Category: Riding Safety

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Coping With a Skid

A skid – that’s when your heart leaps
up to your throat because your
tires have lost traction!
You might hit a patch of sand on a
mountain curve, or a puddle of oil as
you’re slowing for a stoplight. It’s a
frightening experience on a
motorcycle, but you can handle it.
In a highway-speed, sand-in-the corner
skid, steer slightly in the
direction of the skid. (If you’re leaned
to the left and skidding to the right,
turn those handlebars a bit towards the
right.) Chances are you will clear the
patch of sand, the tires will grip the
pavement again, the bike will stand up,
and you’ll continue on your way.
Should you hit a slippery bit while
you’re braking for a stop sign, and one
or both wheels lock up, you want to
get those wheels rolling right away.
Release the brakes for an instant, then
reapply a little more gently. You want
those tires to have traction.
At higher speeds, when traction is
good and the rear wheel skids when
braking hard, do not release the rear
brake.
If your back end is skidding sideways
because the tire is on a slick spot
and simply spinning, ease off on the
throttle. A spinning wheel provides no
more control than a locked wheel.
You might be in one of those two mile-
per-hour parking lot scenarios, a
mild, low-speed skid when your front
wheel starts to go out from under you.
A foot on the ground may keep the
bike upright and the rubber side down.
This is not an easy thing to do, and
should only be done if all else fails.
Michael Theodore
National Road Captain

 

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State Watch Motorcycle Legation

 

I am going to be posting something new in the rumblings newsletter each month which has to do with motorcycle laws and bills. I will be posting a few states every month. If your like me a motorcyclist you want to know what your state or other states are doing to help with motorcycle safety and motorcycle riders.

Did you know that some state’s have motorcycle -only checkpoints?
Hawaii
Bill HB 727 is in legalization that would authorize the state department of transportation to allow motorcycles and motor scooters the use of shoulder lanes when congested.
Massachusetts
Bill H 1917 flied by state Rep .Timothy Whelan (R-Brewster), would allow motorcyclist to proceed through red lights after stopping and “exercising due care,” if the signal is controlled by a vehicle detection device that is not triggered by the motorcycle.
Massachusetts
Motorcyclist are attempting to get the state’s mandatory helmet law repealed again this year, with S.1923 would do just that. The bill was introduced bt state Sen. Anne Gobi There was about 175 riders showed up at the state capital to lobby in favor of this bill.
Michigan
The state Senate voted to raise registration and training fees for motorcyclist. The annual registration fee goes from $23 to $25. Initial endorsement fees go from $13.50 to $16,and renewals from $5 to $7. The additional registration fee revenue will go to the motorcycle safety education program, while some of the endorsement fee revenue will fund a new program promoting motorcycle awareness.
Oregon
The Governor signed into law H.B 2598, which extends the offense of vehicular assault to include contact with a motorcycle operator or motorcycle passenger.
Pennsylvania
The state’s House Consumer Affairs Committee approved a measure that would cover motorcycles under Pennsylvania’s Automobile Lemon Law. H.B. 74, introduced by state Rep Pam Snyder would include motorcycles in the law’s definition of a “new motor vehicle” and require manufacturers to correct any defects that impairs the use, value or safety of the vehicle and occurs within one year following delivery, within the first 12,000 miles of use or during the term of the warranty, whichever comes first.
Pennsylvania
The state House passed H.B.831 which gives motorcycles processions the same rights as funeral processions. State Rep Mark Keller, the bill’s sponsor, said, “As an avid motorcycle rider who has taken part in many large group rides, said his legislation would bring group riders into compliance with the state vehicle code and make them safer for both the participants and other motorists.” If passed by the state Senate and signed into law, the bill would allow motorcycle processions to proceed through red lights and stop signs, control and direct traffic and bypass motorcycle-only checkpoints.
Minnesota
S.F.2405 would permit motorcyclists to split lanes on public roads within the state if the rider does not exceed 40 mph and travels no more than 15 mph faster than surrounding traffic.The bill was referred to the Transportation Finance and Policy committee.
Louisiana
Lawmakers have passed H.B.161, which provides exceptions to Louisiana’s anti-masking law, and sent the bill to the governor for signing. The bill exempts motorcyclist from the state law that prohibits the wearing of masks in public, except on holidays, such as Halloween. Motorcyclist in Louisiana said some overly zealous law enforcement officers have been using the anti-mask law to stop and cite bikers who were using face shields on their helmets.
Washington
A state law that bans the use of hand-held devices while driving a car took effect on July 23. Under the new law, anyone older than 18 may no longer hold a phone while driving,except to call 911 for emergencies or to activate or deactivate a call or select GPS navigation. Those younger than 18 already fell under those restrictions.
Nebraska
Nebraska  officials deployed eight trucks featuring safety messaging around the state as part of a 10-week program to promote motorcycle safety. The campaign by Nebraska Highway Safety Council was promoted by a spate of fatal motorcycle crashes this past summer. The state Department of Transportation, law enforcement agencies and motorcycle safety groups help with the campaign.
Michael Theodore
National Road Captain

 

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Ridin’ in the Rain

 

Many, if not most, of us consider riding in the rain a necessary inconvenience when we’re caught out in it while going from point A to point B. The experience is frequently made more burdensome because of: inadequate riding gear, reduced vision of scenery and road hazards, loss of traction, increased navigational challenges, and fogged glasses and face shield—just to name a few. Often we discover too late that we forgot to pack defogger, rain mittens, Rain-X, or some other item critical to reducing the discomfort and increased risk of riding in the rain.

