TB V2 Big Valve Cylinder Head & 138cc Big Bore Kit – 125cc 54x54mm 14mm pin Chinese engines

TB V2 Big Valve Cylinder Head & 138cc Big Bore Kit – 125cc 54x54mm 14mm pin Chinese engines

TBparts V2 Big Valve Cylinder head & 138cc (57mm) Bore Kit for Chinese 125cc Engines 

Want to turn your slow Chinese Lifan 125cc engine into a race ready Rocketship? This kit takes these engines from mild straight to wild! The combination of the +3mm high compression piston and roller rocker big valve head will double the power of the engine with right carb and exhaust. We found the right level of compression for increased performance while also keeping reliability in mind. These will run safe on 91+ octane fuel at approximately 11.5:1 compression. Additionally, it is a very quick and easy upgrade as it does not require case boring. This kit includes everything pictured, our V2 head kit, a 57mm bore cylinder, light weight high revving piston, and a head gasket kit. Bolt on Big power with TBparts!

Key Features:

•  57x69mm cylinder with steel liner
•  High compression large dome 57mm piston with rings, 14mm pin, & clips
•  Head gasket kit
• Complete V2 cylinder head, cam, valves, aluminum roller rockers, cam and tappet covers

Important Note: This kit will only work on Chinese/Lifan style 125cc engines with a 69mm cylinder (base to deck), 54mm stroke, 14mm piston wrist pin, and clutch basket is on the crankshaft. Additionally we have this PDF in our tech section – TBW1608 Bolt Pattern. There are so many Chinese brands/models that you absolutely need to know your stroke and piston wrist pin size. Unfortunately, we are unable to tell you what you have based on a brand name as there are so many unknown Chinese brands.  This kit is also recommended for use only with big valve heads such as the common Lifan head with 27/23mm valves or our V2 Race Head for Chinese engines.

Installation Notes: Do not use the original o-rings between the head and cylinder (not needed) but do use the large o-ring at the bottom of the cylinder between the cylinder and the engine case at the oil return. Our head gasket had build in RTV gasket to seal the oil.