Honda's 2011 model CRF450R has limited refinements for the new year.

Honda has released information on its 2011 model motocross bikes, the CRF450R and CRF250R four-strokes receiving limited refinements for the new year.

Long regarded as the bike of choice in the big-bore motocross division, the 2011 CRF450R incorporates improvements that will help this bike retain its premier standing.

The prodigious powerband is now even stronger thanks to more low-end pull and midrange grunt along with enhanced throttle response via a new 46mm throttle body.

Its front fork features a lighter cartridge cylinder and all-new valving for improved control and increased ride plushness. Revised suspension linkage and settings yield improved control, increased ride plushness and enhanced rear-wheel traction.

A new 24mm (up from 20mm) Honda Progressive Steering Damper (HPSD) produces even better tracking traits than before, and a new muffler meets the 94-decibel sound level required by some racing organizations in 2011.

All this and more make the 2011 CRF450R a favourite to maintain its dominant role among open-class motocross bikes.

Despite winning numerous comparison tests and awards in 2010, the CRF250R enters the new season sporting a number of improvements that will help it continue its winning ways.

A new Honda Progressive Steering Damper (HPSD) with a larger, 24mm damper piston aids tracking precision, and new suspension settings front and rear help give this stellar-handling machine even better chassis balance for 2011.

Revised fork valving offers improved balance and bottoming resistance, while a new shock valving helps deliver optimum chassis balance and improved suspension action.

Changes to engine tuning now give the CRF250R a stronger bottom-end and mid-range hit, and this model also features a new muffler that meets the 94-decibel sound level required by some racing organisations in 2011.

LIke its big brother, the 2011 model CRF250R has also received just minor changes.