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Discussion Starter #1
my pop has a sp1 .sometimes the clutch when clutch lever released.causes a bucking,surging.regardless of how slow you release the leaver.most times its very smooth never slipping. its very weird how seldom it acts up. its original,clutch 13,000 miles.clutch pivot was greased,fluid was flushed this year.62 year old driver
 

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RC51's will do that around certain rpm's. Welcome to 1990's motorcycle fuels injection technology. I'm guessing this usually happens in town around 3k rpm's while trying to hold a steady speed? A powercommander with a custom map can smooth it out a bit. Or just downshift.
 

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I think he's talking about what my SP1 does on rare occasion. As you ease the clutch out, it will suddenly grab and launch forward, unless you're real fast and pull the clutch lever back in. Have you thoroughly cleaned your slave clylinder (including the seals and cups) and have fresh DOT4 in there? If so, just change your engine oil. Honda HP4S, Mobil-1 4T, and Amsoil are all good choices. I've used the first two. When my oil gets near time to change, my clutch will start to do that rare judder/launch. Change my oil and it goes away till I've got at least 2000 miles on the oil.

I think this is called judder. And I think it's a SP1 thing. The SP2's have a judder spring/seat in the clutch plates/discs, that I understand was to address this. Not real sure on that, but I haven't yet heard of SP2's having this problem.

I'll change my original clutch of 24K miles, out this winter. I'm going to use a Barnett kit; plates, discs and springs. Hopefully that will cure it, cause altho it happens rarely, it's a little unnerving...

Hope after all that, my diagnostic was right?
 

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Mine was doing that a while ago, I had a look and noticed the last clutch plate wasnt indexed but after putting it right it still did it.It only did it at a certain temp so I warmed her up to that temp then dropped the oil, which was really airated and seamed to have excessive viscosity.I changed it out to Mobil 1 4t 10-40 and never had a problem since.(my 929 used to do it to, untill I changed it also to mobil 1)
 

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I think he's talking about what my SP1 does on rare occasion. As you ease the clutch out, it will suddenly grab and launch forward, unless you're real fast and pull the clutch lever back in. Have you thoroughly cleaned your slave clylinder (including the seals and cups) and have fresh DOT4 in there? If so, just change your engine oil. Honda HP4S, Mobil-1 4T, and Amsoil are all good choices. I've used the first two. When my oil gets near time to change, my clutch will start to do that rare judder/launch. Change my oil and it goes away till I've got at least 2000 miles on the oil.

I think this is called judder. And I think it's a SP1 thing. The SP2's have a judder spring/seat in the clutch plates/discs, that I understand was to address this. Not real sure on that, but I haven't yet heard of SP2's having this problem.

I'll change my original clutch of 24K miles, out this winter. I'm going to use a Barnett kit; plates, discs and springs. Hopefully that will cure it, cause altho it happens rarely, it's a little unnerving...

Hope after all that, my diagnostic was right?
The judder spring on SP2 was to correct the abrupt take up engagement (judder) of the SP1 clutch. It allows for more smoother, more gradual engagement.
The judder spring, seat, and friction plate are interchangeable with the SP1.
 

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@SubSailor, I remember talking about this before, almost word for word. I was having the exact issue back in Feb. And if one would install a factory SP2 clutch disc set, into a SP1, that whole grabby issue should dissapear.
I never got around to changing my clutch yet, cause changing the oil to a top quality solved the problem for me. My clutch never slips, so must mean the friction discs are still ok. Even so, this winter, if the rain ever starts for us, I'll install a Barnett kit for half the price of OEM.
 

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Discussion Starter #7
you hit it jondog.its funny how seldom it does it.works great before and after the abrubt engagement. oil is change with castrol cycle oil 10-40. at 2,000 mile intervals. should i change oils, or do clutch swap? the clutch master cylinder was flushed,with fresh fluid.never gets a muddy look.
 

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Since your milage is that low, and you're sure the seals and fluid are ok, I'd just change the oil. I tried Honda HP4S 10w30, and instantly my shifting was better and no grabby. But at the dealership it costs around $14/qt. Mobil-1 4T 10w40 was my second pick at $10/qt. It performs just as nice as HP4S for me.
 

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Mine does this too on occasion. New oil or 3000 mile oil. I agree it must be temperature related, as it has never occured when bike was fully warm. First time scared me to death-so I went to the net to find it is pretty common. Not a pretty thing when leaving pit lane! Good to know about the SP2 retrofit mod to cure it when clutch time comes around. Thanks.
 
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