Rear suspension lay out

Does anyone have a book or info on rear suspension layout?
I have a 76 kz900, with a 95 zx9 front end and a 02 zrx12 rear end. the rear shocks are too long to achieve a level riding bike.
Is the swing arms rear axle supposed to be in line with the pivot axle and drive sprocket centers at rest?
what would the optimum shock angle be? Is it advantageous to mount the lower shock mount as far away from the rear axle as possible?

i say they look best when theyre about level with pivot when loaded

tony foale has a book out on chassis design.

timebomb33 wrote:

tony foale has a book out on chassis design.

ah forget tony,go for the looks! :woohoo:

anyone have Tony Foale's book?

im no engineer but i would think having it as close to centerline as possible would be best since that is what youre trying to control and i would think that is the point where the most torque is being appied to the swingarm trying to basically fold it over.i would also try to keep in mind the arc that the swingarm pivots in and try to keep the shocks in position where they can compress and rebound instead of trying to bend themselves.

That makes good sense.
I do believe that a straight line between the 3 points would be best with the rider on the bike. I would really like to find out more about the best position for the shock.
I have read that there is an optimum lean angle. It will make the spring compression the most progressive. On either side of that angle it can be positive negative or even both.
Also, the shock mounts position, will have an influence on the amount of leverage applied. As 1 (top , or bottom) is moved in it will create more leverage .
I need to learn more about this so i can set it up right and buy the appropriate length shock.

here is the link to tony's steering geometry calculator.it is freeware,hth.
www.tonyfoale.com/

leon holmes

Thanks Leon.
the rake doesn’t seem to matter that much. i have had the rear end up and the bike at a level stance. this changed the rake from 22.5* to 26*. the bike handles fine either way.
i prefer it at a level stance though. when the back end is high it is not as comfy to ride. it puts weight on my wrists, and makes me slide towards the tank. so i would like to lower the rear with shorter shocks. i just thought it would be good to figure out the best setup geometry, for the rear shocks, before i make any purchases.
so i need more info on the rear end geometry.

ahsa.

leon holmes

531blackbanshee wrote:

ahsa.

leon holmes

Sory i'm slow. "ahsa" ??:side:

ahsa=i see senior.haha!
i have asked the members of the motorcycle chassis design e-mail list if they could help us with your problem.if they come back with any help i will let you know.

leon holmes