It’s my contention, however, that riding in the rain is often less pleasant than it really has to be, partially because we avoid doing it unless forced to ride in the wet. But like most of motorcycling’s other acquired skills, practice almost always leads to a better riding experience. In that vein, here are my top ten tips for improving your rain proficiency and, yes, even enjoyment:

Expect Rain: Even if the sun is out, and there’s not a cloud in the sky before leaving home, expect the possibility of rain during any ride that lasts more than a couple of hours. That means riders should almost always pack rain gear. And, by the way, most textile riding gear that says it’s rain resistant, or even waterproof, usually isn’t in a long, soaking rainfall. My rain gear is 100% waterproof and if I’m riding all day long in the rain 6 or more hours it the rain does find a way to creep in.

Trust Your Tires: One of the biggest phobias of inexperienced riders, once pavement becomes wet, is that their tires will rapidly lose traction. The soft rubber composition of motorcycle tires (especially compared to car tires) means that most of them retain about 80-percent of their traction on wet pavement. The presence of oil, antifreeze, or any one of a number of other chemical substances on rain-slick roads, however, can significantly compromise traction. If wet asphalt appears to have a reflective sheen, these chemicals may be present. One way to evaluate a road surface is to lightly drag the sole of one riding boot to determine if pavement is actually slippery. I must add that I forgot this my own practice what you preach stuff this summer. And  I laid my bike down one summer on fresh paved Wet asphalt. While riding in a storm. Came in contact with not one but two oil slicks.
Avoid Plastic Strips on Pavement: Pedestrian crossings and some other road markings are actually white plastic strips adhered to the concrete. These strips become slippery when wet. The same is true for metal road surface coverings, tar snakes, wooden planks at railroad crossings, and other similar road materials not made of asphalt or concrete. If these hazards cannot be avoided, then ride over them at a right angle, at moderate speed, with the bike perpendicular to the road surface.
Treat Your Face Shield: Recently On a face shield treated with Rain-X (which works better on glass than it does on plastic) or some other chemical that increases surface slipperiness, wind will largely clear the raindrops from view. It’s also not a bad idea to treat your shield before beginning any ride. If your shield fogs up, don’t open it completely, because that will enable rain to deposit on the inside, which is hard to clear without stopping and removing the helmet to do so. Make sure all helmet vents are open and only crack the shield slightly to increase airflow and exhaust condensation. There is anti fog spray for the inside of your face shield to stop fogging also.
Inspect Rain Gear Integrity: Over time rain gear can loose its ability to repel water. I learned this lesson once, the hard way, when my out dated rain gear began leaking during a daylong ride in heavy rain. The combination of riding wet in the wind caused me to lose body heat, become chilled, and then sick enough that I couldn’t continue riding the next day. Now I replace  worn rain gear and buy suits with heavier gauge material.
Be Visible: I will never understand why some companies make black rain gear, particularly the jacket. It’s hard enough to see riders in rainy, low light conditions without making them virtually invisible to human sight. If your rain gear top isn’t especially colorful or visible, wear a hi-viz vest over it. Because most other vehicles will have their lights turned on in the rain, reflectors also will improve other motorist’s ability to see and avoid you.
Slow Down: Although a relatively small amount of traction is lost on clean wet pavement, it still makes sense to ride more carefully in the rain by avoiding: (1) excessive speed; (2) steep lean angles; (3) close proximity to other vehicles and (4) aggressive stopping maneuvers.
Don’t Push Your Luck: It’s one thing to ride in rain, but quite another to ride into a thunderstorm or even a heavy downpour. If I listen to myself preach I would of not had that accident this summer. Because your riding risk factors are already heightened in rainy conditions, know when to get off the road and take shelter. Remember, your rubber tires won’t provide any protection in the event of a lightening strike and there’s nothing between you and flying debris picked up by high winds. Common sense should tell you when it’s time to “fold ’em.”
Practice: Here’s a radical idea: go riding in the rain, even when you don’t have to! As is true with most other motorcycle riding skills, practice improves ability, confidence, and enjoyment of the experience. The same is true for riding in the rain. Practice effective rain riding techniques close to home so they will be second nature when you need them on a road trip.
Learn to Enjoy the Experience: The rhythmic pitter-patter of raindrops, while ensconced in a warm dry cocoon, can be both enjoyable and relaxing. It only can be so, though, after mastering tips one through nine above. I’ve heard of some motorcyclists who enjoy rain riding so much, they actually look forward to rainy days in the saddle. Ok OK This is Me I like rain riding yes I’m a Nut a Buckeye nut LOL. I would ride to work almost everyday rain or shine.

