V11 Gearbox leak

[ush1000]

Hi I have had my V11 for 3 years now, it had a gearbox leak when I bought it, and sure enough it still leaks now. From time to time I top up the oil and all is well. The bike gets very little use, I like to look at it and polish it and occasionally go for a blat. I now have some nice Mistral cans to fit but won't do this until the leak is fixed as the oil drips onto the exhaust crossover section under what I think is the clutch housing? Am I right in saying the clutch housing is dry and therefore the gearbox oil is leaking into this area through an internal seal? Is it possible to fix this problem with the engine in the bike or does it have to be removed? I am thinking about taking the bike to Corsa Italiana to fix and sort out the TPS and change the clutch fluid as I cannot free up the bleed nipple on the back of the engine.

Andrew

[GuzziMoto]

If the oil is dripping from the front of the gearbox/back of the engine it could be at least three different issues.

I would try to determine if you are leaking gear oil or engine oil as that would narrow down the issue.

First is the oil breather, which is near the top of the gearbox engine connection. If the rubber hose is cracked or not securely clamped to the metal fitting at the back of the motor it can leak. That leak often runs down between the gearbox and motor and comes out the vent hole in the clutch housing at the front of the gearbox.

Second leak source would be the output seal at the back of the motor where the engine output shaft comes out of the block. There is a seal there and it could leak.

Third source could be the gearbox input shaft seal. If that leaks the oil would have the smell of gear oil (usually rotten eggs).

There are other potential leaks near there, but those are the most likely three in my opinion to result in a drip at the junction between the engine and gearbox.

It is a dry clutch and there should not be any oil there.

Fixing it depends on the source of the oil. The breather issue is easy to do with the motor and gearbox in place. The other two usually result in either the motor, gearbox, or both, being pulled. It is not that hard to do, but first you need to figure out what type of oil is leaking (when I had a similar leak I replaced the gearbox oil with Royal Purple gear oil which is purple, or you could add some dye, or go by smell). Then try to find the source. Cleaning the area well then applying a coating of baby powder, which will make it easier to trace the source of the oil.

[ush1000]

If the oil is dripping from the front of the gearbox/back of the engine it could be at least three different issues.

I would try to determine if you are leaking gear oil or engine oil as that would narrow down the issue.

First is the oil breather, which is near the top of the gearbox engine connection. If the rubber hose is cracked or not securely clamped to the metal fitting at the back of the motor it can leak. That leak often runs down between the gearbox and motor and comes out the vent hole in the clutch housing at the front of the gearbox.

Second leak source would be the output seal at the back of the motor where the engine output shaft comes out of the block. There is a seal there and it could leak.

Third source could be the gearbox input shaft seal. If that leaks the oil would have the smell of gear oil (usually rotten eggs).

There are other potential leaks near there, but those are the most likely three in my opinion to result in a drip at the junction between the engine and gearbox.

It is a dry clutch and there should not be any oil there.

Fixing it depends on the source of the oil. The breather issue is easy to do with the motor and gearbox in place. The other two usually result in either the motor, gearbox, or both, being pulled. It is not that hard to do, but first you need to figure out what type of oil is leaking (when I had a similar leak I replaced the gearbox oil with Royal Purple gear oil which is purple, or you could add some dye, or go by smell). Then try to find the source. Cleaning the area well then applying a coating of baby powder, which will make it easier to trace the source of the oil.

Its gearbox oil, really smelly stuff. Sounds like engine out then.......probably off to Corsa Italiano

[Baldini]

Very common for v11's to weep a little gearbox oil onto the x-over box.

Mine did it - I checked all cover screws were tight & replaced gearbox oil with Redline Shockproof Heavy - no more oil weep.

 

KB

[Tom M]

Are you positive that the gear oil is coming out of the clutch housing? If not you might want to clean everything up then take it for a ride and check to see if the gear oil could be running down there from a leaky shifter plate on the starter side of the transmission. That would be MUCH easier to repair than the input seal.

[mznyc]

You can get a pretty good idea if there's fluid in the clutch housing by looking in the flywheel sighthole with a flashlight or pull the starter to look at the starter gear(better)

[ush1000]

Cheers guys, I am off to Zante for a week now, your replies have given me other avenues to explore! I will update on any progress made.

Andrew

[Trevini]

Very common for v11's to weep a little gearbox oil onto the x-over box.

Mine did it - I checked all cover screws were tight & replaced gearbox oil with Redline Shockproof Heavy - no more oil weep.

 

KB

 

 

I also has a similar experience. Turned out to be the rear cover screws worked loose. Bear in mind the gearbox oil isn't pressure fed (as far as I know, anyway), but a blocked breather could also cause weeps from seals etc.