I've used worse, a lot worse, just smooth the score over with a bit of wet n dry. It's below the transfers so you shouldn't lose too much compression.
First thing I'd do though is look for what caused it???
It was stripped off another engine, piston had tried to hole, but the top and one side had broke off which caused the score I guess, should I use the piston rings from the piston for my new piston or just get new ones?
dude thats got loads of use left it, they are pretty robust though the pistons i find crack under the ring piece lands, just polish out the rough edges of the score then stick her back together :fb:
im just collecting all the bits i need to build my malossi 221 monster of a machine, slow progress, but im getting there, just need advice on gearing now as im running an over sized tyre on the back and so need to up gear it,
going to keep the cosa clutch though, buying a milled out basket for it as i know cosas are crap for handling the power im looking for