Long story short, a rainy day doesn’t mean that your two-wheeled adventure has to stop being fun.

Michael Theodore

National Road Captain

 

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Human Vision

Drivers often say, “I didn’t see it” — after hitting a motorcycle!

I bring this up because one day last month I was at a stop sign, and while stopped I looked left then right, and then left then right. As I thought “all is clear” I then attempted  to move forward — only to realize a smaller motorcycle was in my path. I clearly did not see him at all. No, I did not hit him, but I know I gave him a huge scare, which brings me to this: Looking in the direction of something does not mean that we see it!

In general, we only see what we expect to see, or what we’ve trained ourselves to see. Our brain is wired to filter out much of what our eyes receive, focusing on specific items based on each individual’s experience and judgment, taking into account the relevance of the input to the task at hand, its location, perceived threat level, and any movement, and then prioritizing takes place even if important information is directly in front of us. Also, we have visual clarity in only a  three-degree cone in the center of our vision (“central vision”).

Some people believe they get better information from their peripheral vision then they actually do. To have a useful “big picture,” our central vision must be consciously directed to capture the important details. In other words, instead of our eyes passively transmitting images to our brain, our brain needs to direct our eyes to scan the environment, like a searchlight. Successful scanning strategies involve moving attention far-and-near, and side-to-side, to identify relevant factors, especially those that have little or no movement of their own.

The more effectively we gather information, the better we can make decisions and take appropriate action. This continuous process is called “S.E.E.” — Search, Evaluate, Execute. If searching identifies a hazard, and evaluation determines the hazard that should be avoided and suggests various ways to avoid it, the next step is executing an action. If you are lax with your eye movement, the visual field can “stagnate,” and less conspicuous items, such as motorcycles coming straight at you in an inter section, are rendered virtually invisible. Eye movement is critical, because, as hard as it is to notice and act on important clues in the central vision, imagine if those clues are outside that three-degree cone!

Just as hazardous as not focusing on the right thing in your visual environment is focusing on a single, wrong thing. Good riders keep their eyes moving, so they are able to detect and evaluate factors several seconds ahead and to the sides. This includes giving extra attention to known problem areas, such as intersections (including driveways) and blind corners, and periodically checking your mirrors to construct a “big picture” of the environment. I am always moving my head and eyes — scanning and checking my mirrors. Are you? Just ask my wife, and she will tell you: my head is always moving. Just remember your motorcycle may not be categorized as a ‘threat’ by the CAR/SUV driver’s brain, so your image is filtered out.

Michael Theodore
National Road Captain

 

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NO JERKS ALLOWED

Did My Title get your attention
Membership in this club has its privileges. It is called the Smooth Riding Club.
So how does one become part of the smooth riding club? What are the requirements for membership? Simple just be committed to continual improvements and safer riding. In this club we don’t need people who are ignorant and inconsiderate of others, but what I really mean here is that members in this club are consistently smooth and precise. No jerks, no clunks, no head banging, no abrupt and jarring moves. How can one get the keys to the smooth riding clubhouse? Well I will let you in on a few club secrets.
READ THE ROAD AHEAD Getting your eyes up and looking farther ahead means you can eliminate the constant steering corrections that are common when riders focus just a few yards ahead of the front fender. Looking farther ahead also helps you anticipate activity up ahead, allowing you to eliminate surprises and respond smoothly and calmly to developing circumstances.
MAINTAIN A LIGHT TOUCH. The smoothest riders keep a very light touch on the handlebars and guide the bike with subtle inputs instead of steering the bike with forceful, tight-fisted stabs and tense,stiff arms. Lightly and tenderly movements is key.
MAKE BRAKING ULTRA-SMOOTH. Most riders could benefit by improving their braking transitions. Skilled riders recognize the need to allow smooth weight transfer from the rear wheel to the front during braking, and then back to the rear again as throttle is reapplied. To avoid bouncing the suspension like a pogo stick and accomplish a smooth transition, a minimum of 3-4 seconds should be allotted for braking, allowing sufficient time for smooth brake application and release (longer,if greater braking effort is applied). Think of braking like squeezing someone’s hand. Don’t grab. Instead, use a progressive squeeze and a polite release.
EXECUTE SEAMLESS UPSHIFTS. What is the trick for smooth up shifting? Three overlapping steps and regular practice. Start by pre loading the shift lever with your boot (you are wearing boots, right?). Apply just enough pressure to suggest the shift, not enough to cause an actual shift to occur without disengaging the clutch. Secondly, when your ready to make the shift, gently squeeze the clutch lever just far enough to be in the friction zone. ( You do know what is the friction zone is?).
It’s not all the way to the handlebar. The pre load shift lever will slip effortlessly into the higher gear. Thirdly, reestablish smooth and steady throttle as you ease the clutch back out of the friction zone for a silky smooth and silent up shift.
MAKE SILENT DOWNSHIFTS. The mark of a truly proficient rider is how he or she executes ultra- smooth down shifts with no clunks, jerks and no”turtle kisses” ( This is when riders and passenger bump helmets). In addition to pre loading the shift lever as described in up shifting, the trick is to match engine rpm with the gear you’ll be shifting to. How? Some riders blip the throttle as they squeeze the clutch lever. I prefer to hold the throttle steady in place of rolling off the throttle during the shift. I then squeeze the clutch lever only enough to allow the shift lever to snick into the lower gear (don’t squeeze the lever all the way to the handlebar). With practice, every down shift will be marked only by a change in engine sound, not by clunks and jerks. By dedicating efforts to work on these key techniques, you will not only see a marked improvement in your ability to ride more smoothly and expertly, you’ll be among the distinguished membership of the smooth riding club, And that’s not a bad club to be in. After all, there are no jerks allowed.
Keep The Contact Patch Between The Lines
Michael Theodore
National Road Captain

