I just put a two blade prop on my alpha trainer, but it doesnt want to fit right. It is a 2 1/4 spinner but the evolution engine conversion back plate does not want to fit the spinner. If anyone has converted their trainer to a two blade prop, please provide me with some info.

I would put a new spinner and back plate assembly on the engine rather than using the old one that wont fit. I am not quite sure what the problem is, but that is what i would suggest.

I converted mine right away. Use a new backplate, the one that came with the 2 blade spinner.
Keep the flywheel on the engine, use an 11X6 prop.

Jetts

Im sorry, I should have explained it better. I meant that I took the flywheel off because it would not fit the dubro spinner. So I bought a evolution replacement prop driver but it does not fit flush with the spinner backplate. I didnt know what everyone did when they converted to a 2 blade prop. Jettstarblue, mthe flywheel will not fit with the new spinner, how did you do it.