RCB E2 SERIES BRAKING SYSTEM
RCB S1 SERIES BRAKING SYSTEM
UMA Racing CVT Pulley Kit Drive Face V3 is an ultra-high-performance transmission upgrade engineered specifically for Yamaha 155cc VVA scooter engines (NMAX, NVX, Aerox). Re-engineered with a 13.8° pulley surface angle and ultra-smooth roller tracks, the V3 edition delivers explosive low-to-mid range acceleration, improved throttle responsiveness, and higher top-speed capabilities by maximizing belt travel across the drive faces.
Key Features
13.8° Race-Calibrated Pulley Angle: Re-angled drive face profile (compared to stock 14°) allows the V-belt to ride lower for a punchier initial launch, while enabling higher belt travel at peak RPM for elevated top speed.
CNC Precision-Machined Billet Alloy: Cut from high-density aluminum alloy to reduce rotational weight, lowering engine inertia for instant throttle response and faster engine spin-up.
Ultra-Smooth Low-Friction Roller Tracks: Re-engineered ramp channels ensure smooth, binding-free roller travel, preventing roller flat-spotting and guaranteeing consistent shifting across the powerband.
High-Velocity Airflow Cooling Fins: Integrated fan blade profiles on the fixed drive face generate intense internal airflow throughout the CVT casing to rapidly lower operating temperatures and prevent belt fade.
Hard-Anodized Surface Protection: Chemically hardened face treatment resists belt wear, slippage, and scoring under heavy thermal and torque loads.
Exact Vehicle Compatibility
This UMA Racing V3 CVT Pulley Kit is designed for direct plug-and-play installation on the primary drive shaft of the following models:
Yamaha NMAX Series:
Yamaha NMAX 155 V1 (2015–2019)
Yamaha NMAX 155 V2 / Connected (2020+)
Yamaha Aerox / NVX Series:
Yamaha Aerox 155 / NVX 155 V1 (2016–2020)
Yamaha Aerox 155 / NVX 155 V2 Connected (2021+)
Engine Engine Platform: Fits all Yamaha 155cc VVA Liquid-Cooled 4-Stroke Blue Core engines.
Technical Specifications
| Feature | UMA Racing CVT Pulley Kit V3 Details |
| Brand Origin | UMA Racing |
| Product Series | CVT Pulley Kit Drive Face V3 |
| Primary Material | CNC-Machined Billet Aluminum Alloy |
| Drive Face Surface Angle | 13.8° Re-engineered Performance Profile |
| Target Engine | Yamaha 155cc VVA Blue Core Platform |
| Included Components | Movable Drive Face, Fixed Drive Face (Fan Plate), Ramp Plate, Slider Bushings |
| Performance Objective | Eliminates acceleration dead spots, improves belt climb, elevates top speed |
Product Structural Form & Mechanical Dynamics
The V3 pulley kit comprises two matched primary drive sheaves: the movable drive face featuring extended roller weight channels and the fixed fan drive face with high-efficiency cooling fins. The kit includes an alloy ramp plate fitted with low-friction slider bushings to maintain perfect sliding alignment along the drive collar. The 13.8° face geometry widens the effective gear ratio range of your scooter’s automatic CVT without overloading the engine crank.
CVT Tuning Safety Notice: Always ensure the V-belt has adequate slack when torquing down the primary crankshaft nut. Clamping the drive face onto a pinched belt instead of flush against the center collar boss will cause the crankshaft nut to loosen during operation, resulting in stripped crankshaft splines and expensive crankcase repairs.
