Teach me - fork oil

[fastdruid]

Originally Posted by thefallenangel

but if it's up on a paddock stand and held in situ then what can change.

You don't know where you've started from. That's why I say measure it as per the manual then pop springs in and measure again, that gives you a base to work from.

Druid

[fastdruid]

WRT to suspension tuning, stolen from http://www.peterverdonedesigns.com/suspension.htm

.5. Set approximate rear ride height.
1a. set Oil Height to the minimum height.
1b. Reduce rear shock nitrogen pressure to minimum spec.
2. modify the Oil Lock Piece - for race, eliminate or practically eliminate effectiveness of the oil lock piece. For street, reduce the effect of the oil lock piece if under hardest hit, more than 3mm of travel is left unused.
3. Spring Rate (& Sag) - this is done by changing springs (and preload).
4. Slow Speed Damping - this is done by changing oil viscosity and in some cases, slow speed orifice and needle size.
4.5 Straighten fork tube - these can be slightly bent. straighten the hell out of 'em.
5. High Speed Damping - this is changed by changing valves and/or shim stacks.
6a. Oil Height - this change tunes the last 1/5th of travel. Raise the oil height from the minimum if the fork is bottoming or practically bottoming.
6b. Rear shock nitrogen pressure should be raised in 25psi increments only to prevent cavitation.
7. Fine tune rear ride height for corner exit. Fine tune front fork clamp position for corner entry.
8. Re-sag bike.

Druid

[fastdruid]

Originally Posted by fastdruid

Secondly weight, lol. Weight isn't really the best of things to describe fork oil, its rather inconsistent and basically has issues.

WRT oil 'weight' http://www.peterverdonedesigns.com/lowspeed.htm

I'll hot link the table in just to show:


Also see http://www.peterverdonedesigns.com/damping.htm on the differences between damper rods and cartridge/shim stacks.

Druid

I'm going to be stripping the forks on my CBR to get them powder coated soon. Can I re-use the seals even if I do that? I don't have a clue what the innards of the forks actually look like so that might be a stupid question. Will find out soon enough though, just want to check what bits I need, sounds like just oil if the rest is in good condition?

[yorkie_chris]

These are RWU forks right?

If so you should be able to reuse seals, bushings etc. Just replace oil.

[fastdruid]

Honda fork seals are cheap[1]. The grief of replacing them is immense. Odds are you'll ruin them taking the forks apart though.

Druid

[1] I don't know what model you have but CBR600F6 ones are £26, 'busa are £67!!

[yorkie_chris]

Why ruin them? Slide hammer forks apart after removing clip, chances are they'll go back in OK.

[punyXpress]

Silly question, but what's best to flush mayo & coffe grounds out of forks?

[yorkie_chris]

Steamed milk

[punyXpress]

Latte?