99 WR400F -- Installed new clutch, Can't actuate clutch at all now...

Hey everyone.

So I have been doing a bunch of maintenance lately on my WR400F. New piston not all that long ago (ridden since and working fine) got it plated through some DMV black magic, and finally decided to replace the clutch. I got a full clutch kit (fibers, plates, springs) and went about the process in a pretty standard fashion. I dumped all of the oil, got a new filter for the bike, and then pulled the clutch cover. I undid the bolts holding the springs and hub in place, and pulled that all out. I then pulled all the fibers and plates out, and was careful to not touch the rod that actually presses out on the clutch hub to disengage the clutch. I then replaced the plates in the ame order, and they are all the correct size. I put the hub back in place, put the springs in and bolted everything down. I filled the bike with oil, ran it for a bit... and that was when I noticed that I went to grab the clutch and it had ZERO resistance. Odd... but I thought maybe it was out of adjustment. So I went to adjust it, and come to find out no amount of adjustment in the world was going to get it right.

So... any ideas anyone on what I may have done wrong here? I put the bike on it's side and pulled everything apart again to see if perhaps I could fix it that way. Everything was in there in order, the rod was in place and I could get it to actuate a little bit by reaching over and manuplating the clutch mechanism on the riders left side... but still... when I put it back together I just couldn't possible adjust the bike enough to get full disengagement.

Any advice anyone? Any help is appreciated. I'm rather stuck and am now having to take my MX bike on trails for a ride tomorrow instead of this. Thankfully, I own three bikes :)

Let us know if your running a Hydro-clutch or Auto-clutch? Did you use OEM or Aftermarket clutch parts? I prefer OEM, as I've had issues with aftermarket clutch parts causing the same issues as you are currently having.

Did you soak your new fiber plates in engine oil for several hours before installing them? It not, they may not have expanded to the correct size.

Other than that thought, count what came out vs. what went in, check your manual to be sure you're in the right order but I'd bet you didn't soak the plates before the install.

Edited by miweber929

When i put a set of new clutch plates in my wr250 i could not operate the clutch.

I removed the clutch cover and gave the clutch housing a tap with a hammer and everything sprung into position. It must have been caught on a ridge or something.

I have done 2000+ miles since then and every thing is fine.

I didn't soak for 24 hours, just a few hours. I'll pull them out for a 24 hour soak, along with trying the hammer tap and everything else mentioned thus far.

I did go with aftermarket (Tusk) as I wanted the stiffer springs and nicer fibers. Pulling out the OEM stuff it was clearly low quality and why it all burnt out relatively quickly. I've installed a lot of clutches in my days, and these are particularly weak sauce OEM clutch fibers.

Hi mate,

I gave my reply last time without reading your question, but after reading your question in detail this is exactly the same as what found with the wr250.

When i put everything back together the clutch was stuck in its out position.

I did a little video showing the movement when it was fixed.

I am 99% sure if you drop the oil it will just take a tap inwards or even up or down slightly to fix. Just a tap with a metal hammer.

Lets us know if it fixes the problem.

Good to know. I'll try this tonight. I've also learned that I can lean the bike over on it's side with the fuel off and get into the clutch without dumping the oil. Normally I wouldn't care... but I did use some mighty nice amsoil for this oil change!

k im replacing the whole clutch in a rm 125, i got the basket and all the fibers back in line, put the springs in, and put the cover back on, in the book it says to inspect the clutch play, but when i do that there is just a freeplay of about a quarter inch, and no clutch or squishy up and down play, what do i do????

I just went thru this same scenario and thought I'd share my solution.

Changed my clutch discs to find that there was no tension on my clutch lever, didn't feel like it was engaging the clutch. Certainly wasn't letting go. Pulled the clutch cover off and noticed that the pushrod was moving (~.100"), but not contacting the pressure plate until the very end. It was separating the plates, but just barely. All this will the clutch cable adjusted out as far as possible, till the push lever couldn't rotate any more.


Well it turns out that the friction plates are not all the same size, the one against the pressure plate needs to have a smaller ID so it clears a lip on the pressure plate. I had them in the wrong order and the last friction plate was sitting on this ledge on the pressure plate.


Probably basic knowledge for a lot of guys, but you don't know what you don't know. Took me 3 hours to figure that out. Thought I'd capture it hear, and maybe save someone else some grief.


Recap, place the friction plate with the smaller inside diameter against the pressure plate.

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