Best Rear Sprocket for Motorized Bicycle: Top Picks for 49cc–80cc Builds 2026
Answering the question for riders seeking an upgrade or replacement rear sprocket for a motorized bicycle, these selections balance compatibility, ease of installation, and durability. The top picks cover common hub sizes and chain configurations, helping buyers choose based on engine size and mounting options. Ideal buyers include DIY builders upgrading to more teeth for highway cruising, riders restoring older builds, and enthusiasts seeking a robust CNC or plated sprocket for daily use.
Summary of chosen products
| Product | Key Fit | Teeth | Notes |
|---|---|---|---|
| Simachine 32T CNC Adapter Sprocket (1″/1.5″ hubs) | 1″ or 1.5″ rear hub | 32 | Versatile adapter with gasket set; suitable for 49cc–80cc engines |
| jtfrkope 9 Hole Mount Kit with 44T Sprocket | Rear sprocket mounting pads kits | 44 | Includes backing plates and washers; fits multiple CNC hole patterns |
| sthus 32T Chain Wheel Sprocket | 49cc–80cc bikes | 32 | Simple choice for common rear sprocket replacement |
| CDHPOWER 32T Multifunction Sprocket | 9/6/3 hole compatibility | 32 | Composite hole patterns; works with 415 chains |
| UAUS 44T 1.5″ CNC Adapter Sprocket | 1″/1.5″ rear hub | 44 | Aircraft-grade aluminum adapter for durability and corrosion resistance |
The table above highlights the most versatile, widely compatible rear sprockets for motorized bicycles. Each product is evaluated for fitment, typical engine sizes, and practical limitations to help you pick the best option for your build.
Simachine 32T CNC Adapter Sprocket
Brand: Simachine. Fitment covers 1″ (25 mm) or 1.5″ (38 mm) rear hubs for 49cc–80cc two-stroke motorized bicycles. Package includes: 1 CNC adapter, 2 reducing gaskets, and 1 sprocket. The design emphasizes compatibility across common hub sizes, making it a flexible choice for riders who may switch engines or hub configurations. Best for builders seeking a single sprocket that fits multiple hub diameters. Caution: Verify detailed dimensions in product images before ordering to ensure a perfect fit for your hub.
jtfrkope 9 Hole Mount Kit With 44T
Brand: jtfrkope. Fitment includes 49cc, 66cc, 80cc, and 100cc motorized bicycles. Includes: 1 rear sprocket, 3 backing plates, and 2 reinforced rubber washers. Designed for mounting pads or CNC 3-hole sprockets, with relevance for rear hub disc brake compatibility. Best for riders upgrading from smaller sprockets who want a larger 44T for better top-end speed. Caution: This kit relies on compatible mounting pads; verify whether your frame uses 9-hole or CNC 3-hole patterns.
sthus 32T Chain Wheel Sprocket
Brand: sthus. Fits 49cc, 50cc, 66cc, and 80cc motorized bicycles. Includes one sprocket and notes compatibility with rear sprocket mounting pads kits (9-hole). Best for straightforward replacement when a 32T is sufficient for city commuting and modest climbs. Limitation: Doesn’t explicitly include mounting hardware or adapters; check your current setup for necessary pads or adapters.
CDHPOWER 32T Multifunction Sprocket
Brand: CDHPOWER. Features a 32-tooth sprocket with 9-hole, 6-hole, and 3-hole compatibility. Center hole diameter is 37 mm, designed to work with both #415 chain and #415H chain and aligns well with wheel bolts in a 9-bolt pattern. Best for riders who want a versatile sprocket that can fit multiple chain types and mounting schemes. Caution: Confirm your chain type (415 vs 415H) to ensure compatibility with the sprocket’s hole pattern.
UAUS 44T 1.5″ CNC Adapter Sprocket
Brand: JRL. Designed for 1″ (25 mm) or 1.5″ (38 mm) rear hubs on 49cc–80cc two-stroke motorized bicycles. Includes: 1 sprocket and 1 CNC adapter. Adapter is crafted from aircraft-grade aluminum for durability and corrosion resistance, offering long service life. Best for riders prioritizing lightweight, durable components and a strong adapter. Caution: Confirm hub diameter compatibility with your frame before purchase to avoid installation issues.
jtfrkope 9 Hole Mount Kit With 35T Sprocket
Brand: jtfrkope. Fits 49cc, 50cc, 66cc, and 80cc motorized bicycles. Includes: 3 backing plates, 2 reinforced rubber washers, and 1 sprocket. Compatible with rear sprocket mounting pads and CNC 3-hole sprockets; also usable with rear hub disc brake ball bearings. Best for builders upgrading from smaller gearing where a 35T improves torque delivery. Caution: The 9-hole pattern requires matching hub hardware; verify alignment with your frame’s mounting pads.
Buying Guide
What should you check before buying a rear sprocket for a motorized bicycle?
- Hub compatibility: Confirm whether your rear hub is 1″ or 1.5″ and whether your mounting pads or CNC patterns align with the sprocket’s hole design.
- Chain type and pitch: Ensure the sprocket matches your chain size (commonly 415 or 415H) to prevent premature wear or binding.
- Gear ratio needs: More teeth offer higher top speed at the cost of torque; fewer teeth improve torque for hills and starts.
- Durability and material: CNC-machined aluminum adapters are lightweight and corrosion-resistant; consider steel or coated options for heavy use.
- Installation hardware: Some packages include backing plates, gaskets, or washers. Confirm you have all necessary mounting hardware.
What configuration should I choose for different riding goals?
- Urban commuting with frequent stops: Prefer sprockets in the 32T range for balanced torque and acceleration.
- Hilly terrain or heavier riders: Consider 35T–44T sprockets to improve top-end performance without sacrificing too much torque.
- Wheel compatibility concerns: If you have a CNC 9-hole pattern, pick a sprocket that explicitly states 9-hole compatibility.
FAQs
- What is the benefit of a CNC adapter sprocket? It allows compatibility with multiple hub sizes and simplifies installation across different engine configurations.
- Do I need to replace the sprocket bolts or studs? Usually not, but some kits require backing plates or washers; check the product details.
- Can I use a larger sprocket on an 80cc engine? Yes, but expect changes in acceleration and torque, and ensure frame and chain clearance remain safe.
- Is 415 vs 415H chain important? Yes; matching chain type to the sprocket ensures proper engagement and longevity.
- Are these sprockets compatible with electric motorized bikes? Most are designed for petrol two-stroke engines and may require alternate mounting hardware; verify specifications before mixing systems.