When is a clutch "burnt"?
I have read other threads about a burning smell from the clutch (like this one). What I would like to understand, having no experience with damaged clutches whatsoever, what's the consequence of that smell?
The "killer" was a steep incline, felt like 45 degrees (and was probably not much less) plus two sharp switchbacks. I was scared s***less and the bike stalled halfway up. Restarted it, revved high (that's when I briefly noticed the smell) and crept up the rest of the hill with brute force.
- Is it the smell of death: once it happens, better get the plates exchanged lest you risk a sudden break down in the middle of nowhere?
- Or is it more like: forget about it, just don't do it too often?
The "killer" was a steep incline, felt like 45 degrees (and was probably not much less) plus two sharp switchbacks. I was scared s***less and the bike stalled halfway up. Restarted it, revved high (that's when I briefly noticed the smell) and crept up the rest of the hill with brute force.
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Takes a lot to kill one of those clutches.
The only sure killer is badly adjusted so it's slipping badly, anything short of that it'll take a lot of abuse even to wear it significantly.
I've done an hour or more straight slipping the clutch continually in second and third several times. I did replace everything at 110,000km, but going by wear on the plates had at least another 20,000k's (and that's assuming the thickness's were at max when it was new - unlikely)
Pete
The only sure killer is badly adjusted so it's slipping badly, anything short of that it'll take a lot of abuse even to wear it significantly.
I've done an hour or more straight slipping the clutch continually in second and third several times. I did replace everything at 110,000km, but going by wear on the plates had at least another 20,000k's (and that's assuming the thickness's were at max when it was new - unlikely)
Pete
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it doesn't harm a wet clutch to slip it at lower engine speeds, I put litteraly hundreds of miles on single & 2 track trails standing on pegs, slipping clutch in 1st n 2nd gear, also parking lot manuvering, I got 102k on my origninal SV650 clutch riding this way
ya shouldn't me smellin it thought, thats indicative of higher speed slipping necessary for burnouts & wheelies
ya shouldn't me smellin it thought, thats indicative of higher speed slipping necessary for burnouts & wheelies
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How would hot clutch smell get out? The clutch is sealed in the engine case, bathed in oil, and the sealed crankcase is vented to the air box where the vapors get burned in the combustion chambers.
As Randy and Pete said, these clutches are designed to be slipped. Do check that the cable is adjusted so the clutch is fully engaged when the lever is released. And just ride. If it fails, you have a warranty claim. An early oil change on a new engine is always good to remove the break in particles too small to be caught in the oil filter.
As Randy and Pete said, these clutches are designed to be slipped. Do check that the cable is adjusted so the clutch is fully engaged when the lever is released. And just ride. If it fails, you have a warranty claim. An early oil change on a new engine is always good to remove the break in particles too small to be caught in the oil filter.
Thanks to all for the helpful comments!
The oil was changed at 500 miles. Will be changed again soon. I always keep my clutch adjusted to about 1/2" of free play (it actually had a lot more now as the wire seemed to have stretched a bit).
I wish I could tell more exactly what happened on that hill, but I was too focused on not sliding down backwards... But either way, it seems like nothing to worry about.
The oil was changed at 500 miles. Will be changed again soon. I always keep my clutch adjusted to about 1/2" of free play (it actually had a lot more now as the wire seemed to have stretched a bit).
That's a fair question. I just went by what others have been reporting, and it seemed plausible -- I was revving high to avoid another stall, and the bike was hardly moving. The only other possibility is that I was actually spinning the rear wheel without realizing it and may have burnt some rubber.
I wish I could tell more exactly what happened on that hill, but I was too focused on not sliding down backwards... But either way, it seems like nothing to worry about.
Clutch, not chain. Spec = 10..15 mm (1/2" or one finger thickness for field use ;-)).
You had me worried there for a second, though. :mrgreen:
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Oh, you mean the clutch lever end. Yes, I was reading faster than my comprehension allowed. The important clutch adjustment is under the front sprocket cover. As clutch material wears, the pack gets thinner and uses up free play between the push rod and clutch actuator. Loosen lock nut #3 and back out the adjuster #4 at least one full turn to assure separation. Then lightly turn #4 in until it contacts the push rod underneath. Then back #4 out 1/4 turn to allow push rod expansion when hot. Finally, hold #4 in position and tighten #3. Adjustments at #5 and #6 as well as at the clutch lever are just cable adjustments, not clutch adjustments. That 1/2" at the clutch lever end is not critical. As long as there is some free play and the clutch is totally disengaged when the lever is pulled, the lever can be set to the rider's preference. The position of #4 is critical.
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Thinking more about HSL's adventures with his clutch, even if that extreme slipping didn't fry the clutch, it might have broiled the oil. Oil is damaged by high heat, and this might be a good reason to dump that oil. If a small sample of oil looks clear and smells clean, probably OK. If it got black quickly and doesn't smell like clean oil, I'd dump it. Heat causes the oil to oxidize, and oxidized oil doesn't protect the engine well. Synthetic oil is more resistant to oxidation, one of the reasons for its longer service life.
Thanks for the additional thought. The bike will be in the shop Wednesday for some warranty work (which in and of itself might cause more damage than the clutch episode
rig_rolleyes. They'll most likely have to pull the starter clutch which means the oil will be dumped anyway. It sure doesn't look clear anymore (after 2k miles) but then it didn't before the trip, either.I am pretty certain that what you 'smelled' is not the wet-clutch. As described in past posts, it is nearly impossible to smell a wet-clutch.
However, it is VERY possible you smelled the exhaust pipes. A catalytic converter can run at over 500 degrees. When you are running your wee at slow roadspeed / high RPM conditions, the exhaust pipes are very hot. There is very little cooling-air blowing past the exhaust.
Any water or mud thrown on the exhaust can let off odor.
I would bet this is what you were smelling.
However, it is VERY possible you smelled the exhaust pipes. A catalytic converter can run at over 500 degrees. When you are running your wee at slow roadspeed / high RPM conditions, the exhaust pipes are very hot. There is very little cooling-air blowing past the exhaust.
Any water or mud thrown on the exhaust can let off odor.
I would bet this is what you were smelling.
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