Twin clutch oil problem

Paul Williams

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Non-VOC Member
Hi
I rebuilt my Rapide clutch about a week ago due to oil on the shoe's. Took it for it's second outing today and it started slipping again after about 10 miles. Got the bike home and striped down the clutch to find oil on the centrifugal shoes. When I rebuilt the clutch a new bonded plate was fitted,a dowty washer and non setting compound us on the shaft. This time the oil looks as if it is finding it's way past the carrier bush for the clutch drum. Any ideas.
Frustrated of South Wales lol
 

Bill Thomas

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Hello Paul, I have to keep my eye on primary case oil level, It could over fill from engine or gearbox, Or too much pressure from engine, The big oil seal can age and go Rock hard, Good Luck, Bill.
 

RedRyder

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Howdy, Paul - sorry to hear of this woe, but reach into that "iggy" or what is it y'all call 'em - "Eskys(?)" and grab a cool one. :) Bill is probably right on this, but, I would have a look at that "Dowty" seal. Is it VOC spec or a substitute? Regardless, if it is smashed (too much torque) it'll be no good, new or used. I am positive some folks use way too much torque on the nut. I believe it's enough to get the thing tightened to "grunt" force by hand, then back off if necessary to get the spring tine in a slot. Further, the shaft really likes to be cleaned then loaded with Hylomar.
 

greg brillus

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All you need is a bit of good sealant like Threebond smeared around the inner face of the nut before final assembly......works every time for me......no need for "O" rings/ dowty seals and similar. If you don't torque the nut up nice and tight, then something will give trouble down the track...at least 50 to 60 ft lb's on a nut that size. The nut holds the whole assembly firm against the mainshaft bearing and holds the G3 shaft hard to the left, so if the nut is just nipped up, movement of all these parts can be expected.
 

Paul Williams

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Non-VOC Member
Thank all for the advice. After I posted this I took another look at the clutch and noticed oil tracks leading out radially from the 6 screws that hold the drum in place. The other thing is there was no oil in the clutch/case just a very fine film on the clutch drum and shoes. The dowty was a VOC washer and it was not smashed on inspection. Any guidance on primary case oil level.
Cheers Paul
P.S I did reach for a cool one and it helped
 

greg brillus

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Paul, the chaincase level should be no higher than the level plug in the middle lower in the cover itself, just remove the 1/4 BSF bolt and the oil should drain off to that level. I have not found on my bike that an overfull primary leaks through into the clutch, but what it will do is leak from where the generator goes in, I suspect from too much oil flying around that the slinger arrangement cannot keep up. Once the level is lowered, the oil leak goes away. I have to drain the excess oil from my primary every 4 to 500 miles, or else it starts leaking quite badly from the back of the engine....not too difficult.
 

Bill Thomas

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Paul, I put a bit of RED stuff in the six screw holes, Were the shoe linings new or did you burn the oil off, If you burn the oil off it sometimes come back from deep in the lining when it gets hot, Cheers Bill.
 

BigEd

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VOC Member
VOC Forum Moderator
Thank all for the advice. After I posted this I took another look at the clutch and noticed oil tracks leading out radially from the 6 screws that hold the drum in place. The other thing is there was no oil in the clutch/case just a very fine film on the clutch drum and shoes. The dowty was a VOC washer and it was not smashed on inspection. Any guidance on primary case oil level.
Cheers Paul
P.S I did reach for a cool one and it helped

A few things that may have already been mentioned.
Primary oil level. Top up the oil and leave the level plug out until it stops dripping. The chain really only needs to just dip into the oil so that it gets flung around. If you engine has a lot of blow by the breather may struggle to cope so you are almost always going to get too much oil ending up in the primary case
I usually put a sealant of some kind on any area that could be a path for oil seepage.
If you drill half a dozen small equally spaced holes in the corner of the clutch drum oil can centrifuge out of the drum. I don't know if this done as standard on some drums. You can sometimes see a sign of oil on the drum running out radially from the C2 screws
Bill has already mentioned the PD 25 seal. It is a bit of a pain to fit a new one as you have to knock one of the bushes out first. If you don't have a new one fitted it is worth doing when you have the clutch dismantled as it is quite a lot of work to do later.
Check the diameter of the C3 carrier that the PD25 seal runs on. I had an oily clutch problem returning from a trip to Wales. I took some tracking down until I later found that the carrier diameter was slightly under size so that the seal wasn't able to do a satisfactory job. (I was also able to ride home on the primary clutch by being gentle with the right hand.:))
The clutch carrier nut and clutch carrier seal were modified so you need to get the correct seal type to go with the correct nut type. ( With an old bike you need to check that you don't have a mismatch of parts.)
I think Timetraveller described a mod using an "O" ring and a bit of machining or grinding to effect a better seal somewhere. I remember doing this mod but can't bring to mind at the moment how I did it. Perhaps he will see this and chime in.
 
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Paul Williams

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Non-VOC Member
Thanks all
Off to the garage for a another look at the clutch. Bill I cleaned the shoes last time by the detergent and boil method and then brake cleaner soak as an extra precaution.
 
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