Belt 729-17.5-30 Fit GY6 49cc 50cc 139QMB 139QMA Engine Long Case Go Kart ATV
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Compatible Models
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Belt 729-17.5-30 for GY6 49cc 50cc 139QMB 139QMA Engine Long Case
This belt 729-17.5-30 is a drive belt for GY6 49cc and 50cc engines, including the 139QMB and 139QMA long case variants, used in go karts and ATVs.
Overview
This belt 729-17.5-30 is a replacement drive belt for the GY6 49cc 50cc engine family, including 139QMB and 139QMA long case units. It transfers power from the engine to the CVT, enabling movement in go karts and ATVs. The belt measures 729mm in circumference and 17.5mm in width, with a 30-degree angle, matching the standard dimensions for these engines.
Built For Performance
- Constructed from durable rubber compound for long service life
- Designed to handle the torque output of GY6 49cc and 50cc engines
- Precise 17.5mm width ensures proper CVT engagement
- Reinforced tensile cords minimize stretch and slippage
- Engineered for the long case CVT housing used on 139QMB and 139QMA engines
Fits These Machines
- for GY6 139QMB engine long case go karts
- for GY6 139QMA engine long case ATVs
- for 49cc 50cc GY6 engine scooters with long case
On-The-Job Use
- Replaces worn or broken drive belts during routine CVT maintenance
- Used in go karts to transfer engine power to the rear axle
- Used in ATVs for recreational off-road riding
- Suitable for utility vehicles powered by GY6 49cc 50cc engines
Specs At A Glance
| Belt Length | 729 mm |
| Belt Width | 17.5 mm |
| Angle | 30 degrees |
| Part Number(s) | 729-17.5-30 |
Good To Know
Q: How do I know this belt fits my engine? A: This belt is specifically sized for the GY6 49cc 50cc long case engines with part numbers 139QMB and 139QMA. Confirm your engine's CVT case style and belt dimensions before installing.
Q: What happens if the belt is the wrong width? A: An incorrect width can cause poor acceleration, slippage, or premature wear. This 17.5mm width matches the OEM specification for these engines.
Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.