RE: Can someone tell me why my motor went up in smoke
HPI firebolt 15t motors are cheap. Might have to drop down 2 teeth on the pinion to run a 15t motor tho.
Gearing sounds right. A 20t motor geared right can certainly run on a 2s lipo. Probly just and old motor.
An ezrun/tacon 3300-4000kv motor will work well. less than $50 on hobbyking or hobbypartz
much more power and will last longer than any brushed motor. Since you already have a brushless esc, make the motor match...otherwise, its kind of a waste.
I see used VXL, reedy and other 540 sized brushless motors on ebay for $35-$45 all the time.