ONYX RCR 72V Rear Wheel Hub Motor Assembly

Keep your ONYX RCR 72V running strong with a complete rear wheel hub motor assembly. Choose the setup that matches your riding style: the proven stock 4T for torque-focused performance, or the wider 3.5T for higher top speed potential and a more aggressive rear tire setup.

Variant: 4T Rear Wheel Hub Motor Assembly (1.6" x 17")

The original, torque-forward 72V rear hub motor assembly. This is the traditional ONYX RCR 72V spec that delivers the familiar low-end pull, responsive takeoff, and balanced everyday performance. Best choice if you want stock feel, strong acceleration, and maximum compatibility with standard rear tire sizing.

Best for: stock performance, torque, everyday riding, OEM replacement.

Variant: 3.5T Rear Wheel Hub Motor Assembly (2.5" x 17")

A higher-speed rear hub motor assembly paired with a wider 2.5-inch rim. Compared to the 4T, the 3.5T is designed to prioritize top-end speed and can add roughly 10–15 mph of additional top speed potential depending on your setup. With a stock battery and controller, expect more speed with less low-end torque, but you can recover some acceleration by adjusting your controller settings (for example, acceleration timing and power output limits within safe operating ranges). The wider rim also supports a wider rear tire for a more planted look and feel, including up to a 4-inch tire fitment depending on tire model and clearance.

Best for: higher top speed, wider tire look, riders willing to tune settings for the best balance.

Quick decision guide

• Choose 4T (1.6" rim) if you want the stock 72V feel with strong torque and acceleration.

• Choose 3.5T (2.5" rim) if you want more top speed potential and a wider rear tire setup, and you’re comfortable with light tuning to regain some torque.