TOTW: Drive over obstacles more smoothly by doing what doesn’t come naturally

The riding tips on these pages are my personal opinion about matters related to motorcycle riding. They are not the official position of any organization, and are for your consideration only. They are not hard and fast rules, they should not necessarily be applied in all circumstances, and they should not be applied without thinking. Always use your judgement and take all current safety factors into account while riding. You are responsible for your riding, not anyone else (especially me). These tips were originally published by a motorcycle riding course, called “Tip of the Week” (the reason for the TOTW in the titles).

What’s the problem?

Sometimes you have to drive over an unavoidable obstacle in your path. (A speed bump, which is designed to be unavoidable, is a perfect example.) You probably find this a jarring, unpleasant experience.

You feel an unpleasant thump as the bump is transmitted through your front wheel and into your arms and knees, and you probably wonder if the thump has damaged your wheel. You may feel a loss of steering control, especially if you didn’t hit the obstacle square-on.

Ordinarily, a bike’s front suspension is designed to smooth out bumps in the road. The problem with an obstacle like a speed bump is that you saw it coming and your natural reaction was probably to brake before you hit it.

Think about that. What happens when you apply the brakes? Your front forks compress, and the front end of the bike dives. With the front forks compressed they have less slack left to absorb a bump — under hard braking, with the forks fully compressed, they have effectively become solid metal bars. The force of the bump is efficiently transmitted into the bike and your body.

Solution

You need to learn to manage the condition of your front suspension. In this case, we’re going to de-compress the front forks before hitting the obstacle, by “blipping” the throttle at the right time.

Try this.

First, find a safe street or parking lot, and ride at a moderate constant speed. Have a friend observe your front forks while you brake. He’ll tell you the front forks compress.

Now have your friend observe while you “blip” the throttle. Blipping means quickly snapping the throttle open a quarter-turn or so, then back to where it was. Quickly — the blip should last less than a half a second. You get a “brmmmm!” engine note that quickly rises in pitch then returns to normal. Your friend will tell you that the front forks de-compressed for the moment after the blip. That makes sense — it’s the opposite of braking. Extra caution: keep the blip small and brief until you get a feel for how much fork decompression you get — too much and you may lift your front wheel right off the ground, which makes your bike very hard to control.

This is very important. We are not talking about accelerating. The blip should last a fraction of a second, and you should travel only a metre or two at the higher engine speed. We don’t mean you hear “bwaaaaaaaAAAH” and accelerate down the road.

Now find a stable obstacle in a safe place. A 10 cm. speed bump in a quiet parking lot is ideal. Approach it at a moderate speed (20 Km/h or so). Brake to slow down if necessary, but finish braking several metres before you reach the obstacle. Then, just before you hit the bump, blip the throttle.

Again, blip quickly. You want to accelerate for just a fraction of a second, and time this so your forks decompress just before you hit the bump.

The decompressed forks will absorb the blow much more effectively than the compressed forks that resulted from braking, and you’ll feel much more comfortable and in control.

Later, try combining this with another technique: slightly reduce the weight on your seat by pressing your feet down on your foot pegs, again, just before you hit the bump. With the blip and weight reduction done properly, you will barely feel the bump.


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