'96-'97 ZX9R swap to '77 Kz1000 LTD Frame

If you decide to look into a custom top yoke, Les at PDM does beautiful work and is a long time member here. See icon at bottom of the page.

TexasKZ wrote: If you decide to look into a custom top yoke, Les at PDM does beautiful work and is a long time member here. See icon at bottom of the page.

Thanks TexasKz. I’m already working with another machinists on the triples but will be buying the rear sets from Les.

The ones you have shown here are by Roy Martin in the uk. He machined mine and I asked him for a drop in mine to help level my frame out with the usd forks, are you getting hime to machine yours?

Theses are the ones he did for me.

kzstreetfighter71 wrote: The ones you have shown here are by Roy Martin in the uk. He machined mine and I asked him for a drop in mine to help level my frame out with the usd forks, are you getting hime to machine yours?

Yes, here is the reply I got back when I sent him the pictures I posted here. Not sure his is understanding my question.

"My yokes would be flat, with no drop. By the looks of it, that is what you would need, as the ZX9 forks look long enough. My yokes would have the same stem offset, so your trail figure would not change."

If the Kz OEM upper yoke has a drop and both forks are the same length, then if you install the Kz stem into the ZX9R trees that are flat then the front end will be lower.

Kzstreetfighter71. How did you mock yours up and determine the drop needed?

kzstreetfighter71 wrote: Theses are the ones he did for me.

Comparing the stock photo to your it looks like all he did was take his stock upper yoke and machine it down to create the drop. Look where I marked up the stock photo with a red line. Viola now you have a drop yoke, not sure I like that. Yours is missing clamping force with only having 2 pinch screws vs 3.



I think I’m going to reach out to Les for a tree that actually designed for my application. Not a modified one size fits all.

Be aware that the ZX9R forks are not an equal diameter all the way up. For some reason they narrow towards the top and then come out again. So there is a slightly recessed area between the top and bottom yoke.
Probably not important with your planned set up but for anybody using fork extensions,its good to know.
Thats all. Carry on.

davido wrote: Be aware that the ZX9R forks are not an equal diameter all the way up. For some reason they narrow towards the top and then come out again. So there is a slightly recessed area between the top and bottom yoke.
Probably not important with your planned set up but for anybody using fork extensions,its good to know.
Thats all. Carry on.

Thank you for confirming that. I haven't remove my forks from the trees yet, but when shopping for them I was noticing what looked like a change in diameter where the fork would be pinched in the lower yoke was a larger OD vs the upper appeared smaller. I was just attributing that to the distortion of the photos.

The top triple clamp is smaller than the bottom on the 97 zx9 forks. The tubes are 51.9mm OD from the top down 180mm where there is then a 10mm long transition period to 52.4mm. If you use modified stock zx9r triples and mill off 20mm from the bottom, it leaves you 35mm between the end of the transition and the top of the lower triple.

So the max you can extend the top cap is 35mm, or 55mm with stock zx9r triples.

On my 650, I milled the 20mm off the top triple, and will extend the forks internally another 20mm to get to the proper fork length with the zx9r forks and wheel.

Edit: as far as calculating required drop, measure from the top of the fork to the ground (with the wheel/tire installed) for both setups and find the difference. That'll get you close. Suspension sag will have an effect here too, but should be similar in both cases.

Nearly all usd forks are narrower at the top than the middle, well from what iv seen anyways. When we were ironing out the design I asked for the loss of one bolt on the top and the absence of it gave me the drop, I was looking for any gains in height I could with the gsxr front end I have, worked well when I put them on for a mock up, I saw these type of tree on webike japan but not for my application. Send whom ever is doin the work everything, I sent Roy the gsxr and the z1 trees and he worked from them, cannot fault his work, it’s 100% perfect.

A pic of the clamps I saw on webike.

Viola now you have a drop yoke, not sure I like that. Yours is missing clamping force with only having 2 pinch screws vs 3. .[/quote]


Gsxr 1000 tree only has one bolt on top and 2 on the bottom, they seem to work fine for them?