Originally Posted by
mjealey
Tried 3 pipes = OFNA 086, Nova 9886, Brand new never run OS 2090. Pipes are fine as I clean them and like I said I can throw any of the 3 OS .19, OS .21, CRE P5 and it is fine. I actually have 2 MBX6r's. 1 for practice, 1 for races and it does it in both and the other 3 engines will run for 2 hours straight. Tanks, lines are new.
And I actually completely tore down and cleaned the engine to put in front bearing before this weekend. Completely cleaned with no oily residue, assembled using Nova 1n2 oil.......
I have had engine modders, dealers in the south take a look at it and tune it at the track and some thing....
We have to be missing something simple right in front of my eyes..... I WILL find it. These engines are just pretty simple in the grand scheme of things hard to believe I am missing it, but I am.
You sure you have good pinch? Like some have suggested, it may be a heat problem. Check for sleeve roundness when you have the piston in it. With just the piston and sleeve, slide it up and down and see how far the piston goes up the sleeve and report back.
If nobody can tune the engine, you have an issue with that engine. Maybe send it back to Novarossi and see if they can replace it? (make sure you have a c6tgc or c5tgc plug in there when you do send it back
)
Check the rear bearing. Does the inner race feel tight or is there some play? Rear bearing should be tight, if not, it needs to be replaced and thats likely your problem, if its loose.