your side, the stopping distance is going to be about 185 feet. The 81 feet difference is what we are trading for, easily the difference between colliding or not.

The one thing we have to mention is that you are already in trouble because you failed to compensate for an impending hazard, not casting stones I have failed many times as a rider myself but let’s call it what it is. Don’t compound your troubles by losing control of your bike. All kinds of nasty things can happen if you slide-out.

It is important to note that braking alone will not cause you to slide-out. It is possible to lock up your rear tires and not lay the bike down. You can ride it out:  http://bettermotorcycling.wordpress.com/2009/05/03/how-to-ride-out-a-rear-wheel-skid/ …or ride it out until impact if that is your situation.

Riders will crash for two reasons:

1. Failed to detect hazard (reaction time)

2. Lost control of the bike

Both are elements of training necessary for surviving the mean streets.

If you truly believe you successfully deployed a “laying it down” maneuver to avoid  a crash or minimize injury I’m willing to hear about it. But expect to be challenged.

Last year, about November, I almost hit a teenager darting out into traffic. The conditions were:

  • Night time
  • Street lights (spaced over 150 feet apart with dark spots in between illuminated areas)
  • Straight road
  • Mid block
  • No adverse weather

I was on duty, on regular patrol, heading into the center of town. I noticed a group of about three or four teens on the sidewalk on my left (sort of goofing around). I was probably doing about 30 mph.

Suddenly, a teen emerged directly in front of me from the dark spots in between the street lights illuminated range and on the outer edge of my headlight illuminated distance ahead.  She stopped in the middle of lane and froze like a deer.

I did not anticipate this and found myself grabbing a handful of brake. Both front and rear. As is typical, even among the well trained, when it is panic time, riders will generally lock the rear wheel, and I did.

I found the rear slide out a bit but I just kept looking straight, kept my arms locked out straight and rode it out.

I literally missed hitting her by inches. Did that get the old heart pumping!

She was distracted by her friends, stepped out into the roadway, never looking. I had a chat with her about would could have happened given a couple of seconds either way. I don’t think she’ll make that mistake again but what a way to learn.

Thinking back on it, I should have identified the group on my left as a hazard and started to slow down (the purpose of slowing down is to buy more time). This may have prevented the need to emergency brake.

Points to Ponder

As stated in the previous post, dart-outs are the most common pedestrian mistake.

Understand the additional hazards that night time riding presents:

  • Dark spots between illuminated street lights
  • Limited peripheral vision
  • Limited illuminated distance ahead on your bike (about 150 feet)
  • Less contrast

Kids (teens) congregating in small groups should be classified in your plan as a hazard. Slow down to buy time (time is your friend).

It is better to over compensate than to find yourself in emergency panic mode.

If you do have to panic stop, how good is your muscle memory. If you have not practiced this technique then it probably will be absent when you need it. Thousands of miles of riding will not prepare you for the emergency braking.

Even I found myself over-braking my rear tire. Quick review of emergency braking technique:

  • Grab clutch, cutting off power to engine
  • Squeeze front brake, front of bike will start to dip
  • Keep your right foot on the rear-brake, do not add any additional pressure (easier said than done) the dipping forward motion from the front brake will cause your right leg to depress brake pedal (if over-braking the rear occurs, do not release the brake, just ride through it)
  • Keep your head up and eyes straight, do no make direct eye contact with impending hazard
  • Keep your handle bars straight, arms locked out

Remember, even if a pedestrian made eye contact with you, they notoriously under estimate approaching speed. They will probably opt to cross regardless. If it is at night time, they think the distance they can see you is the same distance you can see them.

This was a frightful reminder to me, even though it turned out well. The plan is always to detect hazards with even time for you to react so you don’t find yourself in a panic situation. The better you can do this, the safer your riding will be.


Understanding the mistakes pedestrians make can better prepare us to avoid them. The following mistakes are a result of my own independent investigations of pedestrian collisions over the last 22 years in rural PA.

1. Dart outs

When riding, it is wise to treat pedestrians as potential hazards, especially the younger ones who are prone to dart out into traffic (however, older pedestrians are also capable of leaving the sidewalk suddenly, stepping into traffic which is so close as to constitute a hazard).

While the primary symptom of this condition is inattentiveness, there are other factors such as:

  • misjudging speed of approaching vehicles
  • view obstructions from stopped or parked vehicles
  • distracted by multi-lane roadways (negotiating approach from several vehicles from opposite directions and slower vehicles being overtaken)

Watch for the group crossing together and the straggler trying to catch up. This configuration presents itself often.

Also, dart outs are likely to occur mid-block, usually between vehicles.

2. Erroneously believing they have the right-of-way

Pedestrians of this type will step into traffic with the sincere belief that vehicles will automatically yield to them. They are not thinking about a vehicles ability to stop. The combined inattentiveness of the pedestrian and vehicle places them at high risk for collision.

In Pennsylvania, pedestrians only have the right-of-way crossing at crosswalks and intersections (absent traffic-control signals).

