Are you saying the F3 shock was 9.3mm shorter than the original F2 shock? I remember reading something about F3 went with a different linkage/spring rate for 95/96 and then for 97/98 went back to the F2 rate. Maybe that why the F3 shock you have is shorter. I could understand why the 600rr shock is soft, probably because of the lighter bike that it comes on. And $15 for the 954 shock, its worth a try. If you have the money you really should get a Fox set up for you. One of the things about a stock shock is they overheat quickly when pushed hard on the track, then because of the heat the dampning pretty much quits working. Im glad you're gonna keep us updated. I'm very interested in you build/mods and how they work out.

 

Ya you are right the 95/96 is 282mm, the 97/98 is 293 the same length as a f2 shock. The linkage changed on 95/96 then went back to f2 linkage on 97/98 The spring rate on 97-98 F3s is .1 kg/mm stiffer than 95/96. When I was looking the f3 shocks were 50 bucks mine was 15. If I have any issues I'll just lower my forks 9mm to match. There is a used fox shock on eBay right now but I'm not willing to drop 275 bucks on it just to have to rebuild it. If money was no issue I would though.

 

I wanted to try a F4i shock just for the fun of it. I know it raises the rear like a inch and a half which is way to much. But I wouldve raised the front the same amount, to get some of the levelness back in the bike. Then after all that, lower the front 5 to 10 mm to get that "theroretical raise the rear 5 to 10mm" effect. But any how, Im rambling now. Just a little tip, be careful lowering your bike. A stock F2 will drag footpegs, gearshift, rear brake lever and sidestand when rode aggressively at the track. Been there, done that.

 

It seems like there's a little bit of "black mystery" going on in this thread. If one understands the function of a thing, then the design and adaptation becomes a matter of calculation (theoretical) and testing (practical).

The basic functional purpose of a suspension is to keep the wheel following the contours of the pavement, regardless of bumps and depressions (for the purpose of this post- which I'm typing on my iPhone, I will generally refer to all suspension systems the same, as equals and my post applies to forks and shocks alike).

The shock has 2 parts: spring and hydraulics (or pneumatics in really expensive stuff). The spring is the foundation in which the bike rests and it moves in response to Newtonian laws of action and reaction; stored energy and the release of energy. Without the hydraulics, the spring would oscillate until all energy has been expended back into the chassis. There is no way we could ride like this so we employ hydraulics to dampen or control the compression and rebounding of the spring. It's simpler math to dampen if we use a straight rate vs progressive spring but if we have the computational ability and sophistication of valving on the dampers we could use a progressive spring to change the rate of tension on the spring at different travel points along the stroke of action of the shock. All shocks work this way regardless of the bike they come from.

Because of chassis design goals and physical space limitations they employ linkages to change the leverage ratio of chassis to shock movement. The installation angles will also affect how much damping the engineers need to design at what portions of stroke.

I think what CF is tryout my tonsay is that you're getting into an area that may require parts fabrication and possibly changing the shock valves to get the proper action to make the bike safe to ride and perform the way you want. My hats off to anyone who pursues such a passion- your end product will be customized for YOU and not some mythical 160lb average rider.

 

I understand where you're both coming from. I was looking at my bike today and forgot to notice that my new clip ons are thicker than my stock ones by about 10mm. So in effect I had to push the fork tubes up that much to fit, therefore my ride height should be about level front & back. Albeit a bit lower overall. Then I may just lower the front a tiny more to give quicker turn in if I feel it needs it.

 

Keep in mind you could also put a shim (washer) under the shock mount to raise the rear. Ideal swingarm angle is around 12.5deg (IIRC)

 

The shock mount is welded to the F2/F3, so you cant shim the mount like you can on the F4i/F4, which has the bolt on mount. I've thought about that also. You could cut the F2 shock mount off and bolt the F4 mount on and shim it, couldnt you? Other than the F4 frame is square and the F2 frame is round, where the mount is.