Recent content by Motomike93

What do you mean by jetted carbs? Did you change the jets and if so why did you do that? Air intake or exhaust mods?

I am going to continue with doing just the top end with new cam bearings as everything else I have measured has been well within service limits. Minimal time to do the work and the cost is a head gasket, cam bearings and ring set. Worst case it doesn’t last I have another engine that didn’t...

It doesn’t look that bad but I’m going replace that roller bearing plus the ball bearing on the chain end. With the lack of upper lubrication it can’t hurt having new bearings up top.

Going through all the oil galleries to make sure everything is clear. While going through the head I noticed the only feed hole to the head is rather small. Has anyone ever increased the size of it for more oil flow? Or just stick with the roll pin in the crank TSB?

The first three photos are the camshaft of the motor with worn out rockers and camshaft. The last two are the cams of the smooth running engine. Everything else on the “low” mileage motor looks good in terms of wear except the rockers/cam which were shot. Attached is a photo of the cylinder...

Thanks for the input teazer and irk miller. Yea it is very difficult to believe even with the cylinder head lubrication issue that there would be that much cam wear. At any rate, I have decided to go forward with the "lower" mile engine and do a top end on it since the exterior of the engine is...

Hello Do The Ton members, My name is Michael and I am new to the forum however I have a project bike that I feel Do The Ton members have experience with. I have two 1980 Yamaha SR250 engines one with 20,000 miles and the other with 4970 miles. I have never used either for riding and...