Prima Roller Weight Tuning Kit (15×12)
Prima Roller Weight Tuning Kit (15×12)
$47.06
10 in stock
*Note: Free shipping to U.S. mainland (excludes AK, HI, and territories)
Orders placed by 1pm EST on weekdays ship the same day.
Product Details
DESCRIPTION: The Prima Roller Weight Tuning Kit (15×12, 2g-13g) is the best way to tune the CVT transmission in a Yamaha Jog or Zuma 50cc engine, as well as many Minarelli clone motors noted below.Specifications:Includes 3 of each roller in sizes ranging from 2g to 13g, for a total of 36 weights.Combining 2 sets of rollers allows you to tune your engine with a large variance in weight. For example, using the set of 10-gram rollers and the set of 12-gram rollers, alternating weights in variator results in an 11-gram roller set. Using the set of 10-gram rollers and the set of 11-gram rollers, alternating weights in variator, results in a 10.5-gram roller set.Lighter weights increase RPMs for a given road speed, while heavier weights lower RPMs for a given road speed.Tailor your tuning to match your engine setup and personal driving style.Compatibility:Yamaha Zuma 50 2-StrokeYamaha Jog 50Yamaha Vino 50Yamaha C3Minarelli Clone engines1E40EQMB Engines1E41QMB Engines1PE40QMB Engines*DANGER: Weights must be installed in a 120-degree pattern! If not, SEVERE ENGINE DAMAGE WILL RESULT!!!Please refer to our handychartfor more info on roller weights. Visit ourblogfor additional tips and news.About Prima:Prima is the industry leader in premium scooter accessories, service parts and scooterist protective apparel. Prima brand products are designed direct-fit for all popular scooter brands including Honda, Yamaha, Genuine, Vespa, SYM, Lance, KYMCO, Royal Alloy and GY6 / QMB powered scooters.Made in Taiwan.WARNING: Californiaâ„¢s Proposition 65
SPECIFICATIONS: Includes 3 of each roller in sizes ranging from 2g to 13g, for a total of 36 weights.Combining 2 sets of rollers allows you to tune your engine with a large variance in weight. For example, using the set of 10-gram rollers and the set of 12-gram rollers, alternating weights in variator results in an 11-gram roller set. Using the set of 10-gram rollers and the set of 11-gram rollers, alternating weights in variator, results in a 10.5-gram roller set.Lighter weights increase RPMs for a given road speed, while heavier weights lower RPMs for a given road speed.Tailor your tuning to match your engine setup and personal driving style.
COMPATIBILITY: Yamaha Zuma 50 2-StrokeYamaha Jog 50Yamaha Vino 50Yamaha C3Minarelli Clone engines1E40EQMB Engines1E41QMB Engines1PE40QMB Engines*DANGER: Weights must be installed in a 120-degree pattern! If not, SEVERE ENGINE DAMAGE WILL RESULT!!!Please refer to our handychartfor more info on roller weights. Visit ourblogfor additional tips and news.About Prima:Prima is the industry leader in premium scooter accessories, service parts and scooterist protective apparel. Prima brand products are designed direct-fit for all popular scooter brands including Honda, Yamaha, Genuine, Vespa, SYM, Lance, KYMCO, Royal Alloy and GY6 / QMB powered scooters.Made in Taiwan.
NOTE: d below.
Compatibility / Fitment
Use the fitment details below to confirm this part matches your scooter before ordering.
- Engine Size: 50cc, GY6, Minarelli
- Fits Models / Common Applications: Yamaha Zuma and other compatible models may apply.
- Fitment Notes: CVT, Clone / Chinese, Auto Transmission
Fitment Guide: This compatibility information is based on manufacturer and supplier data. Listed models are common known applications and may not include every compatible scooter. If your scooter has multiple versions or production changes, confirm the correct match before ordering. Check photos, measurements, original part numbers, engine code, model, and related fitment information whenever possible.
Common Fitment Questions
Q: Will this fit a Yamaha?
A: This SKU is listed with Yamaha model fitment where the scooter also matches the listed engine or fitment notes.
Q: Is this for 50cc scooters?
A: This SKU is listed with 50cc engine-size fitment. Confirm exact model, year, and part style before ordering.
Additional information
| Weight | 1 lbs |
|---|---|
| Dimensions | 10 × 7 × 1 in |
| Size | 15×12 |
| Condition | New |
|---|
The Prima 15x12mm roller weight tuning kit gives you 36 color-coded rollers — 3 of each weight from 2g to 13g — to dial in your CVT transmission for your riding style, engine build, and rider weight. Designed for Yamaha Jog/Zuma/Vino/C3 50cc 2-stroke engines and Minarelli clone motors (QMB139 horizontal). Made in Taiwan. SKU: 1400-1083.
- 36 rollers total — 3 of each weight from 2g to 13g in 1g increments
- Color-coded by weight for easy identification
- Mix and alternate weights to achieve half-gram increments (e.g., alternating 10g and 11g = effective 10.5g)
- Lighter weights: higher RPM for a given speed — better acceleration
- Heavier weights: lower RPM for a given speed — higher top speed
- Fits 15x12mm variator roller pockets
- Made in Taiwan by Prima | SKU: 1400-1083
Tuning Guide
- Lighter (2g–6g): higher RPM, stronger acceleration — best for heavier riders, stock motors, or hill climbing
- Heavier (7g–13g): lower RPM, higher top speed — best for lighter riders or big-bore builds
- Mixing weights: alternate two adjacent weights in the variator to achieve half-gram increments
- Always install rollers in a 120-degree pattern (every other pocket) — uneven installation will cause vibration and variator damage
- Roller Dimensions: 15mm diameter x 12mm width
- Weights Included: 2g, 3g, 4g, 5g, 6g, 7g, 8g, 9g, 10g, 11g, 12g, 13g (3 of each)
- Total Quantity: 36 rollers
- SKU: 1400-1083
- Origin: Taiwan
| Make | Model / Engine |
|---|---|
| Yamaha | Jog 50 (2T) |
| Yamaha | Zuma 50 (2T) |
| Yamaha | Vino 50 (2T) |
| Yamaha | C3 50 |
| Various | Minarelli clone engines (horizontal) |
| Various | 1E40EQMB, 1E41QMB, 1PE40QMB engine codes |
For stock roller weight reference, see our roller weight chart. Additional tuning tips on the Scooterworks blog.
