I don’t want to pay $80 and the 49 cc plates have holes too close to the 79cc holes so it can’t be drilled. I can’t weld my own so I’m not sure what to do
If your frame is steel, welding a motor mount plate is really the best way to go.
Much stronger way to not only attach the engine, but it ties together and strengthens the frame as well so you are less likely to crack the seat post or down tube.
The Honda GX120 small gas engine on sale with free shipping. This GX120UT3-QX2 is a 118cc 3.5HP motor for go karts, mini bikes and various uses. Buy online today with quick shipping! This engine is a 3 by 4th inch diameter, and 3 by 16 inch keyway horizontal shaft.
First picture angle iron/ bed frame and muffler clamps like Aleman suggested.
Second picture is a piece aluminum T a few foot peg clamps and a cut off wheel.