TB Parts 88cc Big Bore Kit for Honda Z50/XR70/CRF70/CT70 - See Years Below! Add some performance to your pit bike! High quality parts that you have come to expect from TB Parts. This is a bolt on kit with no case boring required. Comes with everything you need to install as shown. This is a 52mm bore - we also carry replacement pistons, rings, and gaskets for these kits. Bolt on some power and make your 50 or 70 way more fun to ride. Race camshaft for stock head included in this listing. Add even more power to your bike! We also recommend installing the TBW0226 high volume oil pump when installing this kit. We have them listed separately or also included with one of our big bore kits. It saves a ton of time installing the oil pump at the same time since removing the cylinder is required to install the oil pump. 

Some key features of this kit:

• Lightweight aluminum cylinder with steel sleeve
• Cast in mounts on cylinder for aftermarket skid plates
• Oversized cooling fins on cylinder for efficient heat dissipation
• High compression 52mm piston with rings, pin, & clips
• Head/Base gasket kit, With exhaust gasket.
• Race camshaft to increase power! TBW0189
  

Fits:

• Honda Z50 1982-1987
• Honda XR70 All Years
• Honda CRF70 All Years
• Honda CT70 1991-1994
  

There are no installation instructions, but if you can replace your piston, you can install this kit as the parts are installed in the same manner as the OEM parts. However, its highly recommended that a professional install this kit and make sure its tuned and jetted properly.