§ 3542.  Right-of-way of pedestrians in crosswalks.
        (a)  General rule.--When traffic-control signals are not in
     place or not in operation, the driver of a vehicle shall yield
     the right-of-way to a pedestrian crossing the roadway within any
     marked crosswalk or within any unmarked crosswalk at an
     intersection.
§ 3543.  Pedestrians crossing at other than crosswalks.
        (a)  General rule.--Every pedestrian crossing a roadway at
     any point other than within a crosswalk at an intersection or
     any marked crosswalk shall yield the right-of-way to all
     vehicles upon the roadway.

If the intersection is controlled by traffic-signals, it’s cross at the green, not in between.

If the intersection is controlled by pedestrian traffic control signals, this complicates the issue because now the pedestrian must obey the particular pedestrian traffic signal (you know, hit the button on the pole and wait for the walk symbol to flash) and most don’t.

I conducted a small study one time when we were asked to check for vehicles at a busy intersection running the red light. The intersection was also controlled by pedestrian control signals. What we found was the pedestrians crossing against their signal was much more prevalent than vehicles running red lights. During a one hour period the ratio between pedestrians failing to cross at a walk signal and cars failing to stop at a red signal was 7O:1. The pedestrians were a much more prevalent safety issue. Not what the boss expected but prompted some thinking.

3. Crossing at an angle

This type of mistake causes problems for the pedestrian because whether they realize it or not, they are in the roadway longer. More time crossing the roadway, especially mid-block, increasing the probability for conflict.

Just like motorcycles present a relatively small profile because of their size, pedestrians are even smaller. That means that they are more likely to be missed if there is not sufficient contrast between them and their background. Conspicuity is aggravated further when crossing at an angle depending on sight-lines.

Motorcycle riders have an advantage over most cars because they sit higher (better visibility) and do not have to contend with “A” pillar blind spots inherent in automobiles.

4. Walking in roadways with their backs to traffic.

I can’t tell you how many times this occurs on PA roads. Most roads do not have sidewalks or even shoulders for that matter. Absent sidewalks and shoulders the pedestrian should walk against the flow of traffic. It is amazing to me how trusting pedestrians tend to be. They won’t even look up at an approaching vehicle. They don’t consider crests and curves with the limited sight distance. Here is what the vehicle code says about walking along or on the road:

 § 3544.  Pedestrians walking along or on highway.
        (a)  Mandatory use of available sidewalk.--Where a sidewalk
     is provided and its use is practicable, it is unlawful for any
     pedestrian to walk along and upon an adjacent roadway.
        (b)  Absence of sidewalk.--Where a sidewalk is not available,
     any pedestrian walking along and upon a highway shall walk only
     on a shoulder as far as practicable from the edge of the
     roadway.
        (c)  Absence of sidewalk and shoulder.--Where neither a
     sidewalk nor a shoulder is available, any pedestrian walking
     along and upon a highway shall walk as near as practicable to an
     outside edge of the roadway and, if on a two-way roadway, shall
     walk only on the left side of the roadway.
        (d)  Right-of-way to vehicles.--Except as otherwise provided
     in this subchapter, any pedestrian upon a roadway shall yield
     the right-of-way to all vehicles upon the roadway.

5. Night time crashes – they can see you so they assume the driver or rider can see them.

The pedestrian can easily see an approaching vehicle from a large distance away. So they assume the driver can see them. They don’t understand that the illuminated distance ahead an a vehicle is only about 150 feet (300 with high beams).

Most pedestrians wear non conspicuous, non reflective clothing. At night-time this is a compounded problem for obvious reasons. They also don’t understand it can take up to 3 seconds at night for a driver to react to a hazard.

Keep the above factors in mind in your riding plan and compensate accordingly.


2010 in review

Posted: 01/02/2011 in Safety

The stats helper monkeys at WordPress.com mulled over how this blog did in 2010, and here’s a high level summary of its overall blog health:

Healthy blog!

The Blog-Health-o-Meter™ reads Wow.

Crunchy numbers

Featured image

About 3 million people visit the Taj Mahal every year. This blog was viewed about 33,000 times in 2010. If it were the Taj Mahal, it would take about 4 days for that many people to see it.

 

In 2010, there were 19 new posts, growing the total archive of this blog to 140 posts. There were 19 pictures uploaded, taking up a total of 2mb. That’s about 2 pictures per month.

The busiest day of the year was March 29th with 1,881 views. The most popular post that day was What went wrong?.

Where did they come from?

The top referring sites in 2010 were alphainventions.com, reddit.com, ridethree.com, Google Reader, and roadcaptainusa.com.

Some visitors came searching, mostly for ape hangers, motorcycle stopping distance calculator, ipsga, and motorcycle stopping distances.

Attractions in 2010

These are the posts and pages that got the most views in 2010.

