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MxMods

Razor Mx650/Sx500/Rsf650 Motor Tensioner

Razor Mx650/Sx500/Rsf650 Motor Tensioner

$19.99 USD
$34.99 USD $19.99 USD
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Motor Tensioner for Razor MX650/MX500/SX500/Rsf650

This heavy-duty motor tensioner is precision-designed for the Razor MX650, MX500, and SX500 electric dirt rocket models. Machined from 0.125‑inch (3.2 mm) stainless steel plate, the tensioner provides a rigid mounting interface that resists bending and flexing under heavy load. It includes a spacer and one M6×20 mounting bolt to align and secure the motor at the correct height. The robust steel construction and corrosion-resistant finish ensure reliable long-term performance in rain, mud, and harsh off-road conditions. Overall, this tensioner delivers improved drivetrain stability and consistent chain/belt tension for demanding ride conditions.

Key Features

  • Model Compatibility: Direct-fit for Razor MX650, MX500, and SX500 dirt bikes (with MY1020-style motors). Mounts to the stock motor bracket without modification, ensuring perfect alignment with the rear sprocket.

  • Heavy-Gauge Steel: Fabricated from 0.125″ (3.2 mm) thick cold-rolled steel for exceptional rigidity. The thick steel plate resists flex under torque, providing the strength and reliability needed for intense off-road use.

  • Included Hardware: Supplied with a precision-machined spacer and one M6×20 mounting bolt. These hardware pieces set the motor spacing correctly and firmly clamp the motor to the tensioner, making installation straightforward.

  • Durable Construction: The tensioner’s robust steel body features a corrosion-resistant finish. It stands up to rain, mud, and the rough terrain of off-road riding, ensuring long-lasting durability.

  • Performance Reliability: By securely anchoring the motor and maintaining precise chain alignment, this tensioner minimizes chain slippage and vibration. The result is smoother power transfer and reduced drivetrain wear during aggressive acceleration or uneven terrain.

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FAQ

Why Belt Drive?

If you've spent any time on a Razor with a chain, you know the problems: chains stretch, rust, need constant lubrication, and the stock tensioner is garbage. A belt system eliminates all of that. Here's what changes when you go belt drive:

Maintenance: no more chain slop, constant lubrication, and broken links. just install and ride. with chain systems, lubrication is necessary, and gets messy.

Noise: Near-silent, sounds like a freakin' missile, no more metal on metal rattle, all you hear is pure, raw motor sound.

Power Curve: Arguably the best improvement over chain drive, the throttle feels smooth as butter, and drastically improves the smoothness of your bike, its hard to explain without feeling it, but especially with cheaper amazon/vevor controllers that feel jerky and delayed, this belt drive system is the best and cheapest upgrade to remove that issue. imagine going from a old truck to a tesla plaid.

Can i use it off road?

you are able to do some light off roading with it, but the belt conversion excels on road. thats when you can really benefit from the smoothness and lack of noise.

What parts do i need to be able to convert?

the belt drive comes with everything you need to make the switch, however, you will need the stock 79t sprocket that comes on the bike, as well as a motor mounted tensioner if you do not already have one. a welded freewheel is also recommended.