 

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Touring Tip Be A Safer Night Rider

Be A Safer Night Rider
A riders risk factors increase once the sun goes down. To avoid an accident, it’s important to see and be seen.
Here are some tips for avoiding road hazards at night.
Keep a clear view: In low light conditions, wearing sunglasses or having a tinted shield on your helmet further diminishes your already restricted ability to spot road hazards.
Check Headlight Adjustment: Changing load conditions on a motorcycle can alter where the bike’s headlight falls on the road. Make sure the headlight on your loaded bike is adjusted properly before it gets dark.
Upgrade Your Headlight Bulb: If your bike’s headlight puts out a relatively weak beam, upgrade it with a more powerful bulb. Always carry an extra one and know how to install it.
Add Auxiliary Lights: There’s a reason why most bikes set up for round -the-clock Iron Butt events have additional lights mounted on them: They are riding long hours, often at high speeds, in the dark, and must have more illumination than is provided by just a headlight.
Use your High Beam: Whenever there’s no oncoming traffic, shift to your high beam. This will help you spot hazards farther down the road and peripherally.
Don’t Deer Me: If your route leads you through wooded or rural areas, assume that deer will be present and ride accordingly: slow down, ride in the left one third of your lane (when there is no on coming traffic), keep fingers resting on the front brake handle and clutch, and be alert to potential hazards materializing suddenly from the roadside.
I personally like to follow a Car/SUV/Truck when riding in a deer zone. I let them be my blocker incase of hazards.
Protect Your Night Vision: If you stare at the lights of an oncoming vehicle, your pupils will constrict and dramatically reduce your night vision. Focus instead on the white line on the shoulder until the vehicle passes.
Position Your Bike Defensively:  If you’re following a four – wheeled vehicle at night, Your ability to spot and react to road hazards is reduced. If you are riding in the middle of your lane and the vehicle ahead straddles something in the road, you’ll be lucky to spot it in time to take evasive action. However, if you follow that vehicles left rear tail light, you’ll know if there’s a road hazard in your path, because the vehicle will likely swerve to miss it.
Be Reflective: Aside from just your reflectors that come with your bike, it’s good idea to add reflective material.
Add Auxiliary Lights:  In addition to helping riders see better, auxiliary lights also make it easier for them to be spotted by others, including pedestrians, who other wise may step into your path.
Avoid Blind Spots: Staying out of a car or truck’s blind spots is critical at night. Position your bike so you and your lights are clearly visible in their mirrors of other vehicles. Don’t use your high beam though while behind a vehicle.
Signal Your Intent: As a rider you should always use your turn signals for turns and switching lanes.
Add More Red More Brake Lights: It is always good to add another brake light more LED to the back of your bike. And another good tip when at a stop is to keep your brake on to have your brake light lit up. I always have my foot on my brake pedal when I come to a complete stop. Just added safety here.
Do a Once-Over: It doesn’t do much good to have headlights,tail lights,turn signals, and auxiliary lights if they’re not all working. It is always a good Idea to check them.
I leave you this one last note. Night riding is much more dangerous but can be enjoyed when you slow it all down and Light it all up. I enjoy riding at night. Once again keep the contact patch between the lines.
Michael Theodore
National Road Captain

 

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60,000 Mile Motorcycle Tires Would you buy them?

The other day I was discussing tires with a non-motorcyclist friend of mine. He is a very smart man that is in management who is well schooled in physics and logic. Imagine my surprise when I learned that not only were a few tire facts not understood by him, but that most of my motorcyclist friends, whose lives depend in no small part on their knowledge of our sport, have the same blinders on.

When I told my  friend that motorcycles can almost always stop more quickly than cars, I did not get the typical agreement based on the popular misconception that this is true because cars are heavier than motorcycles. Instead, he challenged that fact based on the ‘increasing popularity of ABS system on cars.’