1

What went wrong? March 2010
20 comments

2

Close Call With Ape Hangers July 2009
14 comments

3

Ski-Doo Modular 2 Helmet Review March 2009
3 comments

4

How to Ride Out a Rear Wheel Skid May 2009
11 comments

5

Double Yellow Line – Driving Manual and Law Conflict May 2010
3 comments

Note: Video said rider was traveling at 120  kmh = 74 mph = 108 fps (feet per second)

This video is helpful in identifying hazards and observing collision dynamics, a few observations:

1. Road configuration should have alerted rider of impending hazards; tree-line across median, left hand curve approaching intersection with left turn lane. The correct strategy would have been to match his speed to the current conditions to allow time to react.

2. Low light conditions; while we do not know the time of the crash and while it is difficult to assess on the video footage to tell how bright it was, it appears every vehicle had on their headlights and the roadway appeared dry (so no adverse weather conditions). If this was the condition, it  could have actually helped the rider detect the turning vehicle. As the turning vehicle is crossing, the illumination from the headlights would shine across the road.

3. Rider’s speed is a definite factor; notice the motorcycle did not appear to be within the field of view of the left turning vehicle when he executed his turn.

4. Rider’s target fixation; had the rider stayed in his lane and kept his approach line, even at 74 mph it appears he would have avoided the car. The rider was traveling in the left lane and the point of impact occurred in the right lane.

5. The three left turning vehicles opposing the car driver present a significant view obstruction.

6. It appears the rider had probably at minimum 5 car lengths (about 75 to 100 feet) when he detected the encroachment and starts to steer to the right toward the direction of the moving car.

He was toward the right side of his lane, a simple counter-steer (push left go left) to move to the left of his lane would have been a successful evasive move (not so simple at 74 mph). However, generally it takes about 2 seconds to complete an evasive maneuver so in this case there may have not been enough time at the speed the rider was traveling.

7. Braking was not an option: 

At 74 mph you need about 240 to 260 feet stopping distance (if you achieve 100 percent braking, that is, which many riders do not); and that is not accounting for perception reaction time/distance (generally 1.6 seconds or an additional 172 feet); the total stopping distance for 74 mph is about 412 feet.

While the readers of this blog would never allow themselves to be placed in this scenario, it is interesting to see the sequence of a collision from pre-impact to final rest unfold.

Harley 103 and 110 Woes

Posted: 09/01/2010 in Uncategorized
Tags:

If you have a 103 or a 110 engine and you have experienced significant loss of power you might be the victim of a bad ECM update download.

I took the police 09 Electra Glide (103) in for its 15,000 mile service. When I got it back I noticed a loss of power, very prevalent on uphill incline.

I took the wheel back to the dealership and they tinkered with it for about 3 weeks to no avail. Finally on the second call to Harley HQ, the tech was confident it was a recent download to the ECM causing the problem.

The bikes ECM was shipped to Harley HQ where it was “reflashed” and returned.

Problem solved. My understanding is in only affects the 103′s and 110′s.

1. Failing to detect hazards

Untrained riders will normally NOT develop appropriate scanning techniques which is critical to accident avoidance since the more time you have to react the more favorable the outcomes. Or they completely fail to recognize a hazard and therefore make no adjustments to provide an escape.

The sad reality of motorcycling is you are less conspicuous than larger vehicles and often your ability to avoid hazards depends on your awareness in traffic situations that you may be invisible to other road users, which will definitely require adjustments on your part in speed and lane position.

2. Over-braking the rear

Would you drive your car with only 30 to 40 per cent braking available?

Our investigations show untrained riders continually over-brake the rear often to the exclusion of the front brakes. Obviously this will increase your stopping distances and chances of a collision. Many riders don’t even recall whether they applied any front braking at all. That tells me they don’t incorporate the front brakes regularly to develop muscle memory, which will reveal itself under stress or emergency situations.

Furthermore, if you don’t properly ride out a rear brake lock up two worse things can occur. You will induce a slide-out, again, increasing your stopping distance because know your sliding on metal or worse if you release the rear brake while the bike is leaning you can induce a ‘high-side’, which is worse because you get launched off the bike into the path of whatever happens to be in the way.

3. Curve negotiation

The following errors are the most prevalent:

a)  Coming into a curve to fast – this is caused mostly by riders failing to recognize the severity of the curve, riders will usually opt to apply brakes while leaning to reduce speed which inevitably will create a loss off traction

b)  Failing to look through the curve (often staring at an obstacle) – many riders hit fixed objects off the roadway while negotiating curves; this is attributable to becoming fixated on a target which will widen your line (you tend to go where you look on a motorcycle)

c)  Failing to maximize lean angle for the speed – many riders fail to utilize the available lean angle necessary to carry them through the curve at the selected speed; there is the occasional leaning too much and exceeding the available lean angle; often excessive leaning is a fall-back tactic to compensate for excessive entry speed.

c)  Applying brakes while leaning – cornering places a demand on your available traction; riders that choose to brake while cornering exceed the available traction; again, often as a poor fall-back plan for inappropriate entry speed.

d)  Line selection – riders choose a line through a curve that carries them across the centerline or are to close to the center of the roadway placing them in the path of an approaching vehicle which may me over their centerline.

