ORIGINAL: jeffie8696
OK I have seen all aluminum alloys in the smaller engines rods that routinely turn up over 15,000. So a .15 size engine with a big togh all alloy rod would be a good choice in what material? And what about a .40 running upwards of 15,000? Hopefully it is moot since I have found out I can buy inexpensive replacement rods for the Norvels that seem to have really weak rods.
Rpm range related to material are depending on bearing load. If the engine are a powerful hi reving engine, the aluminium con rod without bronze bearing will not last long time..
The engine used to run in moderate rpm and less load on bearing works well with con rod made of aluminium.