Hi,

Good info on the chrome or Nikasil bores. If you do have to hone these type cylinders, use the finest grit stones you can and go easy. The rings for these engines are designed to work with a very smooth, almost mirror like finish. The special hone RCIGN1 is talking about is generally called a "glaze breaker", and works especially well on two stroke bores. It looks like a bunch of carbide balls on wires, sticking out from the center part that chucks into the drill.

At the Rotax engine qualification school, they taught us to heat the bore before using muriatic acid to clean seized aluminum from the bore and it does seem to work better at removing all the aluminum than the old way of just applying it cold. I don't know how this might work on a chrome or Nikasil bore however, so try it at your own risk.

Thanks,
AV8TOR