Welcome to the TBoltUSA Tech Database! To visit our store, click here, or use the menus at the top of the page.
Square Bore - An engine with the same bore x stroke , example 54mm x 54mm
Under Square - An engine with smaller bore than stroke , example 52.4mm x 57mm
Over Square - An engine with a larger bore than stroke , example 51mm x 57mm
Deck height - The distance from the top edge of the cylinder to the outer edge of the piston crown at top dead center.
Pin height - The distance from the center of the wrist pin to the upper edge of the piston crown or face.
Our engines use the Honda bolt pattern, and bolt into Z50, XR50, CRF50, CT70, CL70, SL70, XL70, ATC70, TRX70, DAX70, TRX90, Extreme, SDG, Sikk, Pitster Pro, Coolster, Orion, Thumpstar, OGM, Pit Pro, G2Moto, Braaap, Apollo and SSR pit bikes.
Our tech database has info about most common pit bike repairs, upgrades and troubleshooting. If you have a tip, drop us a line!
T Bolt USA, LLC
contact@tboltusa.com
(215) 800-0026
Alt: (704) 826-5887
Our main warehouse, shop & offices are in Pennsylvania, but we often ship from other warehouses around the country.
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