4. Steering

Often in our investigations, it appears the rider turned into a vehicle when they could have easily steered around it. Or they fail to take any evasive move whatsoever when a swerve could have avoided a collision. Or they run over an obstacle that could have been avoided.

We attribute this mistake to lack of counter-steering knowledge. Motorcycles traveling at speed have precise steering input only if applied correctly. It is the opposite of slow speed steering. In a parking lot, if you want to turn right you push forward the left handle bar (right handle bar comes in nearest the rider) and you turn right. At speed to turn right you do the opposite. To swerve you push forward on the right handle bar which induces a lean to the right.

You can imagine the problems a rider has if he is pushing left when he is intending to go right.

5. Failing to train

We feel failing to train is a big mistake and worthy of the top 5. Many crashes occur with unlicensed, untrained riders. Many crashes would be avoided if only the basics were applied. Unlicensed and untrained are over-represented in crashes. This is a horrible mistake because motorcycle crashes can be very unforgiving. I know several riders that have lifetime disabilities and loss of limbs attributable to their inexperience.

Inexperience always leads to riding beyond your ability.

Top 5 Mistakes: Cars

Posted: 08/17/2010 in Uncategorized

I was recently asked what are the top 5 mistakes drivers make and I thought it was necessary to break it down even further to cover the majority of contributions to crash causation.

  1. Cars
  2. Motorcycles
  3. Teen Drivers
  4. Pedestrians

In  this  post we’ll cover cars. This is not based on any national statistics but my own experience investigating crashes in the Pocono area of PA for past 21 years.

NOTE: There is a caveat to the top 5 mistakes and that is driving while drowsy/fatigued. This factor alone may far exceed all other mistakes combined but is the most difficult to identify because drivers do not understand the effects of fatigue and the forms of impairments it may cause.  Since drivers will not readily admit or understand fatigue and its effects it is not included in the list but may very well contribute to all driving mistakes to some degree.


Car Drivers Top 5 Mistakes

1. Driving while distracted

Quite simply, drivers are looking away from the forward motion of their vehicles at the onset of a collision. There are many reasons why drivers attention is diverted but basically anything that removes your eyes from the road ahead is a distraction. Remember, time equals distance. If you are traveling at 40 mph and you divert your attention for just 1 second to looking at who just called you on the cell phone, you traversed about 60 feet while you were looking away from the forward motion of your vehicle; two seconds 120 feet and so on.

Multi-tasking while driving is emerging as a serious distraction and responsible for many collisions. Many States are passing laws restricting cell phone usage while driving. While the cell phone naysayers are quick to point out other distractions while driving, in my opinion they are not on the same plane. The cognitive input required to send a text message or carry out a conversation is more engaging than turning the dial on a radio or applying make-up.

The additional hazard to this type of activity is that you may be actually looking forward but you are so disengaged from the driving task that you miss potential hazards arising, like someone slowing to turn or completely stopped in your lane.

2. Speeding

There are two sides to every story (well really three, your version, the other person’s version and the truth, lol). Speeding is problematic but not for the typical reasons people think about. Exceeding the posted speed limit is just one side of the story.

On a limited access highway (freeways, interstates, etc.) what is the speed you expect most people to travel? 60, 65, 70 mph? If a vehicle is traveling at 30 mph it is the variance of speed that is presenting the hazard? As a matter of fact PA requires the use of hazard signals traveling at less than 40 mph on limited access highways.

Speed limits signs posted significantly below the 85th percentile speed may further contribute to speed variance related problems. What is the 85th percentile speed? Simply the speed at which 85 per cent of the vehicles are traveling at or below.

I have seen many municipal governments cave in to public demand and post unreasonable speed limits in an effort to reduce speeds (typically in a residential neighborhood); resulting in greater variances, which is more hazardous. Most drivers will not comply with unreasonable speed limits or stop signs placed without warrant simply to reduce speeds.

10 MPH PACE is a term used in analyzing traffic flow. The greater the percentage of vehicles traveling within a 10 mph pace the less hazardous.

The goal should be to determine 85th percentile speeds for different segments of roadways and adjust posted limits accordingly. This type of posting will help keep speed variances in check and make the road less hazardous.

3. Following Too Closely

The simplest thing to correct but the one most overlooked.

Following a vehicle (keeping pace) with less than 2 seconds is the most common mistake. Many sources are now recommending up to 4 seconds but that may not be attainable in many driving circumstances.

If you fail to maintain a two second minimum following gap you will not have enough time/distance to react. Remember, it is your responsibility to be able to stop your vehicle within the clear distance ahead.

4. Failure to yield

Many drivers are not respecting the right-of-way of approaching vehicles. The problem is further enhanced by ignorance to the inherent view obstructions (blind spots) created by vehicle pillars (A, B and C pillars).

The most frequent right of way violations on the roadway is the left turning vehicle, followed by proceeding without clearance at a stop sign.

In parking lots, backing into approaching vehicle is the most prevalent.

5. Improper Turning

Drivers are turning from the wrong lanes and or failing to signal their intention to turn (turn signals).

