Ring gap

[la400ex]

I finally got my cylinder back and im ready to install my piston and cam. I have never done this before. What ring gap should it have and how do you do it? It shows in a manual just filing them down but I dont wanna screw it up. Thanks Ant.

[nakomis0]

ring gap....?.....

I don't recall any filing thats needed. Are you talking about where to line the gaps on the rings?

[joeroadking]

recomended ring end gap is .004 per inch of bore for top and second rings so a 400ex with aprox 3 1/2 inch bore should have .014 aprox thats how I set mine, I set just the ring in the bore and level it using the piston then measured distance with feeler gauge that how I did it . place the end of a small file in vice and file rig gap until desired gap is achieved remove any shrpe edges or burrs

[F-16Guy]

Do exactly what joeroadking said. Don't gap the oil rings (bottom), just the top two.

[nakomis0]

dang I didn't know that. I just threw my rings on, and slapped the piston in.

[la400ex]

Thanks, sounds pretty easy. I just dont have a feeler gauge that big. I bought some yesterday and they are too big to adjust my valves and too small for this.

shim stock could work in place of feelers
provided you have a supply of marked shim stock

[Predator36]

Most Wiseco rings come with the gap set well enough that they do not need any attention. Some J E pistons will need to be set. Most ROSS pistons come with to small a gap or no gap and will cause engine damage if not set properly.

[la400ex]

When I put the ring in the cylinder, the ends overlap. Im gonna have to file a pretty good bit off of them.

[joeroadking]

what kind of piston rings ?does the piston fit ok ?

[la400ex]

They are ross racing rings that came with the piston. The piston fits ok. Im gonna call around and see who can gap the rings for me. I would do it but it seems easy too screw up. My luck, i would take too much off and the gap would be too big. Then i would have more down time. Im ready to ride. Thanks, Ant.