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When you think about it all your bike control skills can be reduced to just two areas:
- changes of speed
- changes of direction
By changes of speed we refer to the activities of braking and accelerating. Use of the throttle and brakes shifts the load front and rear in such a way as to put more or less load on your tyres.
Changing direction involves steering and leaning the bike, allowing us to corner and throws up more complicated lateral forces.
Ask yourself, when is a motorcycle most stable? Clearly either of these activities reduce stability so the answer must be when it is upright and travelling in a straight line at a constant speed. The more
extreme your changes of speed or direction, the more you compromise stability.
Ask yourself, when do you have most options open to you? If you think about it, if you are braking, you compromise your ability to steer, and if you are cornering, you compromise your ability to brake.
Thus the answer must be that if we want to keep the bike stable and options open - ie the ability to brake OR steer - you want to keep the bike upright as much as possible.
This has implications in the way we deal with corners. A traditional line through, for instance, a left hand bend uses the maximum radius by starting wide on the right, clipping the apex mid-turn and
exiting wide on the right. However a moment's thought will show that the bike is leaned for a long time and at a relatively large lean angle throughout the corner. There is also a danger that you may not
be able to see the exit clearly when you start to peel in - it is easy to misjudge and turn in too early. This is a common cause of "running out of road" errors on the exit to the turn.
The most stable line according to the Stability Rule thus has a MINIMUM radius on the turn to keep the bike upright as long as possible. When you turn into any corner, the safest line is to brake whilst
upright, put the power on and keep the bike at a steady speed or gently accelerating on a wide line (ie on the left of the road near the kerb on a right turn, near the centre line on a left turn), until
you can actually see the exit (ie the straight bit of road where you can open it up). When and only when you see the exit, use countersteering to turn towards it. Get the bike steered nice and quickly,
and you can pick it up out of the lean nice and quickly too. Then AND ONLY THEN do you apply hard acceleration, when you are pointing in the right direction.
This technique is sometimes called "point and squirt" but it works. Andy Ibbott used it in an MCN tip earlier this year. Basically this deep entry, point and squirt technique has a lot of
advantages over the "classic" line.
For a start it is safer - you see more of the corner before you start to turn, allowing you to line up the bike more accurately. You can see hazards like parked vehicles, a double apex or road surface
problems like diesel spills sooner, so you have more time to react. It keeps you away from extremes of position and gives you a margin for error.
Secondly it clearly agrees with the stability rule. With the deep in, point and squirt line, because the bike is longer on the brakes, it is upright later. Because you are longer on the brakes, you don't
need to brake so hard. Because the speed is lower in the middle of the turn the bike has less lean angle, therefore more grip and a margin for error to tighten the turn if necessary. Because the bike is
pointing at the exit sooner, the bike is also upright sooner, so you can get on the power sooner, without fear of running wide in the turn. Less lean angle is always good! Keeping the time and distance
when the bike is learnt over as short as possible is also good.
Thirdly it's usually faster. In the space that the traditional line needs to corner on that maximum radius line, you can be slowing upright and accelerating upright again, even though your mid corner
speed is actually lower.
The only trade offs are:
- you have to make is a quick steer at the turn in point, replacing your lazy steer on the classic line - this can take some getting used to, and can if used to extremes upset the bike's stability
itself
- you might not get your knee down because the "point and squirt" technique gets you round the corner with less lean angle!
Copyright © 2000 Kevin Williams
Last Page update Thursday, March 20, 2008
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