  • Stopping distance is not determined by weight! You will recall that Galileo (I originally said ‘Sir Isaac Newton’ in error) crushed the popularly held belief that heavier objects fall faster than lighter ones. Falling is an acceleration. Braking is simply a negative acceleration.
  • ABS was not designed to enable you to stop more quickly. (Goggle  Anti-lock Braking Systems (ABS).)

As we got on with our discussion of tires he happened to mention that he had just purchased a set of new tires for his car and that he expected to get about 60,000 miles from them before they wore out. This seemed to please him very much. I’m afraid I may have caused him to have second thoughts on the matter as our conversation continued.

I told him that I had a set of ‘high mileage’ (by motorcycle standards) touring tires on my motorcycle and that I would be happy to get anything in excess of 20,000 miles from them. He was amazed to learn that I paid nearly as much for my rear tire alone as he spent for all four of his car tires, particularly since I would have had to replace them three times before he replaced his once.

It must have sounded defensive on my part when I told my friend that if the manufacturer of my motorcycle tires was to announce a new tire with an expected life of 60,000 miles they would have trouble selling them.

I explained that the reason a motorcycle can stop faster than a car is that its tires provide better traction than automobile tires. Our traction is better because the rubber compounds our tires are made of are softer and thus ‘stickier’. Beyond their price in dollar terms, better traction tires cost mileage – they wear out faster than harder tires. [Obviously, stopping is a function of your brakes. With the assumption that your vehicle was designed with brakes that are more than sufficient to lock (stop your wheels from turning), regardless of speed, then the stopping of your vehicle must be limited by available traction, not brakes.]

(It is a curiosity to me that many motorcyclists brag about the mileage their tires provide – actively seeking to buy higher mileage tires without a thought to relative traction provided. I suppose that they believe the higher mileage is provided without traction cost – but is it?)

However, given a choice between buying tires that lasted three times as long or those that allowed faster stopping, it would be a no-brainier for most motorcyclists. If a motorcycle tire could be made that provided 60,000 miles of life, by virtue of being made of harder rubber compounds, the manufacturer could not give them away.

Well that concept got the attention of my friend! Can’t you just imagine the thoughts running through his head: 
Maybe.

The problem is that there is no way for a consumer to know what level of traction one tire has as compared to another. There is no indication on the tire sidewall, for example, that lists its traction, and there does not appear to be standards available to the consuming public that facilitates comparisons. It is entirely possible, though unlikely, that a rubber compound can be developed that provides longer life without sacrificing traction.

But there are other reasons that most motorcyclists should consider before buying a tire with a long wear life expectancy. For example, about every other tire that I have had to replace was the result of tire damage rather than normal wear and tear. (three nails in three tires just last year alone, severe sidewall cracking along with similar cracking in the tread grooves, cupping, etc.) If you push your tire all the way to the end of it life you are putting your self at risk with loss of traction.

Maybe the discussion above explains why no manufacturer has announced a 60,000 mile motorcycle tire – yet. I wouldn’t buy one if they did. Would you!
Michael Theodore
National Road Captain

 

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Weight Transfer What is it, why does it happen, and why should you care?

When you change speed (accelerate or decelerate) the weight of your motorcycle (including you) shifts in such a way as to put more or less load on your tires. You do not have to weigh the load on your tires to know this with certainty because you can see it happen by observing your front-end ‘dive’ when you brake.


Traction is proportional to the weight carried by your tires. Thus, when you brake your front tire gains traction while the rear one loses it. Clearly losing too much traction is dangerous since the result is that your tire will slide.

Despite what you may think, weight transfer can be controlled beyond simply adjusting your acceleration and braking rates. That is, how fast you change speeds is not the only thing that determines weight transfer. Surely you would be interested in minimizing the odds of losing traction during a panic stop? Read on… 

Braking Transfers
Ignoring wind resistance, essentially all the forces that try to slow you down when you apply your brakes are at ground level. That is, at the contact patches of your tires. On the other hand, the inertia of your bike works not at ground level, but directly through its center of gravity (CG.) Since the CG is higher than ground level the resulting net force translates into a torque. In other words, braking does not simply shift weight forward, it tries to shift it down in the front and up in the rear.

The higher the CG is, the greater the torque. (If the CG was at ground level the torque would be zero.) On the other hand, the longer your wheelbase is, the lesser the torque. This is just another way of saying that the amount of weight transfer resulting from a change in speed is a function of the ratio of the height of the CG to the length of the wheelbase.

Gravity is acceleration. At ground level gravity tries to make you fall with acceleration at the rate of about 32.2 feet per second per second (henceforth  fps/sec.) This acceleration is called ‘1 g.’

‘Weight’ is a force. Weight is simply how hard a mass is trying to fall to the center of the earth because of gravity. Like inertia, gravity works directly through the CG of an object.

