Scratches in combustion chamber

[pac00t]

Hey, I just recently took the head off to fix a valve, and while it's off I'm trying to clean it all up. I got most of the carbon out of the combustion chambers, and there's some pretty decent scratches. Polishing won't get rid of the big ones, and I was wondering if I should take dremel and see if I could gently grind them out. Would this be dumb? Would any slight variatiions in the surface hinder flow more than the scratches.

at least the cylinders look ok.

[strom]

I wouldnt worry about it too much.


LP

[TopCatGr58]

Hey Pac,

I don't know if I agree with Strom? Deep gouges in the combustion chamber might allow carbon to build up unevenly on it, and get a bit hotter than the rest of the chamber, possibly contributing to preignition (knock)!?

Some other more learned engine-ers may chime in with pros or cons about this!? I would think a light handed approach with a dremmel to smooth out the surface of the scratches without necessarily going much deeper into the head would be prudent!
T.C.

[MAXIMAN]

The bigger question is "How did those gouges get there to begin with?"

Did sonething come apart in that chamber to have caused this?

[pac00t]

I don't know how those gouges got there. They aren't too deep. I ought to post a picture. But some look like if I took a dental scraper thing to it. I think this bike has been run pretty hard 36k on it. I've been going through a number of fixes with it. The cylinder walls look nice and smooth, but the chamber looks like chunks of carbon flew off the piston and on out the valves. Not sure if carbon can do that, but these heads are soft

[mro]

but these heads are soft

Know a few mechanics that have that problem.

You do not want to remove a significant amount a of metal from one combustion chamber (several CC's worth is significant)
Will change the volume in that cylinder at "combustion" making that one cylinder weaker (by comparison) to other cylinders. Can rob a tiny bit of HP and run a tiny bit rougher.


mro

[HobbyMan]

maby a "light" hone? How was the compression before you dissasembled it. If it was low, maby new rings too.