1975 KZ 900 , ZRX Swingarm, 89 GSXR front end

Thats the money you could be saving on GIECO....

bumpppppaaa..bummpppappaaa..

This shock mount just sits around the shop starring at me!!

I just measured my free sag and static sag . It seems that the zrx shocks springs are tooo stiff. this may be due to the fact that i laid the shock down to set the ride height lower. i could put the lower mount back into the original mount but this would lower my front rake. the steering seems fast now. I was sure my rake was about 24* but now it measures 26??? maybe it changed since I played with the front preload? it sure feels fast.
I think i may as well try raising the rear, just to see. this will allow me to see if the proper sag is achievable as well.
Maybe u could make a lower mount with 3 mounting locations so u can play with ride hieght. that was my reasoning for having the lowering link. or just tack yours on and check the sag and rake? how long are your shocks? mine are 14 1/4"

Shocks are 13 3/4" eye to eye.

The ZRX is about a 500 pound bike (i dunno what that is in Kilos.....ahh you metric Canadians!!) the KZ all lightened up should be about 425-450 dry.

The rake should have gotten better with the lowering of the rear end. If you are good enough to check the rake, maybe look at trail. From what I understand, that will also help to stabilize the bikes steering. You just dont want too much. Trouble with that tiem is it generally means a new tree and top clamp.

www.rbracing-rsr.com/rakeandtrail.html



I am looking at the link you have there, noticing the shock could do a little free play dance. I am wondering if this brief moment of freeplay has anything to do with the wobble.

www.rbracing-rsr.com/advchoppercalc.html

Check this out, ignore the harley crap, if you put your dimensions in here, you get what you are looking for.

I just cant remember the optimum trail figure. i think its a formula of sorts, i come up with around 5 inches of trail. but I input number from memory, so that could be off a bit.

Just reviewing the sales specs for new bikes, you can get an ida of what is optimum.

Rake (fork angle):24.5°
Trail:94 mm (3.7 inches)

So I just started seaching the e-mail machine/www. machine and it tells me the specs on an R-6 Yamaha sportbike. The r-6 or any 600 is gonna have the most extreme front end set-up. As trail is reduced so is stablity (typically).

Based on what you have ridden in the past and how it felt to your style of riding you can find what you want.

My Ducati Monster has 24 degree rake, and 4.7 inches of trail. It feels pretty stable, until you hit some rumble iee stuf, then it does a short headshake dance.

I got used to it, and softend up the front end which helped alot. On a typical track day I put about 100 miles on the odometer. I might feel this happen once or twice.

Your blank posts are freakin' me out man. Yes I lurk. Troy341

The zx9 weighs 475LBS dry, rake = 24, trail= 93mm
kz = 528lbs., rake = 26, trail= 90 mm.
ZRX12 = 492lbs.

i jacked the rear end up into the stock shock mounts.3" higher.each inch at the rear = about 1* of rake. this increased the rake from 26 to 22.5. That is STEEP!, of course this will reduce the trail as well

I took it around the block. the steering felt fast before, now its a lot faster.:woohoo:
I didn’t work it hard yet. I need to find a good road.
I did have a hose clamp on the shock laydown bracket. I know what u mean about it possibly shifting a bit. I was concerned myself. from the small ride I don’t think the issue has gone away. it may be worse. Too early to tell. it defiantly took some confidence away from me when I measured 22.5* rake.the best ting i could do would be to find shoter shocks so i can remain at 26* or 27* of rake.
I know a lot of guys put shorter forks on front and the zrx setup at the rear and don’t complain. but now I wonder how hard they actually push there bikes? this runs fine if u don’t push it, but what fun would that be.
I think I will run a chalk line down the driveway and test for front wheel to rear wheel alignment. as u suggested, this may be an issue.Its hard to find a spot = on both sides to measure the rear wheel alignment.
I will have to measure the trail and see where i am, but with the shocks laid down it should have been close to 90.
I looked at the calcultor but i dont know the offset #?

Offset, i am assuming you mean fork offset, which is the distance from the steering stem forward to the fork tubes.

Just lay a straight edge across the center of the top of the fork tubes, then measure back to the center of the steering stem nut.

I really wanted to make the upside down forks work with mine, but I had a couple people (341) (stoppee) convince me the ground clearance issue was not worth it.

I am glad i stuck with the conventional forks, there were enough other things to take care of.

.....Troy...it freaks me out when my posts are blank too...

I had to go to the Microsoft website and correct a little problem :woohoo:

how long are your forks?
When i put the shocks into the original lower mounts(more upright), i regained the sag. the springs are not bad in the upright position(sag = 20mm), and too stiff when laid down(sag= 13mm). but i need shorter shocks or longer forks to regain the rake. the ground clearance is not bad.

mark and tk11b40,do you guys think that we could take the zrx shocks and remove the eyelet from the chrome rod end and shorten and re-thread and just buy a race tech or eibach or whoevers spring and get where you want to be?
just thinkin .
leon holmes

no not on these anyways. the eyes are part of the dampers.

look real close at em mark,they had to get the springs on somehow.

leon holmes