[Tommy Foltz]

New to the forum. I have an 85 Yamaha Maxim xj700. I had gotten into a wreck with it months ago and rebuilt it. Got everything the way I wanted it. changed spark plugs. Ran fine for three days but then started to miss in the second and third cylinder. Changed spark plugs back to originals and third cylinder fires now but second cylinder won't. All spark plugs had a spark when I tested them out of the motor hooked up to the coils. But second cylinder just won't fire. Also just for something to do, I tested compression and according to the compression tester I bought, all cylinders only make 60-70 psi. Any ideas?

 

[Dodsfall]

Try doing the compression test with the throttle held all the way open and see if that makes a difference.

Also try the test with a little oil in each cylinder. A teaspoon will do.

Any changes in pressure may let you know where the problem is.