My primay case had a major oil leak , firstly It had a low spot on the inner case lower edge ,approx .020 measured on a surface plate , filed and sanded all ok , also the sliding plate seemed to be a big source of leakage , it had already been fitted with a neoprene seal,I've added a speedy sleeveto the hub adapter to provide a smooth surface for the seal, And I wanted to provide an umbrella for the sliding seal plate ,here's the winning design ,its welded on now .I've also vented it , welded the other threaded holes from my previous failed design . Cheers .
Looks good Bigsingle
I have a similar rear cover on one of my bikes and I have found another small but annoying source of leaks is from the threaded through holes at the right side bottom of the inner cover, especially on the oil drain and oil level hole locations. Oil was migrating along the installed outer cover retaining bolts and out the inner (right) side of the inner cover.
I made 2 or 3 short 1/4-20 allen head plugs with fiber washers and installed them on the back side of the inner cover. It wasn't easy with the completely assembled primary but the plugs stopped the small leaks. It may be easier for you to come up with a more elegant solution with the cover removed.
Jim
Quote from: Jim S on 14 Oct, 2024, 15:30 Looks good Bigsingle
I have a similar rear cover on one of my bikes and I have found another small but annoying source of leaks is from the threaded through holes at the right side bottom of the inner cover, especially on the oil drain and oil level hole locations. Oil was migrating along the installed outer cover retaining bolts and out the inner (right) side of the inner cover.
I made 2 or 3 short 1/4-20 allen head plugs with fiber washers and installed them on the back side of the inner cover. It wasn't easy with the completely assembled primary but the plugs stopped the small leaks. It may be easier for you to come up with a more elegant solution with the cover removed.
Jim
I did wonder about the back of those holes ...and was going to weld them closed , but didn't, if I see that and I have enough thread, i will plug like you have done , I did counter bore the outer cover bolt holes and fitted some copper washers to them all , I rechecked my oil and have added just a little more so I could see oil flick off the chain . I will take it for a 20 mile ride this week . Cheers.