please note. . didn't BUY the motor to convert it (or DID he. . ) and made all the parts in a machine shop instead of purchasing them.
Lets comapre apples and apples. .
lets see. . buy a new 56cc motor. . $125??
PAY to have it machined and weight removed $75???
and add parts necessary to make it fit our planes . .$75???
and igniton $125. . .
There's 400, easy.
contact your local yokel machinist for prices for his work and for fabricating the things you need for the motor. . .You see. .. not everyone has a 56cc motor just "laying around"
Now. . granted. . this is not a bad little conversion of a weedy/chainsaw motor. But everyone wants it to be something it's not. . It's NOT a DA.

It may be a few ounces lighter. . it may be less expensive. . it does not make the same amount of power, though, at 12% larger displacement. And, most important, it does not have a warranty or free repair if you break it.
How much is a warranty and future support and repair worth? I'd say. . every penny of th price difference in the two engines.
And NO, I can't afford a new BME or DA50 .. otherwise I'd already have one (and then I could be called a liar for posting rpm figures for it)