Here is the big bore engine top proposed by ATHENA to increase the displacement of your motocross / enduro YAMAHA WR in 250cc 4 stroke from 2008 to 2017. This kit in Ø83mm against Ø77mm of origin thus makes it possible to pass your motor bike of 250cc has 290cc real! A gain of torque and performance will be immediately felt. It allows a gain of 8 HP and 5 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 WR 250 R 250cc 2008

YAMAHA WR 250 R 250cc 2009

YAMAHA WR 250 R 250cc 2010

YAMAHA WR 250 R 250cc 2011

YAMAHA WR 250 R 250cc 2012

YAMAHA WR 250 R 250cc 2013

YAMAHA WR 250 R 250cc 2014

YAMAHA WR 250 R 250cc 2015

YAMAHA WR 250 R 250cc 2016

YAMAHA WR 250 R 250cc 2017

YAMAHA WR 250 X 250cc 2008

YAMAHA WR 250 X 250cc 2009

YAMAHA WR 250 X 250cc 2010

YAMAHA WR 250 X 250cc 2011

YAMAHA WR 250 X 250cc 2012

YAMAHA WR 250 X 250cc 2013

YAMAHA WR 250 X 250cc 2014

YAMAHA WR 250 X 250cc 2015

YAMAHA WR 250 X 250cc 2016

YAMAHA WR 250 X 250cc 2017