Delta front wheel geometry

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I've been reading a lot on several sites and came upon an interesting vid link on bentrider. Mike Burrows is obviously a well respected designer/builder and he talks about the optimum head angle geometry and why we don't see it on bikes. I'd be interested to hear if anyone has used the upright steering tube he says is optimal?

John
Oops forgot to include the link-
 
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I have not watched it , however he is probably quoting from Tony Foales who did lots of real world testing including building motor bikes with variable trail and rake.

His work culminated in a renowned book Motorcycle Handling and Chassis Design: The Art and Science free PDF download if I have got the link right ?
If not look it up it is easy to find.

Paul
 
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Thanks Paul I'll do that just out of interest. I've no intention of giving it a try unless someone here can vouch for the better handling in practice.
Mike Burrows is apparently designer of the lotus team bikes if that means anything. In the vid he says he built a bike with adjustable geometry to test it out and found a vertical head tube with slight caster gave the best handling. He says BMW built a motorbike using the same layout and it was good at 100mph. Says the reason it's not used is because a rider could not reach the handlebars!
Vid is only a couple of minutes long and he has many similar shorts on all aspects of bike design/build.

John
 
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I would suggest that if that research was correct then every motoGP racing team would use it, where the bikes are all one-off prototypes, all components are made to work as designed and reaching the bars would be designed in. That none of them do tells me the research was almost certainly flawed. Working on a delta is another matter as I doubt much work has been done in that area.
 
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Well Paul/Darren Foales book is hard going but I waded through the chapter on rake and trail and also the appendix where he explains the trials he did with the BMW with adjustable geometry.
Won't pretend for a second that I understood it all (or even much of it) but it does seem that a much steeper head angle including vertical does bring definite benefits in handling. Lighter, more responsive and more stable steering! Only drawback he says was a judder when braking but this was due to lack of stiffness in the forks unit of the test bike.
A lot of his remarks were re the bike when leaning into and out of corners and quite a bit of the discussion covered this part of riding which obviously doesn't strictly apply to trikes but the smoothness, and improved low speed steering probably does?

He says a steeper head angle is starting to be used more as time goes on and competition teams discover the benefits? I'm not sure what to make of it all. I haven't got the experience to know if I build a trike with vertical head tube whether it's an improvement or not but I may well give it a try on build 2 or 3??????
 
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Whilst changing the head tube angle is easy , changing the rake of a fork to get the desired trail is not.
I doubt the 2 wheeler benefits transfer to a trike as you say.

Paul
 
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