Forks losing dampening while riding

I have a 06 YZ450F. I was riding my bike a couple weeks ago and the front forks completely lost their dampening. It felt like I was riding on the springs. I took the forks home and completely rebuilt them with an OEM Kit. I even replaced the cartridge seals and the ICS seal. I put the forks back together and everything was working great for about an hour and again I lost the dampening. Every thing is new inside the forks and they fade out. I took the forks apart again bled the inner chambers just to be sure and same thing happens in about 45 mins of riding. I'm stumped.

You cover the damper threads with teflon tape when you put the new seals in? Maybe you cut them during assembly? If you rebuild them again, when you have the inner damper out try compressing it and leaving it compressed for a minute or two and see if it still fully rebounds. If your loosing rebound then pressure is bleeding from somewhere and causing your problems.  Has to be cartridge seals or the ICS still leaking. Ive had good luck with synergy seals for the inner damper.

Bad seal, incorrectly installed seal, damaged damping rod, damaged floating piston rod, floating piston orings/bushings.

Edited by JS264

when you took out the cartridge did it have any oil?

If yes how much did the rod extend when compresed?

is it the same for both cartridges?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now