Introducing the new and improved 2.1 Edition of our most popular product the Razor Ultimate Kit! Get EMX performance with your Razor MX500 or MX650 without any of the hassle. With this kit you will get everything you need to convert your razor into a brushless dirt slinging beast. delivering a true 5000 watts (with room to grow), you won't be left wanting for more. Pre wired, pre shaved, pre tuned. All that is left to do is bolt it in! This kit is designed to fit in the stock razor chassis with minimal to zero modifications. Our extensive Research and Development lead us to the absolute maximum achievable performance for the razor platform in off road situations. Taking our EMX formula and applying it to the razor platform yielded astonishingly good results at a very reasonable price point. We tested and tuned in the most rigorous conditions and demanding terrains to find the best blend of characteristics that a motocross bike should have on a platform of this nature. Our setups are guaranteed to deliver the highest performance of any kit available by flowing an astonishing 200 phase amps to the motor. Having two usable power modes allows you to tame the beast and save battery with eco. (this feature is unique to our kits) Don’t get left in the dust with other kits that have poor performance, poor throttle response and poor reliability. Say NO to toy like feel and bad habit forming behaviors. Say YES to a true mini Motocross feel and performance. The 2.1 Version of the kit now features an Exclusive and Improved version of the MY1020 motor which we are simply calling the MY1020+. We worked closely with Kunray to improve the MY1020 without breaking the bank and were able to add 50% larger phase wires over other versions and larger copper lugs to help carry that big power for longer and with fewer losses. Combined with this is a hefty 82mm rotor & high torque winding configuration; the MY1020+ is the best MY1020 motor ever produced. It also features an internal temperature sensor that will help prevent damage to the motor that occurs from overheating. But that's not all! We have also worked with Kelly Controllers to create the Model Z and Model Y Versions of the KVD7212NX which we are simply calling... KVD7212NX +... naturally! This version of the controller is an Electro & Company Exclusive and features our EMX custom firmware and a greatly improved heatsink design which increases the continuous current carrying capabilities and allows you to push the limits longer and harder than ever before! It also communicates with our MY1020+ temperature sensor to get real time temperature data and cut power if critical temps are reached; a never before seen feature we are happy to bring to the razor community. Kit Includes E&C MY1020+ v2.1 Motor by Kunray 200 phase amp Model Y Kelly Controller with E&C Exclusive Heat Sink Ultimate Razor Heat Sink EMX lite Throttle with eco mode switch Handlebar mounted power switch or Key switch Volt Meter MX Grips Wire Harness Battery Leads EMX Pre Tune Service OEM Charge Port Adapter (if the battery is selected) Compatibility Razor MX500 Razor MX650 Razor SX500 Razor RSF650 Otherwise universal with typical fabrication GEARING 1:8 to 1:6.5 Ratio Recommended for 10 inch rear wheel only.  1:9.6 to 1:7.8 Ratio Recommended for 12 inch rear wheel only.  1:11.52 to 1:9.36 Ratio Recommended for 14 inch rear wheel (not recommended) The motor comes with 11t installed, if you would like you purchase additional sprockets you can find them in our Accessories section. Recommended Accessories Complete Hydraulic Break Kit Ultralight T8F Chain Kit Forks  Rear shock(SX, MX, RSF) Extensions Battery Info 52v 20ah Top speed 25+mph (35+ with gearing) Ride Time: 1-2 Hours wheels rolling on average 4a charger 72v 30ah Top speed 30+mph (40+ with gearing) Ride Time: 2-4 Hours wheels rolling on average 5a charger 76v 20ah Top speed 32+mph (45+ with gearing) Ride Time: 1.5-3 Hours wheels rolling on average 5a charger 76v 24ah  Top speed 32+ (45+ with gearing) Ride Time: 2-4 Hours wheels rolling on average 5a charger Warning! Lithium 48v, 90A, or higher is required! 5000w output is based on 72v. The included Batteries are NOT waterproof!