Universal Parts QMB139 50mm Big Bore Cylinder Kit
Universal Parts QMB139 50mm Big Bore Cylinder Kit
$79.49
Out of stock
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Product Details
Description
Universal Parts QMB139 50mm Big Bore Cylinder Kit
Replacement Part Details
Use this part when the original component is worn, damaged, missing, or no longer working correctly. Many scooter parts can look similar but use different sizes, plugs, brackets, thread patterns, or mounting styles, so careful comparison before purchase is recommended.
Compatibility / Fitment
Use the fitment details below to confirm this part matches your scooter before ordering.
- Engine Size: QMB139
- Engine Code: QMB139
- Fitment Notes: Big Bore, Universal Fit
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 QMB139 engine?
A: This SKU is listed as compatible with QMB139 engine-code fitment. Always compare your original part and scooter details before ordering.
Q: Is this for QMB139 scooters?
A: This SKU is listed with QMB139 engine-size fitment. Confirm exact model, year, and part style before ordering.
Additional information
| Weight | 2.2 lbs |
|---|---|
| Dimensions | 6.5 × 5.5 × 4.5 in |
| Condition | New |
|---|
This Universal Parts 50mm Big Bore Cylinder Kit fits 50cc 4-stroke 139QMB engines, upgrading bikes to 81.3cc based on a stock stroke of 41.4mm!
- Includes cylinder, piston, pin, circlips, rings, head gasket and base gasket
- Bore: 50mm
- Overall Height: 70.5mm
- Cylinder Sleeve Outer Diameter: 53mm
139QMB-based 50cc / 80cc engines with the following engine codes:
| 139QMA | 139QMB | 1P39QMB | 1P39QMA-2 |
| YN139QMB | JJ1P39QMB | 139FMA-2 | BD1P39QMB |
| BN139QMB | 147QMD | Other QMA models | Other QMB models |
Don't see your engine listed? If the engine code includes "QM" or "FM", this product is compatible with your vehicle.
NOTE: You may need to modify your engine case to accommodate the larger cylinder.
About Scooterworks: Since our beginning in 1989, Scooterworks has become a major supplier of parts and accessories for vintage and modern scooters. We have everything you need, from wear-and-tear items like tires and oil filters to after-market parts from brands like Malossi, NCY, Prima, YSS, Dr. Pulley, and more.
