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Razor RSF 650 Sport Bike 40+ mph

Hey guys, I recently purchased a Razor RSF650, which is pretty much a MX650. I just need help gathering the correct parts list to get get to 40+mph. I know if I want to get the 1000 Watt motor it will require welding.  If someone can help me with a parts list it will be extremely helpful. Please and thank you.

A 1000 Watt motor should be good for speeds up to around 26 mph however for top speeds over 40 mph a considerably more powerful motor would be needed. One of our forum members has installed an 1800 Watt motor on his MX650 dirt bike and geared it for a 31 MPH top speed which it reached with no problem. I recommend looking at his topic at this link:

I ran a calculation which shows that the top speed with an 1800 Watt motor is around 33 MPH.

To obtain a top speed over 40 MPH our calculator shows that two 1800 Watt motors would be needed.

The reason that the top speed MPH is not equally proportionate to the motor Watts rating is due to drag, which is also called air resistance. The amount of resistance that air imparts on object going through it increases exponentially as the speed of the object increases. So the amount of power needed to go 43 MPH is twice as much as is needed to go 33 MPH.

The motor power calculator shown above plus many other helpful calculators and charts can be found on our Modification and Custom Project Help page

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