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Clutch Inop. '09 KTM 250SXF

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Tiny D and I fooled with it until 11p last night.

I just bought a used '09 KTM 250SXF for the boy and have roughly 5 hours on it since we bought it over Thanksgiving, poking around the Spillway so Tiny D. can get used to his new trusty steed.

Back home we went through the bike checking the fluids. Noticed the clutch fluid was low so I mistakenly added magura blood instead of brake fluid. Well, two days later I discovered that the magura blood caused the rubber sealing bits and pieces to swell which warranted replacement parts. (Chalk it up to my own foolishness for adding the wrong type of fluid)

Here's the problem that's stumped me and caused a lot of disappointment in a little boy.

In gear, engine off, clutch lever pulled in the back tire is locked up while rolling the bike back and forth. At first thought, you would think air is still trapped in the system, but we properly bled the system, a-la Turkey Baster, and here aren't any bubbles in the system.

I pulled the split ring retaining clip and plunger at the Master to confirm the two seals were not folded or creased, bled from the bottom up with a turkey baster and tube--no bubbles.

The wheel was still dragging to the point that it would skid on the concrete as I rolled the bike back and forth.

I let the bike sit overnight with a zip tie holding the clutch lever depressed to the handlebar think it might encourage other wayward bubbles skyward.

While in gear at idle with a Rekluse installed on my YZ450, the rear wheel still wants to roll, but you can stop it from doing so with very light hand or boot toe pressure, this is normal, on the 640A, same thing-the wheel moves, in gear, clutch in, engine running, light hand/toe pressure stops the wheel. But on the 250, the tire is locked up completely when rolling back and forth, clutch in, while in gear, engine off. I might be wrong, and correct me if I am, but this doesn't feel right.

I'll head back out once the coffee does what it is supposed to do and start her up and knock it into gear to see if it stalls, but what else could it be?

No riding for us today unless we can cast out the demon.

Dirty

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. I do know that the 250s have a very draggy clutch. Mine is very hard to push in gear when motor isnt running, it gets better when it is warmed up, but still drags. The lower seal in the slave may be shot and it just isnt working right now tho after the oil was added to the non oil system. Have you guys ridden it yet to see if it starts working again?

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Mike- We did replace the O-Ring on the slave piston. The other bellows seal that is mounted on the slave piston is fine.

I can understand a bit of a drag on the rear wheel, but it won't turn at all-engine off, clutch in, in gear.

The slave piston acuates the rod that goes to the other side of the engine where the clutch basket sits, I can't help but wonder if it could be something else...surely not.

A clutch system is a fairly straight forward component-and to have this sort of an issue befuddles me.

Dirty

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Probably started it in neutral, warmed it up, dropped it in gear and all was fine. Hell I can't roll my '01 Cr250r cold in gear either.

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Team- like we should have in the first place, we bled the system from the slave up to the master cylinder using mouth pressure/hose with a turkey baster pushed onto the end attached to the bleed valve on the slave. Works like a champ now.

Started right up, popped her into first and the bike lurched forward just a tad, but free'd itself from most forward motion from the inherant clutch plate drag almost instantly.

Don't tell anyone, but Tiny D was in tears (displayed to Mrs. D not me) that his new-to-him bike wasn't working right. But such is life for a 13 year old with a new toy itching to go ride.

Dirty

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Team- like we should have in the first place, we bled the system from the slave up to the master cylinder using mouth pressure/hose with a turkey baster pushed onto the end attached to the bleed valve on the slave. Works like a champ now.

Started right up, popped her into first and the bike lurched forward just a tad, but free'd itself from most forward motion from the inherant clutch plate drag almost instantly.

Don't tell anyone, but Tiny D was in tears (displayed to Mrs. D not me) that his new-to-him bike wasn't working right. But such is life for a 13 year old with a new toy itching to go ride.

Dirty

Glad to hear you got it sorted out guys! Merry Christmas!! :bonk:

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I don't understand how Magura blood, which is basically mineral oil could harm seals?? Brake fluid is more caustic than mineral oil.

I have an '07 450 and I put magura oil in it. I hope that's correct.

I think I may need to bleed mine. Doesit need to be bled when you pull the cylinder off the side of the motor?

Would a horse syringe would do the same thing to inject fluid and bleed it??

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I don't understand how Magura blood, which is basically mineral oil could harm seals?? Brake fluid is more caustic than mineral oil.

I have an '07 450 and I put magura oil in it. I hope that's correct.

I think I may need to bleed mine. Doesit need to be bled when you pull the cylinder off the side of the motor?

Would a horse syringe would do the same thing to inject fluid and bleed it??

The '09 250F bikes (at least ours) has a Brembo Master cyl and Slave. Brembo's use brake fluid as the clutch system juice. Magura systems use the Magura Blood, aka red-colored mineral oil.

Magura Blood like we used doesn't play well with the seals in a Brembo system. Hard lesson learned.

Stupid me didn't notice the print molded into the top cover of the master cylinder on Tiny D's new bike-and therein lies the problem. In big print it said to ONLY USE DOT 4 BRAKE FLUID.:bonk:

Who else finds it hard to read the instructions? Am I the only one out there?

Dirty

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haha, don't beat yourself up too bad. sometimes it seems logical to assume; like using mineral oil in a hydraulic clutch. I did , and I still don't know....

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