FREE to anybody who wants to pay the postage. I bought rings and they sent me piston kits. I broke a ring so ordered ring set again, and again they sent piston kits. They have pins and circlips with them, just no rings. All eight of them.
Some things never change,,I needed one cbr piston, & spent days haggling, eventually got one for $26,,a full set arrived, complete with rings,pins & clips, so I still have 3/4 of a set left over,,,
I didnt get the micrometer out but just a visual Chinese Charlie on top 3LN below Maybe one day the ultimate test will be down the 1/8th mile , as I want to rebuild some motors when I have a real workshop thanx @Murdo
it's pretty common. Honda has them too. It starts with valves having pocket to save weight. Then the little bumps on pistons is to increase compression due to extra volume created by pockets in valves.
Thanks Danno, but the reason I was curious is because ZXR250 engines don't have domed valves, but some (potential) spaz decided to fit them to a ZXR head and the piston tops have faint witness marks where the two have decided to get personal. I have never run this engine, but the PO said it had great compression...surprise surprise. I will have to pull this head off and maybe replace those valves with standard ZXR units. I'll measure the domed valves against the normal ZXR units and report back on weight, length etc. They might actually work in the ZXR and this engine might have had a hard high-revving life before I purchased it.
