I have a 2000 FXSTB and for about two years the inner primary has leaked copus amounts of oil. I've replaced all the seals and gaskets at least 4 times and I cant figure it out it only leaks when I'm riding. After I park it the oil that has been thrown all over drips off I can wipe it down clean up the oil on the floor and not another drop will fall no mater how long I let it set. A harley tech sugested that it was building pressure and a vent of some type would cure it. Tried that and still the oil bath continues. I dont think the inner primary is cracked I've looked in vain to find a crack but there just isnt one there. A small amount of oil dosent bother me but when tis dripping off of the rear fender after 70 miles It starts to. Thanks for any sugestions.
Sam

 

I am no mechanic but my RK has a vent hose on the transmission next to the primary.Trans overfilled?
I am sure some one more knowledgable will help you out.

 

No, I've determand that it is defnatly primary oil with dye.

 

Do you know what spot it is leaking from? Have seen 'em that were warped and no amount of new gaskets, seals, or gasket goop would fix them. Or a nick on a seal surface allowed the oil to run by when it was sloshed around while riding.

 

Not leaking from gasket between inner and outer primary cases.

 

Just replaced my stator and pulled off the inner primary because of an oil leak. I found an impact hole on the back of the upper inner primary must have picked up a rock or something the oil was dripping down the back of the inner primary and down to where the drain plug is.
took it off got it welded no more oil leak. makes sense bike is idle no leak. bike is running oil is coming out of the hole. Hope this helps

 

Sounds like you have a void (crack or hole) in the casting edge where the seals go and it's above the static oil line so it won't leak until under pressure. OR a shaft seal has gone bad and scored the shaft enough to leak under pressure but not when static. The guy before me with the rock impact hole theory sound good as well. Unfortunately, you are probably going to have to disassemble the whole damn thing to find it. [:@]

 

Sam,

I can’t tell you where the leak is, but I know from experience that before you replace anything else you need to know what’s leaking. You need to get it up in the air using a jack so you can get access to the area around the belt drive sprocket. Use a couple cans of “BrakeClean” and compressed air if you have a compressor. Clean it up so that the area is completely dry and clean.

Once it is clean you need to have it leak enough so that you can tell where it is leaking but not so much that it is completely covered with oil. Run it on the jack first and look for leaks (be sure you have it tied to the jack good). If you don’t see any, take it for a short run bring it back, jack it up again and look to see where you have oil trailing from. If you have too much oil to tell, clean it up and go for a shorter run. If you don’t see oil take it and run it again. You may have to do this a couple of times to pin it down, but it will be time well spent.

When you a look at the leak, note which side of the sprocket is wet. This will help you to determine if it is coming from the transmission or the primary. (on a four speed oil from the transmission can get on either side of the sprocket, I’m not sure about yours). Often times tranny leaks are mistaken for primary leaks. So try to determine if it is indeed coming from the primary and not the transmission. Also look for leaks coming from areas other than the seals (starter, oil lines, damaged case, etc).

90 per cent of the battle is knowing where the leak is. Once you determine where it is leaking, carefully look at the components to see what the cause of the leak is.

Good Luck,
Doug

 

Everyone is giving you good ideas, and I agree with them you need to find were the oil is coming from. You said you are sure it is primary oil, so on that were is the oil leaking from, is it the input shaft seal leaking or the "O" ring were the inner primary mate's to the engine or the seal for the jack screw? Once you find out were the leak is then need to go over that area and try and figure out what is causing the leak. You may try running the level on you primary alittle lower and see if that helps. GOOD LUCK.