Julian;
"thunking" - more than one potential cause for "topping out" or
"thunking".

1) bearing migration .. cannondale has a tool that measures migration
and brings them back into spec.. easy to use/quick

2) spring in the air piston has worn bushings/torn o-rings. .. easy to
inspect once the cartridge has been removed.

3) the cartridge itself... many different things.. leaking around
o-ring seals, cracked shim, inadequate oil charge, etc.

If your shop has lots of experience with headshoks.. it will be
easy/quick to fix.

the fact that your lockout no longer works indicates to me the problem
is with the cartridge itself.

I'd be interested in knowing what the fix was.

charlieb

On Wed, 09 Jul 2003 14:41:41 GMT, Julian
wrote:

I have a Cannondale Headshok Ultra Fatty on a 2000 Jekyll.

On a ride yesterday it started making a loud "THUNK" when coming off a
log, or rock. It's like the rebound damping is super-slow and not
letting the fork return quickly enough. When it does pop back out, I
hear the "thunk" as the fork tops out. At least, that's what I _think_
is going on in there.

I also noticed that the lockout doesn't, anymore. And if I turn the
lockout "on" then the damping is even slower, with an even louder
thunk.

Any thoughts on what might be causing this?

It's going to the shop in a couple of hours, but I'd like to get 2nd,
3rd, etc. opinions.

Thanks all for your help.