{"product_id":"50cc-139qmb-scooter-go-kart-engine-crankcase-cover","title":"50cc 139QMB Scooter \u0026 Go-Kart Engine Crankcase Cover","description":"Here is a 50cc 139QMB scooter \u0026amp; go-kart engine crankcase cover for those popular 4-stroke 139QMB engines that put the power to so many of today's 49\/50cc motor scooters. These are probably the most common scooter and go-kart engines, and many millions have been made over the years.\nTwo styles are available, the long case and the short case versions. Both sport a nice black finish.\u003cbr\u003e\u003cbr\u003e\nThe \u003cb\u003eshort case\u003c\/b\u003e engine is designed for use with 10\" diameter rear rims. This would correspond to a tire size of 2.75-10 through 3.50-10. A short case engine will not accommodate rear tires that are larger than 3.50-10.\u003cbr\u003e\u003cbr\u003e\nThe \u003cb\u003elong case\u003c\/b\u003e engine is designed to allow the use of 12\" rear rims. This would correspond to a tire size of 110\/70-12 through 140\/70-12. Please use your rear tire size to determine which crankcase cover is right for your go-kart or street-legal motor scooter.","brand":"Monster Scooter Parts","offers":[{"title":"Long Case","offer_id":44393189245090,"sku":"X98-6746-001","price":18.99,"currency_code":"USD","in_stock":false},{"title":"Short Case","offer_id":44393189277858,"sku":"X98-6746-002","price":18.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0627\/6943\/0690\/files\/x98-6746_1.jpg?v=1774839896","url":"https:\/\/monstorscooterparts.shop\/products\/50cc-139qmb-scooter-go-kart-engine-crankcase-cover","provider":"Monster Scooter Parts","version":"1.0","type":"link"}