Question on possible drive sprocket seal leak...

[Resto_Paul]

Developed what I think has to be a leak on my bike this weekend. I thought it was chain lube slinging off but it seems like way too much especially since it just started and its been a bit since I sprayed the chain. It's extremely dark like grease and my oil still looks brand new. I tightened the chain tensioner a bit about 50 miles ago and I'm wondering if I overtightened and if that could have possibly damaged the seal?? I'm going to back the tension back off a bit but I don't see that magically fixing it now right?

 

[Jan_P]

Well sometimes it can get better after a while .If I remember right it is fresh rebuilt
Slacking the chain and drive some see what happens.
i tend to wait but end up replacing later. But not always. But are used to leaks
depends on how much
Autolube of the chain

 

[Resto_Paul]

Well sometimes it can get better after a while .If I remember right it is fresh rebuilt
Slacking the chain and drive some see what happens.
i tend to wait but end up replacing later. But not always. But are used to leaks
depends on how much
Autolube of the chain

Yeah the bike is spotless so anything that drips on it is annoying. It's enough that its leaving a small spot after riding 10 miles. I'll back the chain tensioner off later and ride it to a show next weekend about 50 miles round trip and see. Definitely don't want to split the cases again already.

 

[AUTOMAN]

Yes over tightened chain puts more load on output shaft/bearing which may bend it enough to create leak.

Back the chain to normal 1" slack.
Put Blue devil in the case to swell the seal.

Temporary fixes at worst.

 

[Jan_P]

Yeah the bike is spotless so anything that drips on it is annoying. It's enough that its leaving a small spot after riding 10 miles. I'll back the chain tensioner off later and ride it to a show next weekend about 50 miles round trip and see. Definitely don't want to split the cases again already.

Can be the clutch rod seal also
I give it a fair chance to stop leaking .But you don't need to split the cases Normally
When the cases are opened the seal is put in place .But not when assembled ..motor in frame
Maybe it depends on the seal.

I use a Bicycle spoke - stainless a little stronger and make / bend a small hook getting behind the seal ..
like an L shape or so But other ways is usable.
Pulling with pliers on the spoke getting the seal out Taking care not damaging anything.
If I remember correct holding the spoke nearer the Axle which is harder.
And then use a small piece of pipe is it 2 inch rounded edges tapping the new seal in place
Well greased up so it slides in.

 

[GLJ]

Check and make sure the counter-shaft sprocket is tight. It has to be very tight, 96 foot lbs I think.
I use my impact, I let it hammer 3 times. I know my impact pretty well I've had it for over 40 years. On the other hand I am crude. Haven't had one leak yet.

 

[Resto_Paul]

I'll try loosening it later today and see if it slows down or stops over the next few rides...maybe I'll get lucky.

 

[5twins]

But do check the countershaft nut to make sure it's tight. It's pretty common for it to come loose, even with that lock tab washer on it. And as GLJ said, it needs to be very, very tight. I used to use 72 ft/lbs on it but every time I'd be under that cover, I noticed streaks of oil on the sprocket emanating from the shaft. It wasn't actually dripping but it wasn't 100% sealed either ......

Upping the torque to around 95 ft/lbs fixed it, no more oil streaks ......

 

[Miker Vee]

But do check the countershaft nut to make sure it's tight. It's pretty common for it to come loose, even with that lock tab washer on it.

Heiden Tuning offers a transmission bushing with an O-ring which should face the gear shaft.
That way the oil is kept in by the O-ring and shaft oil seal, and no longer relies on the contact area of sprocket to bushing.
Part number: 39-30200.

Picture from their website:

I bought one, but didn't try it yet. Seems like a valid idea though.

 

[Resto_Paul]

I'll start with loosening the chain.....it was the last thing I messed with before the problem started a few miles later. If that doesn't work I'll try snuggling the nut down more....but the way my pipes are designed I probably have to remove the left side pipe to get the cover off and it's a bear to put back on