No Lane Splitting in PA

Posted: 07/03/2010 in Uncategorized

There have been multiple search queries on our blog relating to lane splitting in PA. In a nutshell, it is not allowed. See the relevant statute below:

 § 3523.  Operating motorcycles on roadways laned for traffic.
        (a)  Right to use of lane.--All motorcycles are entitled to
     full use of a lane and no motor vehicle shall be driven in such
     a manner as to deprive any motorcycle of the full use of a lane.
        (b)  Overtaking and passing.--The operator of a motorcycle
     shall not overtake and pass in the same lane occupied by the
     vehicle being overtaken.
        (c)  Operation between lanes or vehicles.--No person shall
     operate a motorcycle between lanes of traffic or between
     adjacent lines or rows of vehicles.
        (d)  Limitation on operating abreast.--Motorcycles shall not
     be operated more than two abreast in a single lane.
        (e)  Limited access highways.--No motorized pedalcycle shall
     be operated on any limited access highway.
        (f)  Exception for police officers.--Subsections (b) and (c)
     do not apply to police officers in the performance of their
     official duties.

I started a new page entitled Letters to Brandon (found at the links on the top of the blog).

These letters are written from the perspective of a new young rider receiving instruction and advice from a distant relative. They were inspired by a true situation where a son/daughter purchased a new motorcycle (probably under parental protest) and the parents are rightfully, very concerned.

This made me think about a time in the near future when my own sons and daughters may want to be like Dad (scary thought) and ride motorcycles. What will I tell them and how can I give them the best advice?

This is an attempt to make the principles taught in this blog very personable and hopefully a different way to communicate the same truths.

If anyone finds themselves in a similar situation, direct them to the letters for advice and instruction. This is in no way to replace formal training. In fact, if your son or daughter is going to ride a motorcycle; insist they take a rider’s course, like the MSF (Motorcycle Safety Foundation) course.

Well I guess it finally had to happen. After 8 years of providing police escorts for group rides we had our first mishap.

I guess technically our record is still unblemished because the incident did not occur at a police control point, but nonetheless we felt crappy about it.

We were on the final leg of our ride and encountered a detour (road closed ahead). The detour road was narrower with a relatively sharp right into a sharp left with about 150 feet in between. There was a soft shoulder along the right fog line.

The bikes were starting to come closer together slowing down for the detour.

My partner was riding along my left offset behind me near the center-line. I was along the fog line (near side). My turn was a little wide coming off of the second curve into a straight-way and I hit the soft shoulder. I kept the throttle constant and did not brake and rode ride through it, only kicking up a little dust.

At about the group mid-point other riders did not fare so well. One rider rode into the soft shoulder and dumped the bike, another rider, immediately behind him, ran into the first biker.

No one was seriously hurt and the bikes were ride-able.

Safety Points

  1. A pre-ride should always be conducted as close to the event date as possible to identify any new hazards or traffic patterns.
  2. A safety brief should be conducted explaining reactionary gaps, arm signals and contingency plans.
  3. Always allow no less than a 2 second following distance, even in formation, with the bike ahead in your line.
  4. It is important to have complete use of the lane for changing lines when an evasive maneuver is needed.
  5. Upon the completion of an evasive swerve, return to your position in formation immediately to maintain a 2 second synchronization throughout that line.
  6. When the road narrows and it is impractical to keep a staggered formation, the lead rider should signal for a single line formation.
  7. Lead riders should do a pre-ride of the intended route before the event, noting special problems and hazards and if necessary, make changes.
  8. Remember to adjust your speed accordingly, keeping in mind less experienced riders at varying skill levels will be behind you maybe trying to keep up.
  9. If you have a police escort, keep in mind their job is to secure traffic points, not to lead a ride.

Several Points about the Above Ride

The aforementioned ride had no pre-rides from the organizers. In fact, they had no one leading the ride and relied police to lead. This resulted in several problems:

  1. A pre-ride by ride leaders would have identified the detour and any peculiar hazards. A reduction in speed and single line formation might have prevented the above mishap.
  2. Police cannot effectively lead a ride, that is entirely a different job. The motor officers primary job is to control traffic points at intersections, making it safer and keeping the group together. Motor officers must remain flexible through out route to deal with special problems at any point. Their job is not to direct the group but to function outside of the dynamics of the group; they do not ride with the group per se but around the group, leap frogging, bump-n-go’s, scouting, etc.

Two buddies were riding last night, it was dark with streetlights, straight road, approaching a High School entrance/exit.

The first rider, using the right side of the lane (near side) was about 10 feet ahead of his buddy, who was riding offset on the left side of the lane.

The first rider noticed an SUV pulling out from the entrance/exit of the High School on the right. He said he cracked the throttle several times in an attempt to get the drivers attention.

The first rider (despite loosing distance) was able to slow down enough to swerve to the right, behind the SUV and miss crashing. His buddy, ran directly into the driver’s side door.

