You can depend on Harley Evo's to leak oil if you own them long enough, but since we installed the "Oil Fix" from Hayden enterprises, Our Evo does not leak oil.

The motorcycle parts "Fix" kit consists of base gaskets and two-brass oil "jets". The oil "jets" are placed in the crankcase oil return holes and the cylinder oil return holes. The "jet" acts as a seal between the cylinder and crankcase return passages and forces the return holes to line up and seal properly.

Our 1993 H-D FXR has had a persistent leak from the front left side since we acquired it. We've tried all the standard fixes, Lapping the cylinder bases, rubber / metal gaskets, metal band gaskets and rubber coated gaskets. The last time we tried the James metal base gaskets and it sealed up briefly before leaking as bad or worse than ever.

This Harley Davidson motorcycle sees a lot of hard miles and testing of products. We put up with the leak until we decided to do a top end refresh. This time, we decided to fix the leak for good.

When we tore the FXR motorcycle down, we found the oil leaking from the return hole into the base gasket and out. We could see the trail of oil and found the rear return leaking a small amount also. We decided the FXR was a good candidate for the "Oil Fix" from Hayden enterprises.

In addition to the "Fix" we used the new style OEM H-D base gasket motorcycle parts and a product called Honda Bond. It is the same as Yamaha-Bond and Hylomar. We lapped the bases with the Trock tools cylinder base hone and cleaned the cylinders up to a .010 over bore. After prepping the cylinders, we turned our attention to the crankcase. We had removed the pistons to change them to .010 and now we removed the cylinder base studs. We did this to be able to check the crankcase for true and clean up any burrs or rough edges. There are a couple of ways to do this. You can use an extra fine flat file and carefully, very lightly run it across the surface looking for high spots. An easier way is to paint the gasket surface with black spray paint and then use a flat sanding block or extra fine file to determine high spots. Either way, use extreme caution and work slowly! A slip here or a nick there can turn you crankcases into $900.00 piles of junk. After cleaning up the crankcase surfaces, we installed Kibblewhite cylinder studs. These studs are 3/8? grade 8 and hardened to prevent twist and deflection. We used pipe sealant on the threads to make sure no oil could weep out of the cases up the threads.

We carefully installed the oil "jets" for the Hayden products "Oil Fix" kit, following the instructions and held them in place with some Honda-bond. Use extreme caution while installing the "jets"! You don't want to drop them into the crankcase! The "jets" are made from brass and non-magnetic. After installing the "jets", we applied a thin layer of Honda-bond to the crank case gasket surface and installed the new style OEM Harley Davidson base gaskets. Then, we applied a coat of Honda-bond to the top of the base gaskets. We waited the recommended 10 minutes to allow the Honda-bond to set up properly. We installed the cylinders and used spacers on the heat bolts to evenly torque the cylinders down so they were flush to the crankcase. This is an important step! The Hayden "fix" and "jets" must be seated into the cylinders in order to get a seal. It prevents damage to the Harley's gaskets if you seat the cylinders prior to installing the heads. We use 5/8' PVC about 2' long to slide over the head bolts.

The rest of the reassembly is standard procedure. We always use the recommended torque procedure on the head bolts. This is an important step and needs to be done correctly. We use a light oil to lubricate the threads and the shoulder of the bolt to reduce friction. Do not assemble these dry as the torque will be incorrect.

Since we installed the "Oil Fix" Our Harley Evo doesn't leak oil and is clean as a whistle.

 

where did you get this?

 

This is old post but answer is still the same...
http://www.haydensm6.com/tof_single.htm

 

My 1996 Fb EVO been around awhile still has never leaked a drop
Stock.

 

Not to condradict the OP, but "our fix" is to establish a precision machined gasket surface on the cylinder base, in a dedicated fixture in a lathe, then the use of a Cometic EST base gasket, and naturally, loaded, with the correct torque via the cylinder head bolts.
They wil not/do not leak.
Scott