Stupid Hydraulic clutch

[arcboy]

Well I was out riding on my 00 380 EXC and everything was great but then the last 10 minutes I noticed the clutch was slowly getting worse. I thought it was pumping up or at least when it was in it was slowly being pulled closer like it had air in the system. Eventually after about 10 minutes I had no clutch. There is still mineral oil in there and I see no leaks. I read somewhere in my search that its possible to have a bad o-ring in the slave and it leaks into the case. I tried to search fo this o-ring but I couldn’t find it.

I think this is the last KTM I ever own. I don’t like how these KTMs are designed. I am trying to sell it and get a YZ250F, I’m a Yamaha guy and I’m flipping this thing. This is waaaayy too much bike for me and it runs and looks awesome. I tried racing a 250F and I tried everything and couldn’t keep the front wheel on the ground, crazy low and mid power.

[swedishfishmx]

Good luck.

[gmoss357]

So, let me understand, you are upset that your 11! Year old dlbike developed an issue and blaming the manufacturer for a failed part. When was the last time you serviced the hydraulic clutch?

You are going to have problems with any bike of age or with lots of hours.

Stupid KTM, my bottom end went out after only 500 hrs, good grief, it was only 7 years old.

Fix it and ride, or buy a new bike if you want less issues, but don't diss KTM because your 11 yr old bike has problems. Geez..

[stonezone]

I had the same problem on my 2006. Easy fix, just open it up and see what part is damaged. I had scoring in the cylinder so it needed to be replaced (cheap off ktm-parts or similar).

good luck with that yammy. I came off blue and although I loved it, I'll never go back...

[Rider 41]

So, let me understand, you are upset that your 11! Year old dlbike developed an issue and blaming the manufacturer for a failed part. When was the last time you serviced the hydraulic clutch?

Are you supposed to do that??? ?

[markit]

These are pure race bikes, sure if you just trail ride you can ease up on reg maintnance a little. I do fluid and seal kit ever 6 mo clutch/F brake but i race. Rear break every race. Its actually amazing?? 11 years.lol

[lespaullover13]

i agree with gmoss. ive rode kx yz rm and cr. my 300 mxc beats em all in the trail without breaking a sweet. The bike requires maintenance just like any other. the difference is how they perform in the trails.

[MadMatt46]

...a 380 2t that cant beat a 250 4t??? your bike must be tired. i've come off a yz 250 2t, and i'll never go back(unless yamaha could build a 300 of the same calliber). my 08 300 xcw has a few isues, but what used bike doesnt?

unless its maticulously maintained from new, and ridden real soft, theres no way a used bike can be issue free - ESPECIALLY an 11 year old bike

[arcboy]

Ok maybe you guys are a little too sensitive towards your KTMs. I never said I didn’t do any maintenance and I never said this is a piece of crap that has been falling apart.

I never said that a 250F could beat me because the 380 was too slow, I said it had a ton of low and mid power and couldn’t keep the front end on the ground and keep it from flipping over to beat him. I am just too small and light to handle this beast in these tight woods in the carolinas.

I think that KTMs are great bikes just don’t like some of the designs compared to other manufacturers. A lot of parts that are attached seemed to be to more difficult to remove. I don’t like a lot of the plastic parts like the rebound knobs and the plastic A/F screw.

Anyways, if you are able to help me in my diagnosis without rebuilding everything that would be great. I didn’t want to spend $100 on seals and fluids and still end up with a broke clutch and a headache.

Thanks

[975]

I had similar problem with a magura clutch, but when it happened, it leaked all of the oil. A big part of the problem is that the o-ring of the slave piston was too small and the piston would scar the cylinder. I had to "bore" the cylinder to remove the grooves and install a new thicker o-ring. That fixed the problem definitely.

[trailmeisterjoe]

Ok maybe you guys are a little too sensitive towards your KTMs. I never said I didn’t do any maintenance and I never said this is a piece of crap that has been falling apart.

I never said that a 250F could beat me because the 380 was too slow, I said it had a ton of low and mid power and couldn’t keep the front end on the ground and keep it from flipping over to beat him. I am just too small and light to handle this beast in these tight woods in the carolinas.

I think that KTMs are great bikes just don’t like some of the designs compared to other manufacturers. A lot of parts that are attached seemed to be to more difficult to remove. I don’t like a lot of the plastic parts like the rebound knobs and the plastic A/F screw.

Anyways, if you are able to help me in my diagnosis without rebuilding everything that would be great. I didn’t want to spend $100 on seals and fluids and still end up with a broke clutch and a headache.

Thanks

? sheesh! we are talking about an ELEVEN year old bike. thats equivalent to a 25 year old car.

Joe

[ktmfred300]

Maybe you need to go buy that Yamaha and see how much valves are when they burn up.

[MadMatt46]

....funny, my mate just bought a 200 after me telling him why i bought a ktm.

he's just stripped the bike, to have the frame powder-coated...and he is TOOO STOKED at how easy these bikes come apart and how easy they are to work on.....??? guess its up to the individual. good luck with ANY 4t you go with.....

[swedishfishmx]

Buy some seals and re-bleed the clutch. You should be good to go and only cost you about 50bucks.

[stroker]

A lot of people seem to get really excited with hydro clutches. I have been racing for many years. I always carefully maintian my bikes.

I have NEVER had an issue with a cable clutch.

Several times I had issues with hydro clutches.

