Big Bore Cylinder set for 50cc 2-stroke Minarelli JOG Yamaha engines found on many popular 2-stroke full size scooters and ATVs such as Malaguti, Yamati, United Motors X-Speed, Aprilla, CPI, Benelli, Vento, Eton, Adly and many more. Italian made units tend to use 10mm pins (Chinese JOG 2T clones tend to use 12mm) please measure and check before ordering. Certain brands such as CPI / United Motors / Muz older models used 10mm newer post 2004 use 12mm. All Italian made models use the 10mm such as Aprilia / Malaguti / Italjet that are Yamaha Minarelli based Specifications * Wrist Pin Diameter: 10mm * Wrist Pin Length: 36.8mm *Displacement: 70cc *Fits 1PE40QMB Minarelli based engines with 10mm wrist pin * Piston Diameter: 47mm * Please see below for measurements * The MRP Cast Iron Cylinder increases you displacement, giving you more power. MOre power converts to faster acceleration and higher top end. * Cast-iron cylinder kits are the best balance between component performance and component life * Check model before ordering to see if it's JOG based and 10mm Geely Model 18, TGB Several Models, Vento Zip R3i, Various unlisted makes/models, Diamo, Yamaha, Eton, 40QMB 50cc 2-stroke