On paper, the formula looks like all engines will be equal, but in reality, when they get race prepped, the outcome is very different…
In all honesty, unless one motor is like 10hp more than another, the choice is pretty simple, buy a motor you can readily get parts for…..
I get parts for various KZ engines with no problems. I went to a local Honda shop for a piston one day….shop had to order it from a warehouse in Iowa. Now with CR125 out of production parts will get even harder to get.
I like to think of the CR125 as a ‘Johnny Cash’ engine ‘One Piece At a Time’.