50cc QMB139 4-stroke 51mm Racing Big Bore Cylinder set QMB139 moped/scooter performance parts SUNL 50cc performance parts Roketa 50cc performance parts Strada Tank Big chief

"I have owned 5 different scooters over the years. 250cc CFMOTO, Roketa 150cc 4-stroke GY6, United Motors 50cc 2-stroke and a SunL 50cc 4-stroke QMB139. I can rest assured that no matter what make or model I have, Partsforscooters.com will always have the parts I need. I was impressed by your sales staff's knowledge of both stock and performance after-market parts. Shoot...I have a new performance muffler (169-3) for my Roketa 150cc that turned it from BLAH to YAH! Street Scooters, ATVs, Dirt Bikes, you name it and these guys have the parts. Keep rockin and rollin with your excellent service. You have a customer for life!"
Mike R.-California

"I am not a rich man, but I wanted my family to enjoy ATV riding. I bought three different Chinese made ATVs; a 250cc for me, 110cc for my wife and a 110cc for my son. Lots of people said beware, because you can't get parts for them. But, I found you guys online and all 3 of my orders shipped quickly. Beware of nothing, because Partsforscooters.com makes it easy and obtainable on my budget." Jeff A.


	50cc QMB139, Performance Cylinder Kit

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50cc QMB139 4-stroke 50mm, Racing Big Bore Cylinder Set. Kit includes cylinder, piston, rings, piston pin, cir clips, head gasket, and base gasket. **Note: This is a non-returnable item. Please confirm this is the correct item prior to purchasing. Please see our Warranty & Returns for further detail.

Specifications

We recommend that you use our part #169-70 cylinder head with this set as some stock cylinder heads will not fit.

Upgrades to 80cc

Cylinder Bore: 50mm

Wrist Pin Diameter: 13mm

Total Piston Height: 34.8mm

Compression Height (from center of wrist pin hole to top edge of piston): 18.3mm

Please see below for measurements

Supported Models

Jalon X8 Retro 50cc, Panterra Fusion 50cc, Lifan, Qingqi QM50QT-6V, SUNL, Various unlisted makes/models, Strada, Qingqi QM50QT-4G, Baja SC50-P, Schwinn

Part Number: 169-54

Old Part Number: