What engine family is the 400 EXC from?
What engine family is the 400 EXC from? I’m asking if I can take the crank and/or cylinder and head from a different bike and make it bigger.
All RFS motors have the same cases. From 250 up to 570. The differences are in the crank and bore sizes. By mixing and matching you can build all different kinds of configurations. The 400 has a short stroke crank. For instance, you can build a short stroke 450 or a long stroke 450 by using different cranks and piston diameters. Or use the stroker crank and a 540 kit to build the 570 monster! I own a 400 exc and it is an absolute sweetheart of a bike. I love the way it buzzes down the trail. I actually own a 400, a 450 and a 525 all RFS’s, all awesome.