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I had a clutch failure on my '03 LT with just shy of 150K miles. Tonight I pulled the slave and found the c-clip that holds the plunger/bearing/spring assembly inside the slave had blown out and was laying in the access, resting on the clutch push-rod where the slave seats. As I pulled the slave off and the last screw was removed, it shot off like a rocket from the spring not being held in by the c-clip, releasing additional dot4 fluid. Having not been inside the bike here before, is the c-clip failure what caused the dot4 fluid to be introduced to the seal? Had that clip not come out, would the dot4 have remained behind the plunger assembly? Or, does the leaking o-ring allow the dot4 fluid to break down the metal material of the c-clip and it just eventually pops?

The night it failed, I was about 200 miles from home so I kept chugging since it was all interstate. I noticed a nasty smell of fluid burning (couldn't tell if it was trans or dot4) each time I was traveling up-hill, but the smell subsided considerably when I was on level ground or moving downhill. I plan to replace the entire clutch, clutch slave and trans seals but was looking for some validation on the smell. At this point, I'm unsure if it was dot4 or gear lube that screwed the clutch.

Thanks,
Bob
 

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Bob, I think from what others have told me, is that the displaced C clip will have been as a result of the slave piston rotating in the bore of the cylinder whilst in contact with the clip. When the slave fails it is actually the little thrust bearing which siezes, then the rotational forces are transferred from the clutch push rod into the slave piston, causing it to rotate and it eventually tears up the slave bore, which wrecks the seal and allows the fluid out. You possibly smelt fluid which was getting cooked as the piston spun/stopped/spun etc. When you purchase the new slave unit, take some time to carefully examine the thrust bearing. See if it's able to be re-lubed it is quite small and it eventually fails as it rotates at engine speed continuously. Hope this helps, Dennis.
 

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Hi Bob,

I would agree with Dennis and do not see any way that the dot4 would have caused the metal to breakdown.

If you are in the market for a complete clutch assembly, I have one that I purchased as a spare. It came from an 07 that was retired after a deer hit.

Mugz
 

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Wrencher Extraordinaire
2005 K1200LT
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The c-clip loose is a new one but the release rod would have held the piston back far enough that no fluid would normally leak. The clip's only purpose is to hold the slave piston in until you install it. Fluid did not cause it to pop off.

Hard to say what went first as tranny seals don't like dot 4 and slave seals don't like gear lube. Either one will take out the other. Just best to replace both.
 
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