Motorcycle Safety & Driveability: 1970 yamaha enduro, stroke oil, stroke engine

Question
dear william,
   I was wondering if you would know what type of oil went in the right side of the 1970 enduro engine just under the kick starter.I know it is not motor oil because it is under the seat. I know my describtion of the bike is not the best but i hope you can figure it out.

thank you for your time,
charlie

Answer
Charlie,

Sorry for the delay in response, I only got the email today.

Since I don't know what model your bike is, or if it's a four-stroke or two-stroke, I can only take an educated guess as to what goes in the right side of the engine.

From your description, it sounds like you have a two-stroke engine. That would make sense, since Yamaha made a lot of two-strokes in 1970.

If that's the case, then the oil that goes in the right side of the engine is for ENGINE oil, most likely Yamalube 10W-40 oil.

The small tank under the seat is for TWO-STROKE oil, the oil that mixes with the gas to keep the piston lubricated.

So if you put "engine oil" in the tank under the seat and go ride the bike, it's probably going to smoke like crazy, then eventually the engine will seize up and it will be time for a new bike.

If you put two-stroke oil in the engine, it may run OK for a bit, but when it gets real hot, the engine will fail.

Again, not knowing EXACTLY what bike you have, it's tough to tell, but most likely the above scenario is correct.

Make sure the right oil goes in the right place.

Good luck,

Bill