Q2: Will this fit on a mongoose exhibit 29 in mtb bike?
A2: Yes, can fit on most of the hardtail's mtb.
Q3:When you say that there is a speed limit at 25km/h, is it optional? Can we remove this limit easily?
A3:Yes, you can easily adjust the value in the display.
Q4:Can this motor be installed without the thumb throttle and the brake stop in a pure pedal assist mode?
A4:Yes, you can use it without thumb throttle installed, while the brake stop is necessary for security purpose.
Q5:Does this motor have Special chainwheel?
A5: Yes, it has 38T, 44T and 52T. The regular one is 42T gear.