There is no doubt the SUV is at fault for failing to yield the right-of-way to a vehicle approaching so close as to constitute a hazard.

Could the second rider have avoided this collision by simply braking?

The amplification of sound through your exhaust is never the preferred method of attempting to get someones attention who is about to violate your right-of-way. A long steady horn blast and braking is your best course of action if you have detected the hazard in time.

Too much valuable distance can be lost in engaging the clutch to crack the throttle for the amplification of sound without accelerating into the vehicle.

If you are traveling at 40 mph and your “cracking” your throttle for a couple of seconds, than you lost about 120 feet of evasive braking to avoid a collision.

The distance needed to stop at 40 mph is only 71 feet, plenty of distance to come to a complete stop even if the vehicle encroaches your path of travel.

We suspect in  this collision the rider that contacted the vehicle had no reaction because he was following his buddy and did not detect the hazard at all. His buddy’s position in front and to his right may have obstructed his view.

When riding with others, you should allow enough following distance and time to react, at minimum 2 seconds. Utilize the entire width of the lane to gain better position in response to possible hazards. While multiple riders will typically ride in formation, staggered usually, this does not mean you cannot move within your lane for advantage.

What are the available evasive moves to avoid a collision?

  1. Slow down
  2. Speed up
  3. Turn left
  4. Turn right

Simple right? So what’s the problem (rhetorical)?

Guidelines (discussed throughout this blog, often):

You must be attentive.

You must recognize hazards.

You must position your bike within your lane for advantage.

You must know how to threshold brake for maximum braking efficiency (use your front brakes).

You must know how to steer (countersteer) to avoid obstacles.

You must ride your own ride, even when riding with others.

NOTE: The driver of the SUV was also a licensed motorcyclist. He was not able to accurately judge the closing speed of the bikes in the conditions described above. Should he have known better? You decide.

Unlicensed, Unskilled and Out of Luck

Posted: 05/27/2010 in Crash
Tags:

Yesterday, I had the rare occasion of actually witnessing a crash involving a motorcycle. Not just the crash but the whole sequence of events.

A rider turned in front of me from a side road. What I noticed about him immediately was the slow awkward riding with a swaying from left to right. Possible impairment, no turns out he was smoking a cigarette. The road was straight leading into a sharp right hand curve (the type you can take at 30 mph but its posted with a warning speed of 15 mph).

He kept his approach line close to the double yellow line, doing about 2o mph, did not lean very much and then things got interesting. An approaching car was straddling the centerline but remained in his lane while he closed in on the rider. The vehicle passed the rider without incident but the rider reacted by turning the handles to the right, probably wanted to get out-of-the-way and move over to the left. But what happens when you steer the handle bars to the right? The bike goes left. The rider drove into the opposing lane and got clipped by the next vehicle coming around the curve.

The bike was about broad side when impact occurred. The right front corner of the pick-up contacted the bike several inches from the riders’ right leg (left of center of mass). After impact the bike rotated clockwise and went down across the lane into a clear grassy area.

Turns out (pun intended) the rider was on a borrowed motorcycle (2005 HD Deuce) and had a drivers’ license but no motorcycle endorsement.

This collision fell into some of the typical Hurt findings:

  1. Short trip associated with errands
  2. Accident is likely to happen in a very short time close to the trip origin
  3. Lack of attention to the driving task
  4. The ability to counter-steer and swerve was essentially absent
  5. Without motorcycle license

Tips for the riders and owners in this collision:

  1. Loaning your bike is like co-signing a loan, better not to do it.
  2. Owner’s can be cited for permitting violation of title (vehicle code) if they allow unlicensded riders to ride their bike (I did not know is not going to cut it, it is the owners’s responsibility to ensure riders are properly licensed)
  3. Owners, be aware of your insurance coverage before loaning your bike. Liability insurance, as in this case, only covers other people and property in the event your at fault it does not cover you or your property.
  4. What affect will an unlicensed driver have on your insurance claim?
  5. Riders need to be attentive ALWAYS, smoking cigarettes while riding is NOT recommended. You have only about 2 seconds to execute an avoidance maneuver, don’t eat up valuable time futzing around
  6. If you don’t know about counter steering then find out about it before your next ride, the rider in this collision could have been seriously hurt because he was unskilled in steering a motorcycle at speed
  7. Select an approach line to a curve that does not expose you to on-c0ming traffic. Vehicles coming from the opposite direction have a tendency to straddle the centerline, especially on sharp curves, to a closer position to the right or nearside to offset this

If you choose to ride unlicensed and unskilled, time is working against you. Sooner or later, your luck will run out, when it does, hopefully you will survive it. It is better to remove luck from the equation. Don’t put your friends in a position to have to pay for your mistakes.

I guess it’s time to stir things up a bit. This applies to all drivers in Pennsylvania. Check your states prevailing laws to see if there is a conflict in your state.

Chapter 2 – Signals, Signs and Pavement Markings PA Driverʼs Manual says, “A double, solid yellow centerline shows the center of a two-way road. Even if it is not marked with a NO PASSING sign, passing by traffic traveling in either direction is not allowed on roads marked in this manner.”

