If you want a conversion engine there are plenty to pick from made in China. Most need some good made american bearings...ect. Maybe a good hub...not a cast one....some have broke that had thin walls. Then there is the "put it together engine"....you do the assembly. On some you may want to replace the ignition to a RCxcel or CH unit. Not all bad if you want to learn how they tick! Capt,n

And then again, they may tick only once

That is kinda true alright...some guys got lucky and got a fairly good one ore had the right skills to fix them engines. At least the kit ones have all the parts in one pile. Yos do not need to look forthe partson what needs redone! Capt,n
<hr />I think a lot of these engines would run better with a Frank Bowman ring. On small bore engines...Frank makes the best rings &amp; he has many sizes in stock! Capt,n

CRRC 40 kit engine is a good learning tool. It makes pretty good engine too. I used one on a 1/4 scale Nosen Aeronca champ. It is very reliable an pleanty powerfull. It is a lot of engine for $190.