I have it on my 20in bmx bike and the 9t/32t setup does 10mph then the provided 16t freewheel sprocket does 16mph as a 16t/32t setup. sadly the 16t freewheel exploded on mine so had to get another, if this were on a 16in bike it'd have the feeling of more torque than what it does now which is good but will lower the top speed to approximately 6-12mph for max speed and not the 19 it was advertised for. For at least 20in bikes id recommended going with a 28 or 25t rear sprocket and at least a 42/16t for the pedals, if you can manage more peddling power then I'd go a 48-54t front and 16t rear sprocket setup for the peddles. iv done 2 small trips a 8 mile and 10 mile and done 2 larger ones on one 36v 7.6ah battery and got it up to 16 and 17 miles of range. wish the controller came with a xt60 adapter but I made my own. besides the lack of speed and the sprocket falling apart this has been the most fun I've had on a bike since childhood, sadly went on sale just after I purchased it but even not on sale was well worth the buy. gonna try a 48v 20a(stock is 36v 25a) controller and see if that will help with speed as my motor runs cool even after hitting all the hills in my area all in one go as a stress test.

Me vino el acelerador golpeado y casi todas las piezas arañadas y poca potencia