NCY Cylinder Kit 4T (81cc, Iron, 50mm); 139QMB
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NCY GY6 50/139QMB 50mm bore Cast Iron Cylinder Kit w/o head. The perfect upgrade for most 4T 139QMB/GY6 50 scooters, this bolt-on 81cc kit will really give your scooter some go. It is recommended to get part number 1100-1239, 50mm big valve head as well, as most stock heads will not fit.
In addition, we really recommend 1100-1250, NCY Performance Camshaft as an amazing complimentary item to this kit. It will allow the kit to perform to its maximum potential and go 50-55 MPH!
Have a look at our Decompression Tube Assembly (1100-1282) which replaces your dipstick and allows excess crankcase pressure to be released. Good idea to install one of these alongside any cylinder kit upgrade.
Not legal for use in California on pollution controlled vehicles. Check local laws before installing.
This product is not intended for use on public roads or land.
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Returns & warranty
Please verify fitment and part number before ordering. Contact Thrifty Scooters promptly if an item arrives damaged or incorrect.