Final drive front pulley oil leak

So I took the main cover off the final drive again for the third time and let the scoot run on center stand until it got hot enough to look for my oil leak. I finally found a small trickle of oil coming from the underside of the front belt pulley. I previously had taken the aluminum cover off and cleaned the oil and gunk up that was spread and caked through the whole unit. Nothing appears to have ever been on the belt nor the pulleys but oil and gunk was everywhere else, most looked old with very little fresh oil showing anywhere. The current trickle of oil is fresh looking and it slowly runs down the housing, it’s not being thrown out forcibly but I’m sure after a certain amount of buildup the turning of the belt causes the oil to be thrown through out which I’m hoping just looked worse than it actually was.
Im assuming that there is a front oil seal behind the belt pulley that is actually leaking. How difficult is it to change this seal? Right now it seems to be a small leak that of course will only get worse but is there anything I can use to swell the seal up more to make it last a while longer? I recently bought the scoot relatively cheap and don’t really won’t to put a lot of money in it if I don’t have to because it’s a 2003 with 67k miles. It looks almost new and runs very strong and smooth, only issue at all is the little drops of oil I get from final drive area usually after each hour+ ride.

I have some pics that I have taken of my oil leak issue but I don’t know how to post them.

If the oil is coming from the shaft which holds the front pulley assembly then it sounds like an engine strip down. If my memory serves me well, that is the crankshaft oil seal which leaking. It sounds like an unusual failure so maybe other members have some ideas?

I have some pics and finally figured out how to post them. Maybe someone can look at these and tell me what’s going on. The first 3 pics is before I cleaned it up.


Thanks

This one I let it run for half hour and got it good and hot. Very little oil drip noticeable under belt side front pulley.

Engine oil leak very rare at this spot like Loosemarbles stated. Crankshaft seal.
Pretty sure it's an external seal that can be replaced without major engine work. Looking at parts diagram Crankcase. #18 91201-MCT-003 other parts might be needed #11 collar 15156-300-003 collar, # 20 91302-pc9-003 O-ring.

Left belt case-swingarm removed should be access to the seal. I don't have my service manual handy at this time to look it up.

I’m still riding it almost everyday. I would like to at least wait till cold weather to take it to my cycle wrench for the fix. Is there chance of some kind of catastrophic failure if I continue to ride it without replacing the seal? There is no obvious oil loss reading from checking the crankcase oil and the final oil is level at this time also.

It's not getting on belt so no problem there just keep engine oil full it will be fine.

Before you take anything apart, make sure oil level is correct in the engine, when checked on center stand, with cap/dipstick not screwed in all the way, etc. Too much oil in engine can push out that seal. Replacing that seal is kind of a major job, to access it, the whole left swingarm assy., has to come off and everything that's attached to it, etc. This video below gives you an idea, everything in that CVT case is potentially contaminated with engine oil, IMO.

https://youtu.be/UXl6e4r-tEY?si=2H6uwRX2a_SDeDzC

Thanks Mech, I’m going keep a close check on the engine oil and just ride. No oil has been on belt nor the pulley plates but it does get distributed over time everywhere else in the final casing.

zrx, thanks for the video, it sure puts everything in perspective. I’m not real mechanical and looking at the video I will definitely have to have it done by a knowledgeable mechanic with the correct tools. Im not going get in a hurry and just keep a close eye on the oil level.