SEHNSUCHT GY6 50cc Clutch & Variator Kit - 139QMB Complete Assembly with 669 Belt, 16×13mm Rollers

If your GY6 50cc scooter or ATV is showing slipping, sluggish acceleration, or uneven engagement, this SEHNSUCHT Fit for Gy6 50cc Clutch Assembly Kit provides the mechanical components needed to restore reliable power transfer. Designed to match the dimensions and spline count of common 139QMB engines, the kit combines an iron/aluminum clutch drum and variator assembly with a 669 drive belt so you can replace all wear items at once.

How will this kit affect acceleration and throttle response?

The variator and clutch are the primary components that control gear ratios and engagement timing on a CVT-equipped GY6 50cc. Installing fresh rollers, a properly sized belt, and a correctly matching clutch drum reduces slippage and restores the intended RPM-to-speed relationship for crisper pickup.

• Includes variator assembly with rollers sized 16×13mm for consistent ramping.
• Comes with a 669x18.1 belt to fit the factory pulley spacing and tension profile.
• New centrifugal clutch pad assembly ensures predictable engagement under load.
• Reduces power loss from worn friction surfaces for improved throttle feel.

What exactly is included and do the measurements match my engine?

The kit is sold as a complete clutch set engineered for GY6 50cc 4-stroke 139QMB engines so you get both drive and driven assemblies plus the belt in one package. Physical specs are provided so you can verify fitment before installation.

• Clutch assembly: 22 splines inside the drum; spline ID 12 mm.
• Drum dimensions: outer diameter 115 mm, inner diameter 105 mm.
• Variator roller size: 16×13 mm; belt specification: 669x18.1.
• Package content: 1 clutch assembly, 1 variator assembly, 1 669 belt.

What materials and build quality can I expect?

SEHNSUCHT uses durable metal alloys to withstand the heat and friction common to small-displacement CVT systems. The mix of iron and aluminum improves strength where needed while allowing heat dissipation where beneficial, lengthening part life under normal use.

• Clutch/drum constructed in premium iron for wear resistance under centrifugal load.
• Variator components use aluminum where weight and cooling matter for RPM control.
• Rollers and clutch pads sized to OEM-like tolerances for consistent performance.
• Complete kit reduces risk of mismatched parts or premature failure from partial replacements.

Is installation straightforward and what support is available?

Installation follows standard GY6 clutch and variator procedures: disassemble the CVT cover, remove the old drum and variator, and replace with the supplied assemblies and belt. If you encounter fitment or installation questions, SEHNSUCHT provides after-sales support to help troubleshoot issues.

• Plug-and-play replacement for most 139QMB-based 50cc scooters and ATVs.
• Includes clear package contents so you can confirm every part before starting work.
• Technical support available through the seller’s after-sales service policy.

Who is this for: This SEHNSUCHT Fit for Gy6 50cc Clutch Assembly Kit is for owners and mechanics of GY6 50cc 139QMB-engine scooters and ATVs who want a full drivetrain refresh—especially when clutch slipping, worn rollers, or a brittle belt is degrading ride quality. It’s suitable for DIYers with basic mechanical skills and for shops that prefer to replace all CVT wear items in one service visit.