Bonneville America Forums Forums Technical Forums General Tech Me thinks I have "that oil leak".

Ok guys, I know someone else found an oil leak near or aroudn the front sprocket. I didn't see one when I changed my sprocket, but it was WAY dirty in there, figured it was just chain goop.

But the other symptoms I get are in keeping with what others have said. A couple drops on the garage floor after a ride, looking like it dripped off the filter. I also noticed, while changing my pipes, that my right side pipe was WAY dirty in the bottom/back side of it.

So my question is, if I take off the sprocket cover, where should I be looking? I'm thinking of taking a ride, and then immediately taking the cover off and checking. Also, I know my oil cooler has a weep to it, but my oil level has dropped WAY more than a little weep, so I need to keep an eye on it, ya know?
As always, and once again, thanks!!!

I thought I had an oil leak back there a few years ago. Turns out it was just excessive chain lube building up then dripping down...

Benny, I had a "leak" from my filter too, but it was good and tight. I wiped it off and it came back. Finally, I removed and throughly cleaned the area under the cover, as well as the inside of the cover, and the filter, and the "leak" vanished. I knew it was crank oil though before that, since it smelled like the Scott Oiler oil, not crankcase oil. My bet is that if you thoroughly clean the underside of the bike (be careful about the electronics black box bolted to the front bottom of the rear wheelwell), as well as inside the sprocket cover (I just wiped it very clean with a bunch of rags, but Kerosene would be easier), and then watch it, I think you'll see it wasn't a leak (I hope).

Well Greg, I did the filter leaning and cleaning under the sprocket cover when I changed the sprocket. Used carb cleaner, rags, a nylon bristle brush, etc. Got it good and clean too.

FJ, I doubt it's the chain lube, but I'll pull the cover and check...

I remember someone having a leak from a seal around the sprocket shaft or something that would drip down and onto the filter, as if it had come FROM the filter, but actually higher. I need to lift it WAY up and get a good light under there and see.

Make sure it's not just blow-by from the airbox drain tube. I've had some oil appear on the filter that was dripping out of that tube after a hard ride.

I had the oil leak from the seal behind the sprocket last year. I replaced the seal. I just rang up my dealer and he sent me a new seal. Its no biggie to replace. Just drilled a small hole in the old one, be carefull not to go to deep. and using a small screw into said who pull it out. Pop in the new one and your off. The seal has no taper to it so be carefull installing the new one or you will pinch it. Assuming that this is your problem. If not nevermind.

Benny, I lubed the chain but didnt know to wipe it. After riding for a while I stopped and noticed what looked like oil leak coming from the sprocket. Best way is to smell it. Chain lube smells weird like crayons. I removed the sprocket cover and cleaned it. Now I wipe the chain after every lube.

Trash, I think that's it... So it's an easy fix? That's good. It's definitely not chain lube, at least not ALL chain lube, cause it happens no matter how long after a chain cleaning. Plus I've had to put in about a quart of oil over the course of the summer.
Plus I don't have an airbox anymore:) And I know my breather isn't leaking, checked it. Thanks for the advice tho guys!! Gives me ideas where to check.

I had a leaking sprocket oil seal which caused the same symtoms as you described - small amount of clean oil dripping on the garage floor after a ride but not a continuous drip, oil drips from filter after running down from the sprocket area. The leak got worse over time and was actually blowing up on my saddle bags and all over the exhaust. My dealer fixed it under warranty and said that the new seals that they were getting from Triumph were of a different improved design.

Thanks gooch. My warrenty is WAY over, but I'll see about getting a new seal and see if that does it. Sounds like I could replace it myself.

An improperly tensioned (tight) chain could cause the sprocket seal to deform and leak, as well as other more damaging effects in the gearbox. Keep that chain more loose than tight.

Make sure the plugs are in the ends of the airbox drain hoses. Those can dribble a little oil condensed from the crankcase vent right into the area you are seeing oil.

I've got about an inch of slack when I lift the chain...

Greybeard, no airbox to do the dripping...