When we brake we apply force which we will simply call a braking force. Braking is nothing more than a negative acceleration. Thus, when the total braking force is such that your bike’s forward speed is being reduced at the rate of approximately 32.1 fps/sec, you are decelerating at the rate of 1 g. That is, your braking force then equals the weight of the motorcycle (including the rider). If your motorcycle weighs 1,000 pounds, then braking at 1 g means you are applying 1,000 pounds of braking force.

You can calculate the amount of weight transfer involved in any stop knowing only the braking force being used and the ratio of CG height to wheelbase length. For example, if the total braking force is 1,000 pounds, your CG is 20 inches off the ground, and your wheelbase is 63.4 inches long: 

Wt.Transfer = Braking Force times CG ratio

Wt.Transfer = 1000 lbs. * 20/63.4

Wt.Transfer = 1000 lbs. * .3155

Wt.Transfer = 315.5 lbs. 

[We are here discounting entirely the effects caused by tire distortion and suspension compression. Not because these are not important, but because they are of secondary importance to an understanding of these principals.]

Now, just because the bike weighs 1,000 pounds and is sitting on two wheels does not mean that at rest there are 500 pounds on each wheel. Here again we need to know something about the bike’s CG. Only if the CG is exactly in the middle of the bike (between contact patches) will the weight be evenly distributed. If the CG is closer to the front wheel than the rear one, for example, then there will be more weight on the front tire than on the rear when the bike is at rest (not moving). Further, unless there is an upward or downward movement of the bike, the sum of the weight carried by the front and rear tires must equal the total weight of the motorcycle and rider.

Let us assume that at rest the weight is evenly distributed. Then we now know that while braking at 1g, because of weight transfer, there will be 815.5 lbs. (500 + 315.5) on the front tire and only 184.5 lbs. (500 – 315.5) on the rear tire. Because traction is a function of weight carried by a tire it is clear that there is not a lot of traction left on the rear tire at this time.

Let us look very carefully at what this weight transfer example is showing us. You have heard that you have about 70% of your stopping power in the front brake. This example shows that we have applied 1,000 lbs. of braking power to the tires of the bike. If it was ALL the result of using only the front brake, then we have wasted what traction is still available to us from the rear tire and, worse, we have locked our front tire and started a skid! This, because virtually all standard tires lose their ‘sticktion’ (stick/friction) when confronted with more than about 1.1g of braking force. With 815.5 lbs. on the front tire it could with reasonable confidence handle a braking force of 897 lbs. (1.1 * 815.5), yet we applied 1,000 lbs. to it. At least in this case our front brakes could deliver nearly 90% of our stopping power, not just 70% – but not 100%, either.

Now let us look at what would happen if the CG happened to be 30 inches high rather than 20: 

Wt.Transfer = Braking Force times CG ratio

Wt.Transfer = 1000 lbs. * 30/63.4

Wt.Transfer = 1000 lbs. * .4732

Wt.Transfer = 473.2 lbs. 

The front tire would have 973.2 lbs. of weight on it and the rear would have only 26.8 lbs. This is close to doing a ‘stoppie’!!!

What we are beginning to see is that if the CG gets to a height of 1/2 of the length of the wheelbase we can expect to do a ‘stoppie’ if we use 1g of braking force. Further, if we use even the slightest amount of rear brake in such a configuration when we are slowing at the rate of 1g, we can expect to lock the rear wheel.

One more example – we will attempt a 1.1g stop with this ‘higher’ bike: 

Wt.Transfer = Braking Force times CG ratio

Wt.Transfer = 1100 lbs. * 30/63.4

Wt.Transfer = 1100 lbs. * .4732

Wt.Transfer = 520.5 lbs. 

At this point we have transferred MORE than the entire weight which had been on the rear wheel – we have left the rear wheel with NEGATIVE 20.5 lbs. on it. I.e., our rear wheel has been lifted off the ground!!!!

Notice, please, that the CG does NOT remain at a constant height during aggressive braking. If we use exclusively front brake, then the front-end will dive and the rear-end will lift. This could result in the CG remaining at the same height, but more likely it will get higher. We have already seen that a higher CG means more weight transfer. Further, as the front-end dives the result of the compression of the front shocks is a shortening of the wheelbase of the bike. This, like raising the CG, results in a higher CG to wheelbase ratio, and therefore more weight transfer. [As an aside, if your bike has an anti-dive feature (TRAC, for example) then MORE weight transfer occurs to the front wheel than without it. This, because the CG is held higher. In other words, anti-dive INCREASES the odds of sliding your rear tire!]

If only the rear brake is used there will be a weight transfer to the front tire which will tend to compress the shocks. Additionally, however, use of the rear brake tends to LOWER the rear-end of your motorcycle and lengthens its wheelbase, (the swing arm become more level). The net effect is to lower the CG of the bike. This offsets neatly the fact that the compressing front-end shortens the wheelbase at the same time. However, since there is a weight transfer, the rear-end gets lighter while braking which quickly limits how much braking power you can apply before you skid that tire. In other words, you must use the front brake for maximum stopping power.

