Whatever you do, GET A ROLLER BARING CRANK.
Otherwise, you might pump too many rpms into the engine, the crank will fail, you'll throw a rod, blowing holes in the top and bottom of the case. It will burst into flames while you're doing 40mph up a hill, and shrapnel will crack your intake and dent your float bowl. By the time you jump from your moped and try to put it out, the fire will have melted the wiring, and melted/burned right up your fuel line.
It happened to me.
Check it out (see the pictures) https://www.mopedarmy.com/forums/discuss/7/154746/154746/