Final Drive Sprocket FF model

Peeps, Im finally getting round to looking at why Ive got an oil leak from the rear end of my engine - because its getting a little better with the weather and I should have done it last year but didnt. Anyway, I havent had the bike very long and after I took off the clutch master cyl cover to get to the drive sprocket I think I should have found some kind of guide ring and damper bolted up against the sprocket ? However, with mine there was just the 14mm central bolt to hold it on and nothing else. I can see there should be a small O ring there as well ? Is the lack of these bits causing my leak do you think or was that only on certain models ?


hi martin,
nice to here from you, ive just noticed the exact same problem on my bike a few days ago, a small dribble of oil which lands on the collector box then burns off, i dont think the guide ring which fits to the side of the front sprocket is crucialy important and often gets disguarded as some aftermarket sprockets dont have the 2 holes to secure it, the “O” ring is important as the crank is hollow all the way through to the sprocket bolt, i normally use some semi-setting gasket seal on the threads of the sprocket bolt…
to be honest though, ive had the same oil leak a few times over the years and its normally been the 2 big oil seals located behind the sprocket, or the gear selector seal.

OK Pete, thanks for that reassurance. What about taking that inboard case off ( the one in your picture ) Im guessing Ill need to drain the engine / gearbox oil before removing that ? I want to be sure the gasket between it and the main crankcase is sound. Does the water pump need to be removed at the same time to access it ?
Sorry about all these silly questions but my “Workshop Manual” is a factory one - as supplied on this web site, and really only tells you the various measurements and data etc and not how to do things. I suppose that`s because if its meant for a factory trained technician they expect you to know how to get to and take off the various bits.


I have the same problem on my VF/G… I’ll have a close look at “La revue technique” of the VF and I’ll tell you.

hi martin/ fred,
yes it seems to be a fairly common fault, i think it sometimes goes un-noticed other than the slight puff of smoke as it burns off the exhaust which can often be mistaken for chain lube,
yes the water pump needs to be removed and the oil drained down,
the 2 large oil seal sizes are 40x58x9 and 40x62x6, i normall just order them from any of the online oil seal manufacturers, also theres a couple of small o rings on the flip side of the casing, watch you don’t misplace them.

Exactly, Pete, I can see them on the drawing on “la revue technique” (french equivalent for Clymer, Haynes or Chilton manual).

You need the small O ring behind the sprocket retaining bolt head at least. The damper ring is not totally necessary but makes for less back lash. I think they are available from cms in Netherlands
If you can’t find a ring I have a spare you can have.

Thank you gentlemen, your help is very welcome. I will remove the inner bearing case and check all the gaskets and O rings before replacing the 2 x larger seals.
Lets hope that sorts the problem - oh and Ill make sure I replace the small o ring behind the main sprocket bolts. Like Pete says, Ill add a smear of silicone to the threads to make sure.

Thanks guys