From the above discussion I think you can now see that the use of your rear brake along with the front brake leads to less weight transfer than if you use only the front brake, and why the use of both at the same time always results in maximum stopping power.

When a rider mounts his motorcycle he both raises the CG and moves it towards the rear. The heavier the rider, the more significant these changes to the CG are. We already know that as the CG rises it causes more weight transfer during speed changes. This raising of the CG is far more significant than is its shift towards the rear. (This, because the height of the CG is small compared to the length of the wheelbase.)

What this adds up to is that the heavier the driver of the motorcycle, the easier it is for braking to cause a breakaway of the rear-end. Is there anything that can be done to mitigate this potentially deadly problem? You bet! In a panic stop the driver should bend from the hip and elbows and lean forward! This will cause the CG to lower and move forward. A lower CG is more significant than its slight movement forward. In summary, there will be less weight transfer with him leaning forward than if he was sitting straight up in the saddle, there will be less compression of the front shocks, and less shortening of the wheelbase. I.e., less likelihood of losing rear-end traction.

Anything else? Yep. Always pack your saddlebags with heavy items towards the bottom. Every pound below the CG lowers it, every pound above it raises it. 

Accelerating Transfers – Straight Line
This article has so far focused only on weight transfer associated with braking. It should be obvious that exactly the same phenomenon happens when you accelerate – the amount of weight transferred is determined by your rate of acceleration and the CG ratio (height of CG divided by length of wheelbase.) Though you may not believe that you have an ‘anti-dive’ component for your rear wheel like you may in the front, you do. The rear wheel does not push the frame forward directly. It pushes its ‘swing arm’ forward. Since the swing arm pivots on the frame aft of your CG, and since that pivot is almost invariably higher than where the swing arm attaches to the rear wheel, any accelerating force applied through the rear wheel tries to lift the frame of the motorcycle. I.e., rather than calling this an ‘anti-dive’, think of it as an ‘anti-squat’. This keeps the CG higher than it would be otherwise and the result is that there is greater weight transfer to the rear tire (and correspondingly higher traction results.)

Accelerating Transfers – In A Curve
Constant Speed
And what about weight transfers when you are in a curve? You have heard the terms ‘over-steer’ and ‘under-steer’ before, I’m sure. Over-steer means that when you are in a curve your rear wheel is more likely than the front one to lose traction (i.e., your sliding bike will end up pointing towards the inside of the curve.) while under-steer is the opposite. Weight transfer to the rear tire from acceleration leads to over-steer (greater slip angle on rear tire) while braking in a curve, because of weight transfer to the front, leads to under-steer (greater slip angle on front tire.) Both are deadly concerns if you push tire loads to their limits!! (On the other hand, if you have a choice you would almost certainly want a little over-steer rather than under-steer because a brief slide of the rear tire is easier to correct than a similarly brief slide of the front tire.)

It would be a deadly mistake to try to use the kind of weight transfer analysis we have discussed so far in an effort to learn how much acceleration to use while in a curve to equalize tire loads! (I now assume that you have read and understand the article entitled ‘Delta V’.) The weight transfer calculations we have been looking at so far deal with consequences of longitudinal acceleration. In a curve you are also subject, even if maintaining constant speed, to centripetal acceleration.

Unlike longitudinal acceleration (changing your speed), which changes your tire loading in a simple proportion to the CG ratio, centripetal acceleration increases tire load in proportion to the SQUARE of your change in speed. The formula to determine these forces is: 

Force = Mass times Velocity squared divided by Radius
F = M*V^2/R
You can assume that most street tires will lose traction when they are subjected to about 1.1 g of force. So how do you tell whether you are close to 1.1 g when in a turn? Simple. If your effective lean angle is 45 degrees, you are experiencing 1 g of centripetal force. And, from the formula above you see that the force is extremely sensitive to velocity. This means that a very minor increase in speed could easily push you past the 1.1 g limit.

What you should understand from this is that using acceleration (speed change) to balance tire loads while in a curve is foolish. (In general, however, you will want some (minor!!!) acceleration in a curve as this tends to increase the slip angle of the rear tire which increases traction, and because you want your rear-end suspension modestly loaded to enhance control.)

Now you know why you want to be sure the load distribution on your bike is set properly BEFORE you hit the road. 

Accelerating Transfers – In A Curve
Exiting The Curve
While a modestly increasing speed makes great sense while you are riding through most of a curve, it is understood that some people find great pleasure in rolling-on their throttle as they exit those curves.

Just a little thought, based on all that we have talked about so far, should now convince you that you must be conservative in this practice while you are leaned over hard, and that you need to be BOTH widening the curve and standing the bike taller as you do it.
In the case of the front tire, acceleration merely reduces loading because of weight transfer. Thus, traction is diminishing in proportion to that acceleration (i.e., traction is a function of the types of material that are being pressed together and the force pressing them together – since the load is diminishing due to weight transfer, so is traction.)

