I recently bougt a pair of 1.00mm oversize pistons (47-108) for my carbed -01 Seadoo RX with the rotax 947/951 engine.

The paperwork that came with the pistons says that the piston to cylinder clearance spec is .007-.008", but the OEM Seadoo manual says .008" is the upper wear limit and that .0035" is the normal spec.

Is it really nessesary to have this much piston clearance when changing to SBT pistons? I was hoping to get rid of some engine rattle with a fresh top end, but with this much clearance, it fells like Im rebuilding my engine to an even worse spec than before.

Please confirm the minimum clerarance needed so I can send my cylinders of to be bored.

Thank you for a great forum!