# The Naked Scientists Forum

### Author Topic: Feedback: How does leaning a motorbike affect direction of turn?  (Read 881 times)

#### thedoc

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##### Feedback: How does leaning a motorbike affect direction of turn?
« on: 28/07/2015 03:50:01 »
Mike Duff  asked the Naked Scientists:

Re the bike going right when right bar pushed forward. After 30 odd years in a bicycle saddle (and thousands of kms) I can only conclude the following:

At slow speeds the bike will go where you point it as there is no real forward momentum. At higher speeds the following will happen. As you push the right bar forward and the bike starts going to the left, the momentum caused by your body weight will continue going in a forward direction. Now unless you lean into the corner (and you keep the bike upright as the caller suggested) the forward body motion will pull the bike over to the right as it begins to turn left. As it leans over to the right it will begin to turn to the right. Obviously the faster one is going the more pronounced it will be. Hence the reason why we lean into corners to counter the forward projection of the body.

Hope this offers a possible solution and makes some sense!!Have a good weekend

Regards Mike

What do you think?
« Last Edit: 28/07/2015 03:50:01 by _system »

#### Colin2B

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##### Re: Feedback: How does leaning a motorbike affect direction of turn?
« Reply #1 on: 28/07/2015 09:58:34 »
What you say is true, but only part of a very complex process.
If you take an ordinary push bike, hold it by the saddle and lean it to one side, you will notice the front wheel turns in the same direction. As a biker you will know that this is due to the front wheel geometry, rake angle etc.
There are other effects, researchers have discovered that in initiating the turn we start by unconsciously, and momentarily, turning a micro amount away from the turn - called counter steering.
Fascinating subject and lots of factors involved.

#### chris

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• The Naked Scientist
##### Re: Feedback: How does leaning a motorbike affect direction of turn?
« Reply #2 on: 28/07/2015 10:34:25 »
It sounds totally unintuitive doesn't it!

#### The Naked Scientists Forum

##### Re: Feedback: How does leaning a motorbike affect direction of turn?
« Reply #2 on: 28/07/2015 10:34:25 »