Bonnell 805 Parts & Upgrades: Radmoto’s Living Fitment Guide
The Bonnell 805 is building an aftermarket of its own. We’re putting the useful details in one place: drivetrain sizing, replacement brake parts, and the fitments worth knowing as more options become available. We’ll keep adding to this guide as we learn more about the platform.
The bike in this guide
Bonnell 805 RX Electric Dirt Bike
See the bike page for current pricing and availability.
View bikeLast updated: October 21, 2026.
A 520 drivetrain is the starting point
The 805 uses a 520 chain. That’s the size to start with when looking for a replacement chain and matching sprockets. A chain’s size does not tell you its required length, though: link count still needs to match the bike’s sprockets and axle adjustment.
Warp 9 lists a Bonnell 805-specific rear sprocket for the factory rear hub. The manufacturer describes it as a direct replacement without hub modifications, offered in 7075 aluminum or steel. Aluminum reduces sprocket weight; steel favors wear resistance. See Warp 9’s 805 sprocket details.
Changing tooth count changes the gearing. Going larger at the rear increases reduction and wheel torque for a given motor torque; going smaller does the reverse. Before changing sizes, check chain length and adjustment range as well as chain-guide clearance. We’ll add specific combinations here when we can document the complete setup.
Dedicated brake rotors: 240 mm front, 220 mm rear
Warp 9’s 805 range includes a 240 mm front rotor and a 220 mm rear rotor. Those are the dimensions on its dedicated Bonnell listings. Diameter alone does not establish that another bike’s rotor will fit: mounting pattern, offset and thickness matter too. Choose the 805-specific part for the correct end of the bike.
Folding levers are already on the radar
Warp 9 names the Bonnell 805 in the description for its folding brake levers. The design includes adjustable reach and a folding hinge, useful features to look at when dialing in lever position or replacing a damaged blade.
We carry the Warp 9 folding brake levers. Confirm the correct side and your existing brake assembly before ordering. Warp 9’s written description and its separate fitment selector currently show different model coverage, so contact us if you need help matching the exact lever. This supplier listing is our starting point; we’ll add an installation note when we verify a set on the bike.
What we’re checking next
We want this guide to answer the questions that come up when you actually work on an 805: replacement-chain link count, useful gearing combinations, rotor measurements, and which familiar parts genuinely cross over. We’ll add measurements, photos and installation findings as we confirm them.
Have an 805 setup you’ve already tried? Tell us what you’re running, including the part number and any spacers, adapters or other changes it needed. Those details help the next owner get it right.
Looking at the complete bike? Explore the Bonnell 805 RX at Radmoto for current options, pricing and availability.
Fitment sources: Warp 9’s Bonnell 805 range, its dedicated rear sprocket listing, and its folding lever description. Manufacturer-listed compatibility is identified above; firsthand installation findings will be added separately.