Been thinking- fork swap

[BrentMartell]

ICS stock is around 2.1 on the 05 showa. Racetech suggested 1.76 for MX and I went with a 1.6 FC IC spring. I assume they are very much a like. I did the same with a buddies 05 Honda 450R. 1.6 spring, 350cc oil height, and reshimmed the entire system to a much more compliant fork. I rode the bike a couple of weekends ago and it was very good. I could race that bike just as it is.

Having said all that I am not sure how the CC affects the sag issue. Technically the inner chamber just holds fluid and the rod moves through it. I would think, in a non-mobile state, the fork would sag under the bike and or rider weight in the same fashion as any other until it came in to the spring holding the weight up. Which reminds to bring up the point of spring length. The more coils you have the more there is to move, right?

LOL, this is like tying to figure out how a woman thinks....well much easier. ; )

 

[GMP]

The ICS spring/piston travel would be proportional to the oil displaced by the rod for the given fork travel. So, you could calculate the distance the ICS compresses for this volume or travel, and calculate the additive effect of the ICS spring rate.

 

[BrentMartell]

You could be right. I am not seeing that spring having a much of an effect on holding the bike up. It is relatively easy to push that rod up and although there is some return force it is not significant. I have the forks off again in an attempt to build a spacer so I will pay more attention to the affect the ICS has on the ability to hold the bike weight up.

One way to find out would be to remove the inner assembly and check the sag. Hmmm

 

[GMP]

Yes, you would think it had little effect. The additive spring rate effect should all boil down to: (damper rod area/floating piston area)ICS Spring rate.

 

[ghill]

For anyone interested, I have a couple of Showa and KYB front ends for sale at the moment:

1) '06 Honda CRF450X fork legs, triple clamps, axle, and spacers/lockrings for the steerer tube. MINT shape. <10 hours total. Full lathe polishing on the fork legs, bushings and the internals. Silly smooth. Fork bleeders. 1.2 IC springs, 0.42 Eibach springs (have 0.46 springs and 1.6 IC springs as well).

2) Complete front end off a 2006 YZ450F (KYB SSS system) with front axle, brake, clamps, etc. Can sell with or without wheel. 0.47 KYB springs, stock IC springs, new SKF seals. Fresh fluid. Fork bleeders.

I don't check in here real often - please email gordon.stuart.hill@gmail.com