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XR400 Clutch Slip - What is normal?

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I just put a new clutch kit (including clutch plates and springs) from DP Brakes in my 97 XR400 hoping it would eliminate most if not all the clutch slippage I was experiencing. I thought my problem was due to normal wear and it was just time to replace the clutch after 9 years. After the install I have noticed some improvement but but not what I was expecting. The springs that I installed with the new kit were taller than the ones I replaced and the new clutch plates looked better than what I replaced. As far as clutch adjustment, it seems to be fine. With the lever pulled all the way in the clutch does not drag and I can shift to neutral at a stand still with no problem. There is plenty of play when the clutch lever is released. The lever has a very short pull. When the lever is about 3/4 of the way released the clutch is fully engaged and remaining is free play. Is some slippage normal for all XR400s? I am running 14t front and 47t rear sprokets. The slippage I am experiencing occurs in 3rd, 4th, & 5th gear under heavy acceleration. It is a combination of wheel spin and clutch slip but the clutch always catches up after a couple of seconds.

When I ride my son's YZ250F it feels like there is no clutch slippage in any gear until you pull in the clutch lever.

Any feedback would be appreciated?

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I agree with XRay, none is normal. What oil are you using? Some automotive oils have moly and other stuff in them that doesn't go well with oil bath clutch. Suggest you try going back to Honda 4 stroke oil and see if that problem clears up.

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Not normal.

Did you install the friction plates correctly (one not "in line" with the others). Check the manual.

Check if the clutch arm on the engine has some free play ( to check for clutch cable binding).

Did you also replace the clutch steel plates?

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These guys are correct that it is not normal. You have to be very careful that the clutch plates you bought are at the top end of the tolerance scale because the XRs are very sensitive to this. I returned a brand new clutch kit because it was in the middle of the range(new), and that was where my old(slipping) clutch was. The next brand I bought was great and has never slipped

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Even if you put the worst energy conserving oil in the bike, you wouldn't have slippage like you are describing. That whole car oil/energy conserving oil thing is 98% urban legend anyway.

Somewhere you have a binding cable, pivot point, or clutch arm that isn't giving you free play.

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I'm curious, did you soak the fiber discs in oil over night before install?

Did you happen to measure the old springs length?

Did you happen to measure/compare the thickness of the new fibers with the thickness of the old ones?

Is current lever pull as easy or easier than it was before clutch and springs replacement?

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Thanks for all the input. Yea I thought that a new clutch kit would not slip at all for a long time. Especially since I don't fan the clutch at all, I just pull the clutch when I shift. In tight stuff I let the grunt of the XR400 do all the work.

Here are answers to the questions:

I am using and have always used Honda 4 stroke 20w50 oil.

What I did by step follows:

1. Drained the oil and removed clutch cover, clutch springs, and clutch plates.

2. I compared the old parts with the new. New springs were noticably taller than the old ones. The new friction plates looked a little better than the old (meaning more friction material). The new clutch plates looked identical to the old. I didn't measure anything just did a quick visiual, thinking I just needed to make sure I had the right parts and that if new looked better than old I'm good.

3. I inspecked the wear on the clutch basket. There was a little but not much. You could just barely feel bumps where the plates have been rubbing. I always thought the symptoms of a worn clutch basket is the clutch does not disengaging which is not my problem. I thought for sure the new springs would solve my problem of clutch slippage and I went ahead with the install.

4. I soaked all the plates in Honda 20w50 oil before I installed them. I put them in the order according to the service manual.

5. I checked the lever at the clutch cover and it has play when the clutch lever is released and I don't see any binding in the cable.

6. I added Honda oil and did a test run.

Overall the new clutch performed only slightly better than before.

I did notice that the clutch lever is a little easier to pull now, which I expected it to be more firm with stronger springs. I am not sure if I need to do everything over with another brand of clutch kit or is it just the springs. Any suggestions on brand of clutch kit. I assumed the DP Brake clutch kit exceeded what came stock in the XR400s, but maybe not. I have also heard of people installing washers on the top of the clutch springs on some Yamaha 250fs to add more strength to the clutch springs. Has anyone tried that on an XR400?

Thanks again for the feedback.

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I did notice that the clutch lever is a little easier to pull now, which I expected it to be more firm with stronger springs. I am not sure if I need to do everything over with another brand of clutch kit or is it just the springs.

See, that's strange to me too. When I replaced my clutch springs with heavy duty springs, I was like WHOA, lever pull effort increased almost 2 fold.

What makes you say they are "stronger" springs? Were they advertised as heavy duty or something or just going by the fact that they are longer than the originals? They are HDS28-6 springs. Not sure if the HD stands for heavy duty or harley davidson, as that same spring has harley applications too.

All clutch springs may not be created equal.

Did you tighten the springs equally, a little at a time in a criss cross pattern until tight?

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xr400's have barely adequate clutch's to start with, 440 kit/pumper carb and it'll slip, try replacing your clutch springs, they make stiffer springs

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........I did notice that the clutch lever is a little easier to pull now, which I expected it to be more firm with stronger springs.,,,,,,,

I personally would try the OEM springs before ordering new parts. The longer springs may be softer. No need to drop the oil, just lay the bike on its side...

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Sounds like a good idea GU520. I have the original springs that I could put back in and try, but I already ordered a set of Barnett heavy duty clutch springs today hoping that would fix the problem. I will probably do like you said and just lean the bike over put in the new springs and see what happens. Hopefully the stronger springs will do the trick.

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