“Not allowed…”, well then there most be a law (regulatory) to make passing on double yellow line illegal right?

Well, no, there is not. Title 75 (PA Vehicle Code) does not make passing on a double yellow centerline enforceable. There are limitations, which we will show but it cannot be said that passing on a double yellow is “not allowed.”

Let’s be careful here, make no mistake, if you are in a collision and you are on the wrong side of the road you will be at fault. However, I believe it is profitable to know what the law says for several reasons:

  1. Minimize unfounded complaints of illegal passing being processed through 911 centers.
  2. Preventing a lawful pass only induces other problematic driving (high speed variances, following too closely, carelessness)
  3. On the flip side, safer passing could occur if we talk about when it is safe to do so instead of stating, unreasonably, passing is never allowed on a solid double yellow.

Let’s take the time to learn what is actually prohibited by the Vehicle Code, and use the parameters to promote safer driving by safer passing.

High speed variance percentages is actually more problematic than speed limits per se. High variances will induce violations like  tailgating, higher risk driving, poor sight selections for unlawful passing. We will discuss speed variances in more detail in another post.

So what does the law say for PA? Below are the relevant sections of Title 75 relating to overtaking with my comments in red:

§ 3303. Overtaking vehicle on the left.

(a) General rule.–The following rules shall govern the overtaking and passing of vehicles proceeding in the same direction, subject to the limitations, exceptions and special rules stated in this chapter: (1) The driver of a vehicle overtaking another vehicle proceeding in the same direction shall pass to the left of the other vehicle at a safe distance and shall stay to the left of the other vehicle until safely clear of the overtaken vehicle. [Nothing here about double yellow lines]

(2) Except when overtaking and passing on the right is permitted, the driver of an overtaken vehicle shall not increase the speed of the vehicle until completely passed by the overtaking vehicle and shall give way to the right in favor of the overtaking vehicle on suitable signal.

(b) Suitable signal defined.–Suitable signal for purposes of subsection (a)(2) shall be as follows: (1) At all times when head lamps are required to be lighted according to section 4302 (relating to the period for requiring lighted lamps), an audible signal or the intermittent flashing of low and high beams except that the use of high beams shall not be permitted when a vehicle is approaching from the opposite direction within 500 feet. (2) At all other times, an audible signal.

What are the limitations, exceptions and special rules?

§ 3305. Limitations on overtaking on the left. No vehicle shall be driven to the left side of the center or  marked center line of the roadway in overtaking and passing  another vehicle proceeding in the same direction unless the left  side is clearly visible and is free of oncoming traffic for a  sufficient distance ahead to permit the overtaking and passing  to be completely made without interfering with the operation of  any vehicle approaching from the opposite direction or any  vehicle overtaken. In every event the overtaking vehicle must  return to an authorized lane of travel as soon as practicable  and, in the event the passing movement involves the use of a  lane authorized for vehicles approaching from the opposite  direction, before coming within 200 feet of any approaching  vehicle. [Please noet that if passing on a double yellow was illegal, it would be stated here. However, we find no such restriction. Instead, the standard of clearly visible and  free of oncoming traffic is established. ]

§ 3306. Limitations on driving on left side of roadway. (a) General rule.–No vehicle shall be driven on the left side of the roadway under any of the following conditions: (1) When approaching or upon the crest of a grade or a curve in the highway where the driver’s view is obstructed within such distance as to create a hazard in the event another vehicle might approach from the opposite direction. (2) When approaching within 100 feet of or traversing any intersection or railroad grade crossing, unless otherwise indicated by official traffic-control devices. (3) When the view is obstructed upon approaching within 100 feet of any bridge, viaduct or tunnel. [Please note again that there is no stipulation here making double yellow lines a limitation in and of themselves. It denotes several dangerous conditions when you are not permitted to pass.]

What about no passing zones? Why would you need signs to mark no passing zones if all you need are solid double yellow lines?

The fact of the matter is in order to enforce no passing, with the exception of the limitations listed above, you must properly post the segment of roadway were no passing is prohibited. Please note in the section below that no passing zones must be properly posted. No where in this section does it stipulate that passing on double yellow lines is illegal.

§ 3307. No-passing zones. (a) Establishment and marking.–The department and local authorities may determine those portions of any highway under their respective jurisdictions where overtaking and passing or driving on the left side of the roadway would be especially hazardous and shall by appropriate signs or markings on the roadway indicate the beginning and end of such zones and when the signs or markings are in place and clearly visible to an ordinarily observant person every driver of a vehicle shall obey the directions of the signs or markings. Signs shall be placed to indicate the beginning and end of each no-passing zone (emphasis mine). [Nothing here about double yellow lines and note there must be signs in place to mark beginning and end. If there is only a sign marking the beginning and not the end, then would the department and local authorities be in compliance of this restriction? If not then how can this be enforceable?]

