YZF / WR 300cc Yamaha Big Bore / Long Rod Stroker YZ250F WR250F

Motorcycles Yamaha YZF WR 300cc

Please call to order 608-842-0680

Availability: Built to order

Regular Price: $2,495

Special Price: $1,950


Product Description

For: 2001-2013 YZ / WR 250F


Cylinder: Install longer forged Aluminum sleeve, and plate with Ceramic Nickel Bore coating.  Copper fire ring installed around combustion chamber.

Crankshaft: Stroked and balanced with long rod, new pin, and lower bearing installed.

Wiseco or CP Piston kit

Necessary Gaskets

Base Spacer Plate

Longer Cam Chain

Longer Chain Guides

Longer head bolts

Oil line, coolant spacers, dowel extenders.

No Case Mods Required


This price is to modify your cylinder and crankshaft.  Call us if you need a cylinder and crankshaft.

Upper head mounts must be modified to clear taller cylinder, we do not provide instructions to do this.

This kit uses a huge stroke and slightly bigger bore. The torque gains are massive but the engine still revs quickly and pulls out on top like a smaller 250F. Durability is very, very good. It is a great choice for hybrid youth ATV’s and vets that like a small 250f but hate getting yarded by 450’s on the hole shot.


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