Apr 10, 2006

Slide rule

I read this in a magazine today, as answer to the question 'What is a highside?'. I'm quoting now:

'A high side occurs when a rider tries to accelerate too hard out of a turn, resulting in the rear-wheel spinning. This makes the rear step out of line and if the rider doesn't back off the power, it results in the rider low-siding the bike. But if the rider immediately goes off the throttle, it will make the rear tyre grip the road again suddenly, extending the suspension and flicking the bike violently enough to throw the rider off it. It is best to back off the throttle just a little bit, to get the bike back straight up again.'

I don't agree at all. A highside, to complete the picture, is the (deservedly) the most feared sort of single-bike crash, because the when the tyre grips again, it not only flicks the rider off, it usually follows him into the air, and then tries its violent best to land on him. If the thump of the landing isn't enough to break bones, the motorcycle usuall will.

Second, you don't solve a spinning and sliding rear end, tending towards a highside by 'backing off the throttle just a little bit.' Primarily because, that just a little bit, could be enough to have the motorcycle turn into the Incredible Hulk and prepare to put first in orbit, and then out of it. No, the solution to a highside lies in damping out the panic reaction – 'CLOSE THE THROTTLE!' and staying on the gas. And if possible, adding more fuel to the fire, while sliding backwards in the seat. Let me explain. At the end of the day, a motorcycle is a rear wheel drive vehicle. A sliding rear combines with the dropping revs to produce a forward weight transfer. That means, even less traction at the rear, intensifying the slide. Which is not what you want to do, right?

When you open the throttle further, and/or slide back in the seat, you attempt to bring more traction to the back wheel. It may not work all the time, but the results will always be far less violent than trying to 'back off the throttle a little bit.'

There's more. Suppose the throttle and subtle body re-position doesn't work. You still should not be coming off the throttle. Because that means a low side, which if you're wearing full kit, will leave you with either no injuries at all or minor road burns (unless you slide into a hard object - like a light pole, but you're not going that fast on the street, right?). All preferable to hospital food, traction and acres of plastered limbs. Those who want more information, including the physics of a highside please click here.

I also spoke to an ex-racer who I think is pretty fast almost everywhere, a natural talent. When he'd been racing RD350s, he'd have the rear sliding quite often. He found that opening the throttle would work ninety per cent of the time. It'd solve the problem and look heroic from the trackside. 5 per cent of the time, he would need to slide back as well. This would solve the problem, and look (and feel) very, very dramatic indeed. 5 per cent of the time, he'd low side, stop sliding, get up, pick up the bike and continue. I think that's a fair equation, what?

1 comment:

SamY said...

that was a nice one mate ... gud into in crisp