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Motorcycle Repair/inner primary fluid leak - S&S Evo


QUESTION: Mike - have an 88CI Evo S&S, belt drive. I have a leak that accumulates inside the outer primary cover. What possible seals would need to be replaced that will correct this issue? if I take off the inner drive primary, which seals need to be replaced? I understand that the compensating sprocket is left hand thread. is this correct? How do I know if this is trans fluid or oil?

thanks much

ANSWER: First you would have to find the leak. I would clean the bike really well and let it dry. You can then spray some deodorant that has baby powder in it over the areas that you think you have a leak. Start the bike and where the leak is the powder will turn black. You can also purchase some color to put in the oil. When it leaks you can see that color it is and then you know which oil is leaking.
If its the inner primary and you remove it you need to replace all the seals, not just the one that is leaking. You don't want to put old seals back in. The compensating sprocket is right handed thread. The clutch hub nut is left handed thread.
Good luck and happy riding

---------- FOLLOW-UP ----------

QUESTION: Mike - upon further research and to provide more information..

- the engine has no leaks from the rocker box covers, gear case, drain plug, hoses, compensating sprocket or elsewhere
- inner primary was removed by a shop and the shift shaft seal, and transmission shaft seal were replaced (not leaking from here)

It seems the leak is from the transmission breathing tube and in the middle of the clutch assembly. I know there is a rod that the clutch uses to manipulate the clutch plates. When I have the primary cover off and run the bike, the momentum of the clutch moving sprays a slight trail on the floor. There is no trail on the inner primary cover or seeping.

Any advice greatly appreciated, again....

The rod you are referring to in the clutch is enclosed in the primary, so It cant leak to the outside from there. You can check the breather tube by connecting another tube and run it higher than the tube that is there and then run the bike and check for a leak.

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Mike Wells


PLEASE READ BEFORE ASKING A QUESTION!!! I CAN ONLY ANSWER QUESTIONS ABOUT HARLEYS !!! I DONT KNOW ANYTHING ABOUT OTHER MODELS!!! IF YOU ASK A QUESTION ABOUT A NON HARLEY BIKE IT WILL GET REJECTED!!!I have a Harley only shop with 30 years experience located in Ohio. We specialize in complete and total repair, restoration, hi-performance, and custom bike building. I can work on Flat Heads to Twin Cams. Please, dont ask how much somthing is going to cost to fix. Labor prices differ all over te country as well as shop to shop!


If its broke on a harley we can repair it. We do complete restoration from the frame up, engine and trans rebuilding, remapping and custom bike building

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