sorry, but you need them. I tried to do a stingray, dosent work.
If i were you i would buy the adapters, or sell the stingray
heres a list of good bikes:
http://motorbicycling.com/f31/plug-p...hina-9686.html
And i myself have ahd 5 attemts to find a bike for my 48cc, none worked,
I also advise you not to get a bike with a fat frame, or coaster brakes, and if you can before you get a bike take off the back tire and test the sprocket. Also, bring the bracket that come on the motor mount and lay it on the frame to see if it fits.
Good Luck!