Shorter Forks: Thoughts on replacing KZ750 H fork tubes with KZ750E

BUMP -- i DIDN'T GET ANY RESPONSE ON THIS POST, SO I HAVE BUMPED IT UP. ANYBODY???

On my current cafe racer/street fighter/hot rod project bike (KZ750H LTD) the steering head angle is raked greater than on the KZ750E STD model. Because of this, Kawasaki installed longer fork tubes on the H, all designed to give it that semi-chopper look that was popular back in 1980. I am thinking about installing a set of fork tubes from the KZ750E model into the KZ750H triple clamps (yes, the tube diameter and the distance between tubes is the saem on both). This means I will still have the greater rake angle, but with shorter forks, thus lowering the front of the bike. (I haven't measured how much this will lower the front -- that will come sometime this weekend if I get the time.)

For those that know something about bike steering geometry, what will this do to the handling of the bike? If I understand some articles about this correctly, shortening the front tubes will make the steering more responsive (the term I read was "more flickable"). That is the direction I want to go, so that the handling is set up more for doing some twisties in the Berkekley hills, rather than cruising over the Bay Bridge.

Is this a dumb thing to do? Will the result be unsafe? Besides looking out for clearance when the shorter forks are fully compressed, is there anything else I should be on the lookout for when trying this out? Should I make a corresponding drop in the rear suspension? (I would rather not, since I like having the full range of swing arm travel, the greater lean angle clearance, and I am tall enough that I do not need to lower the seat height.

Oh great KZrider Oracles in the Sky, I seek Enlightenment.

Post edited by: apeman, at: 2006/06/17 19:55

BUMP!

I raised the back of my bike approx 1 1/2" giving the same effect as deraking it thus reducing trail. Same effect would be had by shortening the forks. My bike feels much lighter, more responsive and is still stable. That's my bike, with me riding (I'm used to quicker handling Brit bikes). I would suggest experimenting by sliding your stanchions up through the triple clamps 'til you get the feel you want before swapping the stanchions. Just don't sacrifice stability for quick handling. A steering damper is also a good idea.

RE-BUMP! Anybody??

I have a similar situation/question... if you notice, the triple trees on 750H have less forward offset than those of, say a 650. This shortens trail. To counteract that, kawasaki placed the axle "forward" of the center of the forks, "leading" style. I'd like more room for bars & different tank on my 750, so I'd like to run a completely different front end, trees & all, not just forks. Measuring my 650, it appears the 750 would have the same, or close to the same trail with a 650 front swap. I'd rather like a 1000 police front, to get the wider, shorter wheel than stock, but I'm afraid to whack the handling.

Sorry, no answers, just more questions!

As mentioned, try sliding the forks up in the trees, should have basically the same effect as using shorter fork tubes.

apeman wrote:

RE-BUMP! Anybody??

...thought I answered your question

Post edited by: Fossil, at: 2006/06/20 22:34

what is a bolt on shorter fork for the 750h? anything else beside the 750e mentioned above?

Youll need to check your exhaust clearance. Or maybe just be careful going over speed bumps. What if you change the yolks(triple tree) as well? then you might get the quicker steering without losing too much height.
Good luck with it.

bike has good clearance, i have my H forks slide up in the tree right now about 1.5in. still think the front is too high. ive been looking on ebay for used forks, been asking for the lenghts. the spectre forks look like they would be good.

not looking to change the tree at all, just want an easy fork swap option that is shorter

bump

it looks like the 750ltd forks are longer. is there another fork that is shorter from say a 750 e or 650 ??? anyone know these lengths ?

You could install shorter spacers inside the forks. Or cut the springs.