For the Alpha 40 spending the money on "Swiss bearings" is a waste of money, Jan. Just buy the Evolution bearings from Advantage RC for about $15 and the engine will be happy for years and years. This 40 was always used on Hangar 9 trainers. It will never turn serious rpms even though it is a good engine for what it is designed for- trainers.

The 46NT is a 40 that has a bored out liner, larger piston, longer rod, and a new crankshaft for the longer stroke. This is a different animal altogether.