I Personally would stay away from this engine, as it is hit or miss... I purchased 3 of these engines, two .46 and one .53.. one of the .46s is a good engine, and the other I took apart to become a relatively inexpensive guinea pig for me to see what I could mess up with a moto tool.. (haven't done anything to it yet) the .56 on the other hand, fresh out of the box felt like there was sand in the cylinder, not smooth at all scratchy feeling.. couldn't get it to run very well at all.. it's in my junk engine drawer..

there is even a forum specifically for the Aviastar .46, and even there the reviews are hit or miss.

so to summarize, out of the three aviastar engines I purchased, I wound up with, one great one, one turd, and one Guinea pig...

Craig.