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MOTORCYCLE SEASON KICKS INTO HIGH GEAR

Motorcycling can be an exhilarating experience. Yet it can also be a dangerous and all too often tragic one unless the riding task is taken seriously.

In 1990, motorcycles comprised about 2% of all registered vehicles. While the number of fatalities has declined over the past few years, motorcycle drivers and passengers still represent a disproportionate 6.6% of all fatalities.

Of all motorcycle drivers in fatal collisions, 57% were under the age of 25. In fatal collisions approximately 60% of the errors attributable to the motorcycle rider were excessive speed, or loss of control. Of the drivers in fatal collisions, 21% were not properly licensed for the vehicle.

Riding at night is even more dangerous than riding during the day. The majority of fatal accidents happen after dark. One of the major problems for motorcyclists at night is alcohol abuse. Drinking and driving is a problem for motorcyclists, whether they themselves have been drinking or if they are just trying to avoid being hit by drinking drivers. In 1985, alcohol was involved in more than two-thirds of the single-vehicle motorcycle fatalities in Ontario.

MOTORCYCLE VISIBILITY

Car and truck drivers involved in collisions with motorcycles often say that they didn't see the motorcycle soon enough to avoid the accident. Sometimes, they claim that they didn't see it at all. A motorcycle can be pretty hard to see. From ahead or behind, its outline is much smaller than a car's. Motorcycles that aren't seen are often hit.

At night, motorcyclists depend mostly on their lights to be seen. If riding on a dark road, the headlight will be very visible to a driver ahead. However, in traffic with other headlights behind, an opposing driver may not be able to pick a single headlight out of all the lights behind. This problem is especially bad when the roads are wet as the glare from lights reflects off the road surface.

One of the most common causes of motorcycle/car accidents is the car driver turning left in front of the motorcycle. The car driver either doesn't see the motorcycle of misjudges its speed. The motorcycle rider may not be completely innocent in this situation, fi the motorcycle is going faster than the driver would expect.

WEAVE & WOBBLE

Since a motorcycle is two-wheeled vehicle, it is not stable at rest. Motorcycles gain stability primarily from the gyroscopic action of the rotating wheels.

Due to their basic design, motorcycles are subject to two interesting types of instabilities called "weave" and "wobble". Both are high speed instabilities that rarely occur at speeds below 100 km/h.

Weave is a snake-like oscillation of the motorcycle around its centre of mass. It is usually confined to the rear end of the bike, having only a small effect on the steering end. The motorcycle literally weaves from side to side along the path of travel.

Wobble is a "fluttering", a rapid oscillation, of the front tire/handlebar assembly. We sometimes wee this motion in an unsupported caster on a shopping cart. When wobble sets in, the motion becomes so severe that the rider usually loses control and crashes. The only thing a motorcyclist can do in a wobble is to ride it out; firmly grip the handle bars, don't try to fight the wobble and gradually slow the motorcycle down without applying the brakes.

Weave and wobble can be caused by several factors. These include weight distribution, centre of aerodynamic pressure, loose steering-head or wheel bearings, wheel alignment, tire inflation, tire size, tire tread shape and wear and rider weight. Add-on accessory boxes, windshields or fairings can change both the weight distribution and the aerodynamics of the bike and thus contribute to weave/wobble.

GO SAFELY!

It should be remembered that a motorcycle is one of the smallest vehicles on the road and drivers and passengers are vulnerable in the event of an accident. To survive, a motorcyclist must ride defensively.

There is plenty of additional activity on the roads now that the fair weather is here; motorcycles, bicycles and pedestrians. Motorists should operate their vehicles with keen perception and prediction, obey the rules and go safely!

 
The information contained in this web site is intended for marketing purposes only. It is not all-inclusive, and does not fully describe the many and varied services that the company provides, nor does it completely describe the education, training, skills, or expertise of our staff.

 
 
 

Walters Forensic Engineering | 277 Wellington Street West, Suite 800 | Toronto, ON M5V 3H2
Information contact: engineering@waltersforensic.com