The Heavy Hitter 420 Primary Chain Drive Conversion Kit is the highest-performance chain drive solution for Sur Ron, Segway, E Ride, Ventus, and Falcon platforms. Stock belts might survive casual riding, but when you throw real torque at them, especially with upgraded motors and controllers, they fail. Other chain kits try to solve the problem but bring excess weight, higher resistance, or rubber dampers that actually accelerate chain wear. Heavy Hitter fixes all of it.
After years of testing and breaking parts, we built the lightest 420 primary kit on the market with the least rotating mass. The setup pairs a 7075 T6 billet aluminum rear sprocket for weight savings with a nitrided 52100 tool steel front sprocket for maximum durability. A Japanese non-O-ring chain with master link keeps rolling resistance at a minimum while making swaps and maintenance simple. Unlike rubber-lined sprockets that trap dirt and mud between chain links, this kit is designed for pure efficiency and long life.
The conversion maintains OEM motor alignment and gear ratio, with precision machining that extends sprocket life and keeps performance smooth at high RPM. It’s louder than a belt — no avoiding that — but no louder than any other chain kit. And if you want to quiet it down, you can fit an O-ring chain (at the cost of some performance). From stock power setups to high-output EBMX, Sotion, or Torp builds, this kit is race-proven and built for abuse.
⚠️ Important Notice: When installing, make sure your chain tension is loose not tight! Any chain drive that you install should have loose chain tension! Please check the fitment tab for important motor info. (MORE INFO HERE)
Features
- 7075 T6 billet aluminum rear sprocket (black anodized)
- 52100 tool steel front sprocket with nitrided black surface coating
- Lightest primary kit on the market for maximum performance
- 42-link Japanese non-sealed chain with master link included
- Maintains OEM gear ratio and motor alignment
- Precision-machined for long sprocket life and smooth performance
- Best Efficiency Rated Chain Drive on The Market
Fitment
- Sur Ron LBX
- Segway X160 / X260
- E Ride Pro-S
- E Ride Pro-SS / 2.0
- Ventus ONE+
- 79Bike Falcon Pro / GT
- EBMX XLB Series Motors MUST be properly shimmed, or else you will have side wear to the sprockets!!
Important Notice: When installing, make sure your chain tension is not tight! Any chain drive that you install should have loose chain tension!