Hello! I recently purchased my son his first electric bike, a Razor MX650! Right off the bat, I would want to upgrade the highest top speed possible while still being able to go up slight hills. What would you guys recommend? I would prefer not to cut the frame. Whats the best motor I can swap in that requires little to no fabrication? If you could link me all parts needed for the swap that would be greatly appreciated! looking for 25-30+ speeds. I also weigh 220 LBs and would like to ride it on occasions and go over 25, so please take that into account, Thank you!
Would also like to add ; Cutting the frame/body is not completely out of the question, But would like to explore all other options before. Would this setup work with the MX650? I know I Would have to cut but im just curious as to what else I would need to make this work, Thanks!
We carry a couple of kits that will modify the MX650 for a top speed of around 31 MPH and still have hill climbing power. These kits do not require cutting the frame other than cutting off one small metal tab that is in the way of the new motor's power cord.
Here are links to these kits:
Please let us know if you have any questions.
A fourth battery could be added to the original three batteries to lower the cost of the battery pack, however, we usually do not recommend mixing different brands and ages of batteries together into a single battery pack because the different brands may recharge and discharge at different levels and become unbalanced over time which leads to overcharging and undercharging of the individual batteries which lowers lifespan of the battery pack. This would be one way to keep the initial cost down though. We sell our MX650 kits without battery packs at these links:
Razor only sells complete MX650 battery packs made of three batteries with the wiring harness soldered to the batteries, and they do not sell individual batteries. If you get the battery manufacturer's name and the model number off the side of one of the batteries then maybe an identical battery could be found online though.
One of our customers who installed our 48 Volt 1600 Watt kit onto his kids MX650 clocked the bike at 31 MPH on flat ground using the GPS on his iPhone. On flat ground, the rider's weight barely affects the top speed and only really affects the acceleration time that it takes to get up to top speed.