cadys are hardly motobecanes.. they were sold at canadian tire in the 70's = garbage. i've seen enough cadys to know they arent worth my time... or anyones for that matter. your better off kitting your schwinn 21 speed.
the motor is pretty retarded with the stator slammed behind the clutch. and the tiiiiny intake wraps around from the front. might be nice if a av7 would fit on it.
if you bought it for 50 and it runs alright, you should honestly sell it for atleast 200 and make a sick profit off of it.