Scooter Big Bore Performance Kit, Fits The QMB139/GY6 Based 50cc Four Stroke Chinese Scooter Engines. (Note exhaust brackets may have to be adjusted or moved for long case engine). The item "Scooter Big Bore Kit 100cc 50mm Bore QMB139 Scooter Performance Parts Kit5chrom" is in sale since Thursday, April 30, 2020. This item is in the category "eBay Motors\Parts & Accessories\Scooter Parts\Other Scooter Parts". The seller is "scooter-parts1" and is located in Statesville, North Carolina.This item can be shipped worldwide.