Cables are lighter, cheaper and easier to fix/adjust and deal with, they also have a MUCH better feel than a hydro clutch IMO. I do not understand the fixation with hydro clutches.....

[ktmfred300]

Cables work fine if maintained but if the clutch is worked hard the engagement point changes that's where the hydro clutch works better. The engagement point never changes. The point is that his problem can be fixed cheap. And how old is the bike? Sorry but I don't think a Jap bike holds up as well when negelected. And what Jap bikes comes with a hydro clutch thats not a street bike. NONE.

Rant over.

[dirtbeater]

I love the hydro clutch. My bike is an 04 and I have yet to do anything to the clutch. The rear brake is really starting to make me mad though. Wish they went with the good old drum design.

[Gary jp4]

Well I was out riding on my 00 380 EXC and everything was great but then the last 10 minutes I noticed the clutch was slowly getting worse. I thought it was pumping up or at least when it was in it was slowly being pulled closer like it had air in the system. Eventually after about 10 minutes I had no clutch. There is still mineral oil in there and I see no leaks. I read somewhere in my search that its possible to have a bad o-ring in the slave and it leaks into the case. I tried to search fo this o-ring but I couldn’t find it.

I think this is the last KTM I ever own. I don’t like how these KTMs are designed. I am trying to sell it and get a YZ250F, I’m a Yamaha guy and I’m flipping this thing. This is waaaayy too much bike for me and it runs and looks awesome. I tried racing a 250F and I tried everything and couldn’t keep the front wheel on the ground, crazy low and mid power.

Ok maybe you guys are a little too sensitive towards your KTMs. I never said I didn’t do any maintenance and I never said this is a piece of crap that has been falling apart.

I never said that a 250F could beat me because the 380 was too slow, I said it had a ton of low and mid power and couldn’t keep the front end on the ground and keep it from flipping over to beat him. I am just too small and light to handle this beast in these tight woods in the carolinas.

I think that KTMs are great bikes just don’t like some of the designs compared to other manufacturers. A lot of parts that are attached seemed to be to more difficult to remove. I don’t like a lot of the plastic parts like the rebound knobs and the plastic A/F screw.

Anyways, if you are able to help me in my diagnosis without rebuilding everything that would be great. I didn’t want to spend $100 on seals and fluids and still end up with a broke clutch and a headache.

Thanks

Dude, calm down. Take a pill. You're all over the place. Most of that has nothing to do with your problem or getting help. Try to focus on the clutch for a minute and you will get better help.

The o-ring in the slave could be the problem as you said. It is not listed in the parts list (at least on the newer bikes) and apparently they want you to buy the whole slave cylinder. You can get the o-ring separately from KTM though, as they use the same one other places. Or you can get one after market (McMaster-car part numbers given). This has been posted on hundreds of times and is in the "KTM 2-Stroke FAQ" in a sticky at the top of the page and then in there under "General FAQ Information" and then in that page about 1/4 of the way down under "Bleeding hyd clutch:". Read it. I will give you the part number's for the ones used on the newer bikes and the sizes (see below) out of that section but corrected as one of them is a misprint in there. Take yours apart and measure the piston groove. O-ring's are sized to the ID of the o-ring or OD of the part they fit around.

There is a good chance the bore of the slave cylinder is worn oversize and in that case a larger o-ring and some sanding of the bore may clean it up and make it usable. This is also covered in that section and in many post if you search here.

Don't forget the problem could also be the master cylinder needs a rebuild kit.

O-ring options (the ones that say "oversize" are for repairing a worn slave cylinder)

Clutch Slave Cylinder cover O-Ring O-RING 30,00X1,50 KTM P/N 0770300015

Clutch Slave Cylinder O-Ring 23.52 X 1.78 mm KTM P/N 0770020210

Clutch Slave Cylinder O-Ring 23.52 X 1.78 mm (McMaster-car) P/N unkown, Look it up if you want one from McMaster-car

Clutch Slave Cylinder O-Ring (oversize) 23.00 X 2.00 mm KTM P/N 0770230020

Clutch Slave Cylinder O-Ring (oversize) 23.00 X 2.00 mm McMaster-car P/N 9263K502

You can go to your dealer and buy one of the KTM part numbers using these number or go to one of the online dealers and plug the number in.Having a 1990 bike you need to know how to do that. If you don't, then ask and ye shall receive.

Previous threads:

https://www.thumpertalk.com/forum/showthread.php?t=774872 This one shows a slave cylinder with wear and gouges (typical) and a repair of a worn slave cylinder.

https://www.thumpertalk.com/forum/showthread.php?t=825844&highlight=slave+cylinder+clutch+oversize

[arcboy]

Ok, so besides the fact of what bike I choose to ride and this particular KTM is in excellent shape and has hardly been ridden.

I have bought the outer o-ring and the piston/o-ring combo.

New problem. As I bleed it I can get all the air out, at least I think, it seems to either be fully engaged or fully disengaged. There is no scaring. I think its impossible to put the piston in backwards and it is a really tight fit.

Going to attempt it again tomorrow.

[FC Sparling]

Just picked up a 2010 400 XC-W with 14+ hrs. on the meter and 215 mi. on the OD. Having some of the same issues. Very difficult finding N, when in gear clutch fully engaged and hit the start button bike lunges forward as if the clutch is not engaged.

? Is this probably the O-ring in the slave piston needing replacement?

Any advice?

FC