Chasis hieght/angle important?

Hi Guys, KZ 900, late model gsxr swingarm, 92 kawasaki 1100 front forks,(or should I use kawasaki 636 forks?).
How do I determine where to mount the top of the monoshock? I set the swingarm pivot point at 16 inches. Same as gsxr. Now the front end seems a little low. That would help handling right? The swingarm is a couple inches longer than stock. This would add stability? Does everything average out or am I asking for trouble? Thanks! Mike

Hi Mike,

These machines are usually designed by teams of engineers and then often only changing an existing frame a bit at a time.

Who Knows you may just build a new wonder bike or you may just end up a bunch of spare parts for other future projects.

I'd start from an existing known quantity and change one part at a time.

KZCSI

I believe that the key number for the swingarm is 10-13* swingarm droop. If you keep the same linake geometry as the Gsxr then the the mounts for the shock should fall close to where they need to be.

Also for the front end, the newer bikes' steering heads are lower, hence the shorter forks. You'll need to measure relative rake and compute the trail from that figure. Also remember the more jacked up the read end is the more the chain is going to touch the swingarm.

Later, Doug

i try and aim for having the bike sitting low and swingarm level with my 200 lb ass sitting on .mock up your frame and swingarm with wheels on it sitting about where you think it should be with suspension loaded ,if you know the compressed height of your shock make yourself an adjustable strut from a pice of all thread and a couple clevis's and use it as a guide of where to tack your shock mount .

plummen that is pretty smrt im going to use that[steal]idea on my next build.

dont thank me ,we're all in this together!:laugh:

As stated above, it takes teams of engineers to finalize a motorcycles geometry. For this reason, I would recommend trying to preserve the original geometry as much as possible unless you can tweak it later. Even a small change in something like the swingarm can cause a huge change in the motorcycle's attitude, and some changes can be downright dangerous (i.e. if you reduce the chainpull angle to the point where it gets close to the angle of momentum, when the bike is squatted on a turn it can oscillate between negative and positive chain pull - can you say "bucking bronco"?). If as you suggest, the rear end is higher than stock, you could make the bike quicker to turn in (or more skittish).