cylinder oil leak...is this normal?

[ShanMan]

on the left side, at the base of the cylinder where it mates to the lower case, I get a minor yet continuous oil leak. I am afraid to try and torque the cylinder hold down bolts any further for fear that I could strip out or crack the lower case. Any of you guys have this happen to you? The p.o. of the bike says it's pretty normal for the 500, but that I should watch it to see if it gets worse over time. He says it might be time for a seal and gasket change if it gets worse, despite the fact that the motor runs like a scaulded dog. TIA!  

[djcheez]

i dont know if it is normal  on a 500 but any other bike i would assumethe base gasket is going bad. i would just take the time and replace to ensure nothing bad happens. you dont want it to get worse as yer riding and have it suck in a bunch of air and then seize. that would be much more expensive to do than a new gasket, maybe some rings and a hone. just my .02

[gowen]

I would really be careful about tightning the base past specs, due to the fact that when the cylinder gets hot the metal expands and it could burst your studs or break your cylinder. It costs maybe $12 or less for the base gasket and it isn't that hard to replace. The truth is, I would get a Cometic kit, as I've found they last longer than OEM. It costs around $30 for the entire top-end kit. But, I would retorque your cylinder back to specs  (25ft lbs) and if it still leaks, your base gasket has a tear in it, normally from viboration. But, your cases or jug could be warped, but that isn't normally an issue, I doubt it. Anyway, I doubt it will hurt too much to leave it as-is, but, I would fix the nut issue, and you will more than likely, after awhile, notice your base gasket to show a bit more, or it will disapear.. normally just make it's way somewhere..

[Rick]

You might try one of the base gaskets for a newer KX500, as they are rubber coated metal.  The factory race mechanics reuse these several times before replacing, and have indicated they can be reused up to 5 times without any concern.  I usually keep my bikes only 2 years, so perform 4-5 top ends, and have never had to purchase a new base gasket.  Also, with metal, no risk of tearing.

Rick

[ShanMan]

Thanks for the replies guys. I think I will shoot for a new gasket...the rubberized metal one sounds like a winner!