04 525 EXC clutch info / advice


I have a 04 525 EXC that is CA. Plated. and I have ridden it twice, and the clutch is slipping. (btw it only has 2000 mikes on it). I have been riding since I was 12, and am 46 now. . . and have NEVER fried a clutch. My last bike was a CA Plated Honda CR500, so I know I ride it a bit like a 2 stroke, but I am not at all abusive to it in any way. . . so. . . :lol:

I am curious what people are using. My local dealer (Z Racing) says use the stock ones, because of the thickness. I know there is Barnett and DP. . . Barnett has been around forever. . . any input would be great.

BTW I ride CA desert mostly. The plate is so I can ride single track in the local mountains. . .


Big Dave

i dont know much about ktm clutches other then there not bad...

i would not put barnet friction plates in unless your sure its not going to drag.

get ktm or ebc

Always best to go with OEM parts. I would buy stock fiber plates, and soak them in engine oil. While the new fiber plates are soaking clean the metal plates with brake cleaner and then buff with fine wet sand paper on a flat surface like a piece of glass. Re-assemble and go ride that thang!!


The first thing you need to do is crack your bleeder to be sure the slave or master is not hanging up, then replace with OEM parts. Like was stated they are good. CJ

I was told they (ktm's) need the correct distance in the clutch pak or there will be issues.

ALSO my metal plates are all glazed, and was the cause of the slipping, so I want to replace them as well.



Very odd, I've had 5 ktm'S and have never replaced a clutch in any of them, what kind of oil are you using? i'd go for the OEM stuff, I ride the crap out of my 04 525 and it still works flawless, just over 200 hours on it.


I know! I have NEVER had to replace a clutch. . . EVER yet in two rides on this bike. (again, I bought it used with only 2000 miles). . . But STILL. . . this isnt the 1st used bike I've had, and I KNOW I didnt slip the clutch THAT much. . .

I will just use the OEM. No one so far has reccomended using a aftermarket one.

the plates are so thin that they can warp. Its common to flat sand them while checking for warps. Only needing to replace the warped ones. Knock the glaze off and ride. There are different thicknesses for the different years so be sure you get the right stuff if buying new.

What oil are you using? If you use an automotive synthetic with frcition modifiers - that will do exactly what you are talking about. I run Mobil 1 synthetic Twin 20-50 (for cycles only) and no problem. The most recent issue of Dirt rider says the plates can "mushroom" (they don't specify the model year) but I don't know if that would cause slipping.

Nobody is reccomending an after market clutch for KTM's because the OEM clutches are that good. They seem to last forever.

Being that this is a used bike, I would think it is something the PO has done to it. Either running automotive oil in it or maybe putting lighter springs (like out of a 250) in the clutch assy. to get an easier lever feel.

I think I would pull the clutch pack and start inspecting. Look for warpage and glazeing.

(what kind of oil am I using) I am using Maxima Synthetic as per recommendations by Z-Racing here in Orange.

HOWEVER. After buttoning it all up, starting it, (couldnt ride because it was 11:30 pm ) I loaded it up, drove out to the dez, and hopped on. Started it, let it warm up, pulled the clutch in, clicked it into gear. The bike clicked into first gear, I let the clutch out. . . then nothing.. The bike didnt move. It was like the clutch was still pulled in.

The ONLY THING I can think of is Z Racing didnt give me enough plates. I didnt count them. . . I assumed it was the correct amount. . . SO, back in the trailer it went.

At least I didnt have to clean it after I got home.

will keep you all updated after I pull it back apart.


Big Dave

Should have 7 friction discs and 8 drive plates.

I'm going to concur with most of the others here who say the OEM clutch is stout. I have 300 hours (12 000 kms) on my 05 525 and I just measured the factory clutch plates. All are very well in spec.

If your clutch was still good before your last two rides, then I'm afraid you might have an issue somewhere that will likely wear out the new clutch if it's not fixed.

Sean :p

I'm sure it may have to do with the slave. because after removing the cover, I noticed the plates were movable within the basket. . . there is a ball within the slave cyl. and its not supposed to come out, but we'll find out tonight

yes there are the proper amount of plates (8 steel - 7 fiber) They are supposed to measure 21.8 - 22 mm overall thickness. . .

thanks all!

its like a mystery!. . . a whodunnit!

Big Dave

also- probably not but - check that you put the clutch springs in right...

wasnt aware there was a wrong and a right. . . they look the same on both ends. . .

but thanks. . . I'll dbl ck that


First check is hand gaurds! If the lever so much as touches the hand gaurd you have trouble!, Next is the link adjustment at the lever, you need to understand how a master cylinder works, lever pushed a link, link pushes the piston, piston is in a cylinder, the cylinder in under the reservour and there is a tiny hole or port from Res to the cylinder. It is abosutly imperitive that the link not hold the piston is too far so the piston covers the hole! If it does it is not going to work right!

Next issue, there where changes inthe clutch in 06, if you mix 06 parts with 05 you can get in trouble, example the push rod is longer in 06!! So has anyone been inside?

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