Topic: Cb750 number 4 burning oil

[Tracksnblades1]

Does the slide in #4 carburetor go up and down with the other 3….?

Oooooo, I like your thinking.
You think it's sucking in oil as it can't draw air?
I will check.
I had it at 70mph on the way home while it was in this state. It felt ok, ish. It was raining, I just wanted to get home, it seemed down on power and didn't want to idle, but it didn't sound like it was running on 3.
Maybe at certain rpm it could get enough air, and not at others.

Oh, I thought #4 was dead and just blowing oil in the exhaust..

[graeme7]

Does the slide in #4 carburetor go up and down with the other 3….?

Oooooo, I like your thinking.
You think it's sucking in oil as it can't draw air?
I will check.
I had it at 70mph on the way home while it was in this state. It felt ok, ish. It was raining, I just wanted to get home, it seemed down on power and didn't want to idle, but it didn't sound like it was running on 3.
Maybe at certain rpm it could get enough air, and not at others.

Oh, I thought #4 was dead and just blowing oil in the exhaust..

4 was firing, but maybe not consistently

[ekpent]

Raw  gas from a cylinder not firing right can mix with carbon in the pipe and have a dark oil like color.

[graeme7]

Raw  gas from a cylinder not firing right can mix with carbon in the pipe and have a dark oil like color.

A little. Easy to tell the difference though!

[graeme7]

Last week, not a care in the world