The Honda CRF series is a line of four-stroke motocross, trail, and dual sport motorcycles manufactured and marketed by Honda.
The CRF line was launched in 2000 as a successor to the Honda CR series. The full sized motocross bikes are equipped with liquid-cooled, single cylinder four-stroke engines that are available from 149 cc (9.1 cu in) to 449 cc (27.4 cu in). They now have dual-sport motorcycles. The more trail friendly CRF's have simple air-cooled engines, and are available from 50 cc (3.1 cu in) to 250 cc (15 cu in). The Honda CRF450R was the first in the series, followed by the CRF250R in 2004. Further down the line, the CRF450X and CRF250X bikes emerged, both designed for mostly off-road use. They are considered among the best motocross bikes of their class, and have been a leading seller since their introduction.[1] The CRF450R was CycleWorld's Best Motocrosser for a record eight consecutive years from 2002-2009.[2]