hello everyone,
another issue has arisen, the oil level reads at the bottom of the normal mark when the engine is cold (sits in the unheated barn). the past few times i have checked it after the bike warms up and the level will be at the top mark. however now the level is at botom mark cold, and after runing for a minute, or even a longer warm up the level is at the tip 1/2 inch of the dipstick. this alarming diference makes me feel that the oil might be held up in the crankcase or something.
once agian thanks for any information!

 

Yes, that is correct. They will all do that. That is why the owner's manual sez to check the oil level, First start engine and run 20-30 seconds, Then check the level. This short run moves "excess" oil from the tiny 8oz crankcase to the oil tank, allowing you to accurately measure the level. If you check it cold without the startup 30 secs you'll always get low measures. Sounds like your's is just fine!

 

 

Let if it run and shutting it off would help a little but no enough to bring it up to the normal runnig level. I have it all apart now, adjusted the valves since it just got done with breakin. I peeked down the spark plug hole and there's oil. A healthy coat on everything. So the mysterious oil leak has been burning oil. Correct me if I'm wrong but two things could cause this-
Piston rings- (keep in mid it's a new rebuilt engine) there's no oil coming out of the crank breather hose,I pulled te hose off the engine case and no traces of oil in the hose either. so I would think this could be eliminated
Second- valve seals- when this was rebuilt the valves and head were lapped and new Moose valves seals were installed.(unless the shop forgot to do this part come to think of it).
Thanks for the input guys, none if this has been easy so thanks for the help!

 

Was the cylinder bored out or just std rings installed back in? If it was bored what clearance was allowed between the piston and the cylinder?

 

It was bored to 92.5 mm and the appropriate wiseco piston and rings were put in.

 

The critical thing even if it's been bored to 92.5mm is final fitment of the piston to cylinder clearance by honing. This is where I've seen even some good machine shops just "allow" .002 clearance between the base of the cylinder and base of the piston skirt. This is way too much as the piston to cylinder clearance should be between .0006 to .0018 max! The "wear limit" is only .0024. Ring end gap should be between .0079 to .0138. This engine is set up tight! What I'm trying to get at is if it was finish bored and honed with too much clearance,this could account for the oil in the combustion chamber from piston/ring seepage if you've ruled out new valve guide seals which should have been installed as standard proceedure on valve jobs.

 

At the machine shop where I took he ordered the piston and did the boring. He said he would check the clearance on it when he got the piston.
I have way to much money in this to have to redo it all....

 

i will give the shop a call tomorrow to see if he remembers working on my engine.
even if it were the rings wouldn't there be an issue with some gas in the oil or blowback?

 

All depend on how long you've run the engine on the new rebuild and again how much clearance was allowed.Possible the rings haven't seated yet and may do so as you put more miles on it.Plus on a new engine I would use only 0w40 and change it after 25 hrs. If it's a minor oil seepage past the rings and burning it as you drive,it would take a while to contaminate the oil with gas and you would usually smell gas on the dip stick.Plus if the seepage is low enough you may not notice any white smoke from the exhaust. At any rate there shouldn't be oil on top of the piston after a few hours driving time, only a slight amount of discoloration from a little carbon build up and heat.