(b) Compliance by drivers.Where signs and markings are in place (emphasis added) to define a no-passing zone as set forth in subsection (a), no driver shall at any time drive on the left side of the roadway within the no-passing zone or on the left side of any pavement striping designed to mark a no-passing zone throughout its length.

In conclusion, if the segment of roadway is not posted no passing and it is clear and free from oncoming traffic and it is not approaching upon a crest of a grade or a curve in the roadway where the driver’s view is obstructed and it is not within 100 feet of an intersection or railroad crossing or if you view is obstructed within 100 feet of any bridge, viaduct or tunnel, you are good to go.

Pass with care and within the guidelines discussed and the roadways will be a little safer for all of us.

Update 1/14/11:

If it is the intent of PA legislators to forbid passing on double yellow lines then they need to stipulate that by amending the existing vehicle code statutes relating to overtaking. The language of the law does not support that passing on double yellow is “not allowable”. It clearly is (within the limitations  above).


On Cornering

Posted: 04/24/2010 in Cornering
Tags:

It may be helpful for some riders to gain a cursory understanding, without getting too technical, to understand what is involved in cornering or turning. While this post is not meant to be an exhaustive treatment on the subject, here are few points to mull over.

Your ability to turn is going to involve three things:

  1. Your own ability (how far can you lean or the correct lean angle for the speed you are traveling?)
  2. Available road friction
  3. Tire adhesion

Turning requires a balance of forces to keep the bike upright. Understanding how these forces work may help you make better decisions.

The Technical (Leaning for balance)

While a motorcycle is turning it undergoes uniform circular motion. Just bear with us for a second, a centripetal force is acting whenever rotational motion occurs, since such a force is required to change the direction of the motorcycle from a straight line. Friction between your tires and the road provides the centripetal force needed rounding a curve.

The centripetal force that must be exerted to maintain uniform circular motion increases with increasing mass and speed, with the force being more sensitive to any change in speed. If your curve radius increases the required centripetal force reduces.

In turning at high-speed the rider must lean the bike to maintain balance. Leaning the bike effectively changes the center of gravity. Too much lean and parts may drag on the road (muffler, foot-pegs, crash-bars) causing the rider to fall and the motorcycle will slide on its side (then I get to come out and figure how fast you were going and if you were at the correct lean angle for the radius of the curve).

There must be sufficient road friction available in leaning a bike. In other words, the road surface must be able to support the tire forces of the bike when turning.

Excessive lean will cause a centrifugal force across the road surface while the road surface can no longer counter with an equal frictional force, causing the tires to break traction and slide out. In other words, when centrifugal force exceeds the lateral friction the potential for a slide-out greatly increases.

In a curve, all forces act through the combined center of gravity (rider, passenger, cargo). The force arising from lateral acceleration is balanced by the frictional forces developed between the tire and road surface.

Rider Ability

Inexperienced riders are sometimes afraid to lean enough to compensate or balance forces for higher speeds for fear of falling over. In fact, many inexperienced riders to not lean more the 25 degrees. The result being the motorcycle traveling off the roadway or into the opposing lane. Keep in mind inexperienced passengers may cause similar problems.

Sometimes the rider will favor one side over the other and lean farther on one side than another. In order to maintain lane placement in a curve a sufficient lean must be achieved. Lane placement is very important since the most you are going to have is about 10-12 feet (typical lane width). This why it is important not to fixate on any specific target like a BFT (big freaking tree). Fixation will cause a deviation from your line.

As the rider develops and becomes more familiar with the machine, leaning ability will increase. If you are carrying a passenger, an adjustment in speed and lean angle must be made. A passenger who is not familiar with the motorcycle will not lean with the rider or leans in the opposite direction of a turn. If this happens, it has a negative effect on the riders lean and steering, canceling them causing the motorcycle to go straight.

The Road

There must be sufficient road friction available in a leaning motorcycle to stay upright, if there is not, and you are exceeding the available friction, you will go down. The road surface must be able to support the tire forces.

Similar to a car, there is a maximum speed at which a motorcycle can negotiate a curve. In reconstructing motorcycle crashes, if we know the maximum lean angle of a motorcycle and the radius of a curve, the maximum speed can be calculated at which a certain motorcycle can negotiate the curve.

Remember, after the fact investigators have all day long to collect data to do analysis, how much time do you have to make a decision about proper speed and lean angle?

Tire Adhesion

Your tires ability to use the available road friction is the other part of the cornering equation. There are a host of reasons or variables causing poor performance and instability, some of the biggies are:

  1. Correct Tire Matching – correct matching of front and rear tires are important for performance handling. A new front tire with a worn rear can cause instability. Mixing radials, or radials with bias tires can cause instability.
  2. Correct Tire Pressure – under-inflated tires will affect the preciseness of cornering, result in higher running temperature, irregular tire wear along the edges of your contact patch, fatigue cracking, over-stressing and eventual tire failure. Over-inflation will result in a harder ride and accelerated tire wear in the center of your contact patch.
  3. Wheel balance – it is essential tire and wheels be balanced, unbalanced tires/wheels can vibrate at certain speeds