TOTW: Keep your wrist flat to avoid throttle problems
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?
Slight variations in how you position your wrists and arms can have a significant impact on your safety and comfort while riding. In particular, untrained riders have a tendency to “Cock their wrists,” riding with their wrists slightly bent, and the “Point” of their wrists higher than the lines of their forearms. This seemingly minor point can have serious side effects on your riding.
You have a problem with your wrist position if you experience any of the following symptoms:
- When you are accelerating, the bike sometimes feels like it is trying to run away with you, accelerating harder than you had in mind.
- If you have to brake hard, such as in an emergency situation, you sometimes find yourself stopped, with the clutch in, and the engine racing at high speed.
- You have trouble keeping a constant, smooth throttle while steering around corners.
- Your wrists and arms ache after relatively short journeys.
What are the causes?
If your bike sometimes feels like it is trying to run away while you are accelerating, you have your wrist bent, and higher than the line of your forearm. It’s best to visualise this problem while sitting on your bike, with the engine off. Hold the throttle with your right hand, and cock your wrist so that it’s quite high above the throttle. Now imagine what happens when you are accelerating. As the acceleration pushes you backward in your seat, the backward pressure will straighten your wrist slightly, which forces you to roll on more throttle, against your will. This additional acceleration pushes you back still further, forcing you to roll on even more throttle. The situation “feeds on itself” and can be quite frightening, especially for new riders.
This same incorrect wrist position causes the problem of a racing engine after a hard braking manoeuvre. Again, sit on your bike with the engine stopped. Hold the throttle with your right hand, with your wrist very high. Now, watch what happens if you quickly grab the front brake lever and squeeze.
Chances are, as you applied pressure with your fingers, your thumb rolled down the inside of the throttle grip, rolling it on while you were braking. You will end up stopped, with the brakes firmly applied, and with the “Crotch” of your thumb and forefinger firmly pressed against the throttle tube, holding it open. This throttle locking was a common problem experienced by students first learning emergency braking in our courses.
A similar analysis may explain why you have trouble maintaining smooth throttle settings while steering around corners. As you move the handlebars, you are unconsciously changing the angle of your cocked wrist, changing your throttle setting.
Finally, incorrect wrist position is often associated with another error: leaning forward and supporting your upper body weight on your wrists. This will give you sore wrists and sore arms very quickly.
By the way, the photos above have exaggerated the wrist bend to help you see the problem. But even a very slight bend, like this, can cause the problems we have been discussing.
The solution to all these problems is the same, and simple. Keep your wrists straight, in line with your forearm, not cocked. Also, keep your arm bent slightly at the elbow, so your forearm is roughly parallel with the ground. Small motions as the bike moves under you, and as you corner, should be absorbed into your relaxed elbows, not transmitted into your wrists. Don’t lean on your wrists to support your body weight. Instead, use your thigh and hip muscles to hold yourself up.
With your wrist flat, you cannot accidentally role on more throttle while accelerating. You will have to reach a little farther with your fingers to apply the front brakes, but you will be less likely to roll the throttle on with your thumb. If your hands are so small, or your bike so large, that you can’t reach your brake lever from a proper wrist position, check if your brake lever position is adjustable (many are). If it isn’t, talk to your service establishment. There are many ways to modify your front brake lever position, and this problem needs to be fixed.
Photos on this page show a bare hand so you can see the wrist position. Never ride a motorcycle without gloves.