when i pulled my head of my mini i found that pistons number 1 and 4 were covered in carbon.
how do i remove this without cauzing any damage.
is there a special way.

thanx JIM

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(60 hp @ 5700 RPM) in my old mini.

wire wheel on a drill?

I dont think you should be going anywhere near your pistons with a wire brush (its for the head).

I cranked up the two pistons to the top placed a vacume hose next to the one i was cleaning to suck up all loose carbon preventig it from falling bw the piston and the wall and scraped the carbon off slowly with a plastic spatula (i'd use anything as long as its softer than the aluminium so that you dont scratch the pistons). Then polish it all with a metal polish.

I'd leave it there, particularly if the motor's done a lot of mileage.
That ring of carbon around the edge of the piston helps ring sealing- sometimes if you remove it all, the motor will burn some oil for a bit- until there's carbon on it again..

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Havent they been debating for 30 years about the benefits of a carbon ring in reducing oil consumption and still there's no concensus?

Maybe- but last time I took it all off the oil use went up for a bit...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.