Blue my bike pulls hard off the bottom,the gear I usally run is a 16/40 it will pull harder than what I need with that on small tracks, on the big tracks like 3/8 or 1/2 mile tracks I will put a 39 tooth on back and it is plenty of gear. When I took my boost bottle out my throttle responce get better, it will pull hard when I am just idling and hammer it without using my clutch.