The effect of acceleration on the rear tire is quite different, however. You would correctly assume that weight transfer resulting from acceleration would increase traction on the rear tire. It does, during modest acceleration. But acceleration (increasing speed) is accomplished using the rear tire only. That is, there is no longitudinal acceleration affecting the traction of the front tire, just the rear one. 

Longitudinal acceleration and lateral acceleration are vectored, which means the resulting acceleration force is the square root of the sum of the squares of those forces. (In other words, more than either of them, but not as much as both.) As the rate of acceleration increases it quickly overwhelms the effect of increasing load on the tire (which increases traction) and begins to consume that traction faster than it is being added. 
 If you increase speed or decrease the radius of your turn, your lean angle will get larger. When your lean angle gets to 45 degrees, the lines will start at 1.0 and even a slight acceleration will push the lines over 1.1 – which means you will soon be exploring the joys of road rash.
Sorry my charts would not upload for some reason.
In summary, there are a few obvious reasons to care about weight transfer:

  • Traction is directly proportional to the amount of weight carried by a tire – managing weight transfer is managing traction.
  • Misloading your motorcycle can result in substantial handling problems – particularly in a curve.
  • In order to manage weight transfer intelligently you need to have a good idea of where the center of gravity of your bike is and what happens to it when you add a passenger or luggage.
  • Traction will probably be lost if tire load exceeds about 1.1 g. If you are in a curve and are leaning at 45 degrees, you already have 1.0 g tire loads. Enough is enough.
  • Stopping with your elbows locked guarantees more weight transfer and a higher center of gravity – both undesirable from a control point of view.
  • Rolling-OFF your throttle (or braking) if you are ‘hot’ in a curve is almost certainly more dangerous than simply leaning farther into the curve – because weight transfer will unload the rear-end which reduces rear tire traction.
  • Under-steer and Over-steer both yield slides when load limits are reached – balancing the weight reduces the risk.
  • And who said you would never use math once you graduate from school.
          Michael Theodore
          National Road Captain

 

 

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May Is Motorcycle Awareness Month

May Is Motorcycle Awareness Month

With the beginning of Motorcycle Awareness Month on May 1, the American Motorcyclist Association is issuing a special appeal to motorists to be aware of their driving environment, check mirrors and blind spots before changing lanes and, especially, to watch for motorcyclists.

“The warmer weather in May brings out the riders who have been unable to ride all winter, so it presents an excellent opportunity for us to educate the non-riding public about the safety issues that affect motorcyclists every time we roll out of our driveways or onto a trail,” said Rob Dingman, AMA president and CEO. “The AMA is monitoring more than 1,124 state and federal bills that would affect motorcycling safety or motorcyclists’ rights, including many that deal with rider safety.”

Among the top awareness issues in 2015 are distracted driving and the need for motorcyclist and driver training.

Sean Hutson, AMA government affairs manager for on-highway issues, said state legislatures are considering more than 150 bills that deal with distracted driving. Those bills range from prohibitions on minors using personal electronic devices to bans on the use of electronic devices by any driver.

Rather than solely seeking bans on specific forms of behavior, though, the AMA advocates legislation that includes enhanced penalty options to be determined by the courts in cases where distracted driving results in a crash.

In addition, the AMA supports training programs for motorcyclists — including advanced skills courses – and more thorough education for motorists. A new law in Michigan, for example, requires motorcycle- and bicycle-awareness and safety instruction in all of the state’s courses for new drivers.

Drivers can avoid crashes with motorcyclists by taking extra care and looking twice to spot motorcycles in traffic — especially at intersections — respecting the motorcyclists’ space on the road and by not following too closely.

Motorcycle Awareness Month, launched by the AMA in the early 1980s and adopted by many state motorcycle-rights organizations, government entities and AMA-sanctioned clubs, is observed each May.  Ride Safe and be aware of everything around you while you ride.

Michael Theodore

National Road Captain

 

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Are You Riding Slower Than Traffic

Are you riding at a much slower pace than other road users, what’s is the best thing to do when faster traffic builds up behind you.
Speed is differential, whether you are riding faster or slower than the traffic flow, even if you are within the speed limit, this can be a hazardous situation. It can inhibit smooth traffic flow, it can make merging and changing lanes more difficult for all motorists and increase the chance of road rage.
If you consistently ride more slowly than other road users, you should first consider your routes carefully. You should avoid major highways and though fares if less traveled or lower speed routes are available.
If you must share the road with much faster traffic, Use the right lane when on the highways and check your mirrors more frequently.
However do not let the traffic behind you distract you from important factors ahead of you. If there is only one lane in your direction, periodically pull off to the side of the road (when it is safe and legal) or into a parking area to allow the vehicles clustered behind you to pass.
If you are traveling a lot slower than others, Encourage vehicles to pass you while you are riding with in marked passing zones by moving over to the far right side of your lane and give the vehicles behind you a clearly communicated hand signal. This should defuse the chance of any road rage.
Keep it in between the lines.
Michael Theodore
National Road Captain