[trialsguy]

I've been riding the fork for a year now and have never found it to be plush. I just overhauled the fork and installed 5wt oil. (I did have to replace the spring washer in the rebound leg and fill the rebound cartridge) but it's still a harsh ride. The compression damper is completely backed out as far as it will go.
Tried a Sachs '08 fork on a gasgas 250 and found it a more plush ride.
I'm guessing but I think it's the compression damper.
Has anyone made any internal changes to the fork that has made it more plush?
Thanks
Andrew DeBoer
Whistler, BC, Canada
www3.telus.net/andrewdb

[yamahaty250xox]

why dont you try 2.5wt oil. It can make a big differnce.

[laser1]

How much oil did you put in?

As a long shot, Make sure the fender brace isnt causing forks to bind. Are they smooth off the bike?

[JSE]

yamahaty250xox, on Jul 27 2009, 07:26 AM, said:

why dont you try 2.5wt oil. It can make a big differnce.

Try the 2.5 weight just on the compression (left) side to see if that takes you in the direction you want (always change just one variable at a time to be able to accutately evaluate the results). The nice thing about the Marzocchi forks is that the rebound and compression is in different sides so the oil viscosity can be individually adjusted to fine tune the damping action, forks that have both damping assemblies in the same cartridge (like some forks that only use one spring) will have both compression and rebound changed by oil viscosity adjustments.

The adjusters at the top are essentially "high speed" tuning adjustments (they are usually a needle valve, or in some shocks, a varible orifice, and work by allowing a variable amount of fluid to "bleed off" after a certain pressure is reached) and work with the higher damper shaft speeds (like a big hit on a rock that quickly accelerates the shaft through the cartridge). The main damping process is dictated by the "shim stack", or set of special washers on the piston that travels through the cartridge, and that is not adjustable unless you substitute a different set of washers or change the diameter of the holes in the piston (a job for a suspension pro with special equipment).

I agree that fork bind is always the first place to look when dealing with suspension problems and it is usually free to fix, just taking a little time. If the adjustments do not solve the problem, it might be a good idea to disassemble the forks and inspect the bushings and upper tubes . Binding forks (sometimes caused by a bent fork tube) will wear the bushings quickly and it's difficult to tell if that has been a prior condition.

Jon

Quick edit note: The oil level is critical in the Marzocchi's and they really should be set by oil level rather than volume or you will often end up with too much oil (and harsh damping on the comprssion side).

This post has been edited by JSE: 27 July 2009 - 03:55 PM