The Project Pad

So I got some bore gauges, I Had the 7a honed and the shop noticed a substantial "wear ridge" at the top of the bore above the rings.
I measured the middle of bore: 82.56mm
And at the top of the bore on the ridge itself: 82.51mm
So a difference of 0.05mm, maybe a little less..
I didn't measure directly under the ridge, it might be a little larger that the middle of the bore
What is the max tolerance for wear?

My MC had the same "ridge". I did nothing about it except use some scotchbrite on it to take away the shine. Have had no problems at all with it.

DE80q wrote:My MC had the same "ridge". I did nothing about it except use some scotchbrite on it to take away the shine. Have had no problems at all with it.

Cool thanks.

Does anybody have the specs for max wear dia. of the cyl?

The way i learned it you have to measure piston to wall clearance via the skirt using a feeler gauge (individual long type) for each cyl matched to piston to make it perfect. Also diff types of aftermarket pistons may need diff clearances. If i remember right when doing cast mc pistons, wear limit was 0.003", no clue on forged and diff alloys.