When upgrading motorized bicycles, a reliable rear hub sprocket adapter is essential for aligning sprockets with common hub sizes. This guide highlights five compatible adapters, outlining fitment, components, and installation notes so riders can compare options at a glance and choose the right fit for 49cc–80cc engines.
| Product | Brand | Rear Hub Fit | Included | Notes |
|---|---|---|---|---|
| 1/1.5 Silver CNC Adapter 32T Sprocket | Simachine Store | 1 or 1.5 | Adapter, reducing gaskets, sprocket | Fits a wide range of motorized bikes |
| Sthus Silver 1 / 1.5 CNC Adapter | sthus Store | 1 or 1.5 | Adapter, reducing gaskets | Replacement parts; non-original |
| CDHPOWER Rear Hub Adapter 1.25 | CDHPOWER Store | 1.25 rear hub | 3 pcs. bolts; adapter | Designed for spoke-wheel bikes; specific sprocket compatibility noted |
| UAUS Silver 36mm CNC Adaptor | UAUS | 1.5 (approx.) | Adapter | For 66cc/80cc motors; axle diameter check advised |
| Rear Hub Adapter 1.25 CNC Fully Made | DONSP1986 Store | 1.25 rear hub | Adapter; mounting screws included | Spoke-wheel compatibility; includes screws |
The following sections provide detailed product insights, features, and installation considerations to help you pick a compatible adapter for your motorized bike setup.
1 In / 1.5 In CNC Adapter 32T Sprocket
The Simachine Store adapter supports both 1″ (25 mm) and 1.5″ (38 mm) rear hubs, making it versatile for a range of engine sizes from 49cc to 80cc. The package includes a CNC adapter, two CNC reducing gaskets, and a sprocket, enabling a straightforward upgrade path for popular spoke-wheel configurations. Installation relies on proper alignment of the rear hub to ensure the sprocket sits flush with the chain. It is suitable for 2-stroke motorized bicycles and emphasizes compatibility with common hub diameters.
Key considerations: verify your rear hub diameter before purchase; confirm compatibility with your 32T sprocket count; ensure you have or are prepared to use the included reducing gaskets to achieve a proper fit. This option is ideal for riders seeking a single kit that covers multiple hub sizes in one purchase.
Sthus Silver 1″ / 1.5″ CNC Adapter
The Sthus adapter mirrors the dual-diameter capability of 1″ or 1.5″ rear hubs with a complete kit that includes the CNC adaptor and reducing gaskets. Marketed as replacement parts and non-original, this option targets riders who want a cost-effective upgrade that preserves compatibility with 2-stroke motorized bicycles in the larger engine family. The included gaskets support precise spacing to avoid chain alignment issues.
Installation notes: check your hub size (1″ or 1.5″), confirm the sprocket bolt hole pattern aligns with your chosen sprocket, and use the provided gaskets to achieve the correct clamping torque. This adapter serves as a practical alternative when OEM parts are unavailable.
CDHPOWER Rear Hub Adapter 1.25″ With CNC Sprocket
The CDHPOWER adapter targets 1.25″ rear hub standards for spoke-wheel bikes and includes a CNC sprocket in the packaging. The product notes emphasize precise alignment with unique design features that prevent misdrilling, while clarifying compatibility constraints—specifically that it does not fit 9-hole or 6-hole sprockets. This makes it suitable for certain 66cc/80cc or similar-class engines, but buyers should confirm hub diameter and spoke-wheel compatibility before purchasing.
Important fit guidance: this adapter is intended for spoke-wheel bikes with a 1.21″ to 1.25″ hub diameter; do not rely on it for non-spoke configurations. If your project uses a 40T sprocket, ensure hole alignment with the included hardware.
UAUS Silver CNC Adaptor for 1.5 Inch 66cc / 80cc Motorized Bike
The UAUS adapter is positioned for 66 cc and 80 cc motorized bikes, with a caution to verify axle diameter prior to purchase. The package includes one adapter, and buyers must measure their rear axle accurately to determine if a reducer ring is needed when the axle measures exactly 1 inch. This helps ensure a snug, secure fit and reduces chain alignment issues during operation.
Purchase considerations: confirm your axle diameter, check compatibility with your sprocket size, and assess whether a reducer ring is required. This option is appropriate for riders who need precise dimension matching for a higher-displacement motorized setup.
Rear Hub Adapter CNC Fully Made 1.25 For 66cc/80cc
This fully CNC-made 1.25″ rear hub adapter is designed for spoke-wheel bikes and supports a range of 66cc/80cc 2-stroke engines. The kit includes mounting screws (2 x 12.9 grade and 3 x 10.9 grade) and is focused on achieving robust engagement with the hub and sprocket. It explicitly notes compatibility constraints around sprocket hole patterns, urging buyers to verify hub type and sprocket compatibility before purchase.
Practical guidance: ensure your sprocket is compatible with a 1.25″ adapter and that your wheel is a traditional spoke-wheel type. Consider the included stainless screws to secure the setup and minimize loosening from engine vibration.
Buying Guide: Key Purchase Considerations
- Hub diameter compatibility: Confirm whether your rear hub is 1, 1.25, 1.5 or another size, and check if a reducer ring is needed.
- Sprocket compatibility: Verify the number of teeth, hole pattern, and whether the adapter supports your chosen sprocket (e.g., 32T or others) without drilling or modification.
- Engine class alignment: Ensure the adapter is recommended for your engine displacement (49cc–80cc) to avoid improper chain tension or misalignment.
- Wheel type: Some adapters are designed specifically for spoke-wheel bikes; others may work with cast rims. Confirm wheel type to ensure proper mounting.
- Hardware included: Check whether mounting screws and gaskets are included and if you need to source additional fasteners or spacers.
- Installation precision: Accurate measurement of axle diameter and hub width reduces fit issues and improves safety and performance.
- Non-original vs OEM: Replacement parts may be labeled non-original; evaluate warranty, compatibility, and return options when choosing.
- Future upgrades: If you plan to upgrade to a different sprocket size or engine, consider adapters that accommodate multiple hub sizes to minimize future purchases.
In summary, selecting the right rear hub sprocket adapter involves confirming hub diameter, ensuring sprocket compatibility, and matching to your engine’s displacement. By reviewing the options above, riders can identify adapters that provide secure fits, clear installation guidance, and long-term reliability for motorized bicycles.