KX139 Big Bore

Motorcycle Kawasaki KX 139

Please call to order 608-842-0680

Special Price: $549


Quick Overview

Kawasaki KX139 Fits the 1999-Current KX125


Product Description

Actual Displacement = 139.07cc

Engine Modifications Required:

Cylinder: Bore, Port and Plate.

Power Valves: Precision machined to match big bore cylinder.

Head: Re-chamber to work with the Big Bore piston. 100 octane suggested for most conditions.

Crankshaft: No crank mods required.

Crankcase: No crankcase mods required.

Notes: This kit requires you to send us your cylinder, head, and power valves for modification.

The Max Power KX139 is the best bore-only kit we offer for the Kawasaki KX125.  Max Power’s 57 mm 2-ring Custom Wiseco piston we use is lighter than the stock KX125 piston and since it has 2 rings it seals compression better and longer.

This is also the largest bore-only kit we offer for the 2003-2007 KX125 because if you go larger on those without welding the top up you will have trouble with blowing out the o-ring grooves.

The over-rev on the Max Power KX139 is substantially better than the KX144 and the bottom and mid are very comparable.



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