TB parts 170cc big bore kit. This will make your KLX140 a lot more fun to ride by adding some much needed power! Includes a brand new lightweight 63mm Piston kit with rings, pin, and pin clips. Matching 63mm aluminum cylinder with HD cast in steel sleeve. Plus our high quality top end gasket kit with new dowel pins for an easy install! Combine that with our performance cam to really wake that KLX140 up! Our cam opens the valves up faster and provides more lift to let even more air and fuel in for even more power! Great for playbike racing and idles low enough to use on the trails too!

Key Features:

• Lightweight piston Kit w/ Wrist Pin, Ring Set, Cir-clips
• Safe with 91+ octane Pump Fuel
• TB parts 63mm aluminum cylinder with HD cast in steel sleeve
• 63mm Top End gasket kit w/NEW dowel pins
• Performance high lift cam, complete with new bearings

Note: 2025+ KLX140s – require case boring to fit. Our cylinder skirt is 65.95mm 2025+ cases are only 65.4mm wide.

There are no installation instructions, but if you can replace your piston, you can install this kit. If you don’t have any experience working on your engine, we highly recommend having a professional technician install this kit or, at a minimum, purchasing the shop manual for your bike available from your local Kawasaki dealer. The parts are installed in the same manner as the OEM parts.

Note – A good jetting base for the factory carburetor is +1 size Pilot jet and +1 or 2 sizes up on the main jet.

Installation note – KLX140 camshaft bolts are reverse threaded, turn them right/clockwise to loosen/remove. Torque to 87 INCH-LBS & Use red thread lock