MXA NEW PRODUCT:
MILLENNIUM TECHNOLOGIES/CP PISTON HONDA CRF264 BIG BORE KIT: HOW TO GET MORE JUICE FROM YOUR 2010 HONDA CRF250
With earlier model Honda CRF250’s (2004-2009), it was difficult to big-bore the engine much past 256cc without endangering the cylinder liner’s structural integrity (or resorting stroking the crank). No more! Thanks to a cooperative effort between Millennium Technologies (www.mt-llc.com) and CP Piston (www.cppistons.com) it is now possible to build (at a reasonable price) a 264cc Honda CRF250. The catch? You can only do it on the 2010 model.
The thicker stock liner of the 2010 CRF250 allows the CRF250 cylinder to be bored and replated to 79mm (stock bore size in 76.8mm). This is a simple remove from your bike and ship to Millennium Technologies job. The retail cost for the cylinder work is $234.95.
Then, when you get the cylinder back from Millennium Technologies, you slip in a 13.5:1, 79mm, Forged CP piston ($278.00).
The only other parts you need is a Cometic gasket kit set ($47.67) from www.cometic.com.
The big-bore engine runs the stock cam and stock ignition mapping. For more information about how this kit runs, you can see a full test on page 112 of the March 2010 issue of MXA.
For more information visit their websites or call Millennium Technologies at (920) 893-5595 or CP Piston at (949) 567-9000.