Will electric dirt bikes take over motocross? Only time will tell, but the XE4 -- a converted Yamaha YZ250F -- could be a step in that direction, once the bugs are worked out.

CFMoto revealed the 1,000cc V4 engine it plans to put on its Master of Speed superbike concept, but hidden behind all that glitz and glamor was the CF-X, an electric motocross bike that is built ...