Here is the big bore kit proposed by ATHENA to increase the displacement of your motocross / enduro YAMAHA YZF and WRF in 250cc 4 stroke from 2014 to 2017. This kit in Ø81mm against Ø77mm of origin thus makes it possible to pass your motor bike of 250cc has 276cc real! A gain of torque and performance will be immediately felt. It allows a gain of 3 HP and 2 NM on average which is huge on this vehicle. Enough to have fun on the tracks or in the forest. ATHENA has also planned things well because this top engine is sold complete. It includes the cylinder, piston, ring as well as all the gaskets you need for a quality and tight reassembly. The advantage of taking this engine is that it is designed to be mounted on the original connecting rod with the original cylinder head and camshaft. So you have no modification to do or adjustment! Here attached the power curve so you can see by yourself the difference between the original and the big bore. You will also find a detailed list of vehicles on which this cylinder can be mounted.

Fits on:

YAMAHA YZF 2014

YAMAHA YZF 2015

YAMAHA YZF 2016

YAMAHA YZF 2017

YAMAHA WRF 2015

YAMAHA WRF 2016

YAMAHA WRF 2017