Now, there’s a new version for the 2017 model year and Honda claim that the bike will provide the much desired “...hard-hitting, useable power and a chassis that allows riders of all experience levels to put every drop of that power to good use.”
A word from the man himself
Mr M.Uchiyama, Large Project Leader (LPL) 17YM CRF450R said “This is a full model change for the CRF450R. Nothing has been overlooked, and we have been relentless in our effort to provide customers with a machine that’s ahead of the pack. Our focus has been on producing a machine with exceptional engine performance, outstanding rear wheel traction and a low centre of gravity – to create a 5% improvement in acceleration on the previous model. The phrase underpinning development was ‘Absolute Holeshot’.”
A new engine?
The bike features a new engine, with an 11% increase in peak power matched to an improved chassis. And as MX1-class machines are all about competition, both 16YM and 17YM machines were raced back to back by HRC in a series of start simulations. The power and drive of the new bike saw it gain a significant advantage. 0-10m took 1.53s, 6.4% less time than the outgoing machine.
The new motor produces that much-improved output as a result of straight passageways on the intake side of the motor which reduce air resistance significantly for improved combustion efficiency. On the exhaust side, twin pipes divide close to the engine, facilitating the increase in compression ratio from 12.5 to 13.5, a key element in the greater power output. The cylinder head was also completely redesigned with a Unicam four-valve head, with a finger rocker arm on the inlet valves increasing valve lift by 0.5mm to 10mm (exhaust valve lift is also increased, by 0.85mm to 8.8mm).
Suspension tweaks
A 49mm Showa USD fork – steel sprung and developed from a race-ready factory item supplied to MX race teams in the Japanese championship – replaces the KYB air fork. The aluminium frame’s main spars are now tapered for more front-end stability and traction, and the 17YM CRF450R has completely revised geometry; it’s shorter in wheelbase, with a more compact swingarm and adjusted rake and trail. It also has a lower centre of gravity thanks to details like a lightweight titanium fuel tank and lower upper shock mount. There are also Dunlop’s MX3SF and MX3S soft terrain tyres fitted to the new machines.
A new look
The bike also features new plastics which create improved aerodynamic performance, and a smooth, ‘organic’ shape to give the rider ultimate freedom to move. They also feature film insert graphics for an improved look. The bike is also available with electric start as an option, for the first time.
Switchable engine modes
Honda’s EMSB (Engine Mode Select Button) also features on the 2017 model. It allows for riders to adjust the bikes engine characteristics. With the machine stopped, and engine at idle, a simple press and hold of the button for just under a second selects the next map in sequence. The LED built into the button signals the map in use with a quick press and number of subsequent flashes (1 flash for Mode 1, etc). If a new map is selected the choice is also confirmed to the rider.
Mode 1 uses the standard combination of ignition and fuelling maps to present a balanced power and torque delivery. Mode 2 is more mellow in nature, giving easy-to-manage throttle feel. Mode 3 hits sharply, with aggressive and responsive power. Mode 2 and 3 can be further tailored via the existing HRC setting tool for mapping hardware and software.
Give us some figures
The new model features a 6.3 litre fuel tank, has a kerb weight of 110.6kg, a 260mm wave-pattern front brake disc with a matching 240mm wave-pattern disc at the rear while the bikes centre of gravity is 2.7mm lower and its wheelbase some 11mm shorter. These tweaks should make the CRF450 as competitive as ever.
