2021 Honda CRF450R fully detailed
Honda has unveiled the latest version of their MX weapon – and it’s razor-sharp.
Depending on where you look in the current environment under COVID-19, motorcycling is either in a bleak state or going well. Road bike sales are down and national racing categories have been unable to complete their seasons – or even start them in some cases.
But look elsewhere and there is some light in the darkness. Dirt bike sales increased a whopping 42.4 per cent in the first half of 2020, and sure, most of the increases were in kids bikes (most likely bought by parents to keep their offspring from going bonkers under lockdown!), but full-sized dirt bikes didn’t miss out, with all the 450-class MXers recording sales gains for the Jan-Jun 2020 period – a good sign for that segment of the industry.
Other positives include a raft of new models that have either arrived or are due to reach our shores soon. For the motocross fraternity, the most eagerly awaited new bike for 2021 would have to be Honda’s radically overhauled CRF450R.
New for ‘21
The 2021 CRF450R is the sixth generation version of a model that brought Honda into the four-stroke motocross age in 2002 and follows the last major overhaul from 2017.
It’s not unfair to say the CRF450R is all-new for 2021, as major changes have been made to the frame, subframe, swingarm, exhaust, clutch, engine internals, switchgear and plastics, just to name a few.
On paper, the changes look impressive, and will no doubt see the new model sought after by Honda riders Australia-wide when it starts arriving here in October. It’s a model that will hopefully deliver Honda some long-awaited championships in national-level MX competition, too.
While Honda has enjoyed supercross success here in recent years and secured the Pro Lites/MX2 championship in 2012, they haven’t won an MX Nationals Pro Open/MX1 title since 2006. That’s a long time between drinks.
Honda says the development theme for the 2021 CRF450R was “razor sharp cornering” and to achieve that goal, improvements have come in power, handling and consistency over the course of a moto.
To achieve the first goal of improved power, four major engine changes have been made.
Firstly, the air filter capacity – on the ‘clean’ side of the filter – has been increased from 1.8 litres to 4.1 litres to improve torque at low rpm. In harmony with this, the injector angle has been opened out from 30 degrees to 60 degrees to improve intake airflow, specifically on the upstream path, which results in better torque feel.
Secondly, the exhaust port has been relocated, has a straighter path and now features a centralised oval-shaped opening to improve exhaust efficiency and enhance mid-range engine performance.
Thirdly, the layout of the decompression system in the Unicam engine’s cylinder head has seen the counterweight moved from the right side to the left, which is claimed to improve combustion stability at low rpm and resist stalling. The head itself now uses a thinner casting to reduce weight, with the throttle body and fuel pump now lighter, too.
Finally, the most obvious departure from this year’s CRF45R for 2021 is the switch to a single muffler exhaust system.
The twin-muffler exhaust was introduced with the fourth-generation CRF450R in 2013 (supposedly in an effort to improve mass centralization) and remained a Honda oddity – none of their rivals in the 450 MX class went down the same path. Now, it seems, Honda has found alternative ways to improve mass centralization, or perhaps it’s more accurate to say other componentry has been lightened to the point where such measures are no longer necessary. Either way, going from two pipes to one (on the offside) has chopped a significant 1.2kg from the exhaust system’s weight.
The other benefits of the new exhaust system include a more direct path for spent gases and slimmer overall width both front and rear. The centralized exhaust port allows the header pipe to be routed 74mm closer to the engine, while removing the second muffler has allowed the 2021 CRF450R’s back end to be 70mm narrower than the current model.
While the engine’s bottom end is unchanged, the changes made everywhere else on the 450cc single add up to around 0.6kW more power over 5000rpm. Not a huge gain, but the more significant result is increased torque at low- and mid-rpm, which Honda say makes for more manageable power control over the course of a moto, especially when cornering.
While there are some obvious visual cues defining the 2021 CRF450R against the 2020 model, less apparent are changes to the frame, subframe and swingarm, all of which have gone on a diet for 2021.
Starting with the frame, the main spars are narrower, with changes also made to the reinforcement ribbing on the back of the pivot plates. Narrowing the spars has shaved just under 700gm off the frame weight, with lateral rigidity reduced by 20 per cent, but no change in vertical rigidity. This, Honda says, improves cornering performance by providing a degree of chassis flex without compromising stability.
The subframe has been redesigned so it no longer needs a support structure, saving a further 300gm for a new weight of 900gm.
Finally, the swingarm is narrower, for improved clearance when negotiating ruts, and stiffer to improve traction on corner exit.
To make best use of these changes – and achieve that razor-sharp cornering goal – the new CRF450R’s geometry has been changed in almost every measure. Compared to the 2020 CRF450R, wheelbase on the 2021 model is 1mm shorter at 1481mm and a steeper 27.7-degree rake cuts the trail to 114mm (2mm shorter). The swingarm angle is 0.9 degrees steeper at 14.5 degrees, which contributes to an 8mm increase in ground clearance – now at 336mm. Upping the ground clearance has increased seat height, too, from 960mm to 965mm.
Total weight has been reduced by 1.43kg to 110.6kg (wet), which is significant in MX terms and will certainly be felt over the course of a moto.
Working with the frame and geometry modifications, the suspension has been tweaked, too. There’s a 5mm increase in stroke from the 49mm USD Showa coil-spring fork, with a new axle holder design introduced. The upper and lower triple clamps have also been redesigned, aimed at improving feel on corner entry and co-ordinating with the rake/trail changes.
Settings on the Showa rear suspension have been revised, with the shock unit mildly modified to suit the frame changes (adjusters are now on the left side) and a new, ultra-lightweight spring added. Pro-link ratios have been altered in an effort to reduce back-end ‘packing’ under acceleration.
2021 Honda CRF450R – key changes
• Modified frame, subframe and swingarm
• Revised air filter system
• Single-sided exhaust and muffler
• Hydraulic clutch
• Revised triple clamp design
• Revised front and rear suspension
• Integrated left-hand switch block
• Redesigned radiator shrouds and bodywork
• Reduced weight
• Increased power
Most of the aforementioned changes contribute to more consistent performance over the course of a moto, particularly the reduced weight and improved low-end torque, but another key change on the 2021 CRF450R not already mentioned is the adoption of an improved clutch for the five-speed gearbox.
Clutch capacity has been increased by a significant 27 per cent, with an eighth clutch plate added, as well as a new friction spring. But the more significant change is the adoption of hydraulic clutch operation that was previously limited to the HRC works bikes. The result is lighter, easier lever pull and less clutch slip over the course of a moto.
A big part of riding consistency is rider comfort and ease of use. Some of the changes made in this area include the seat, which looks familiar on the outside, but is now mounted with the tongue at the rear and fasteners at the front, so if it comes loose during a moto, momentum and rider position is more likely to keep it in place. The slimmer cross section allows easier fore and aft rider movement, too.
The switchgear has been simplified to two elements, with the left-side switchblock now incorporating the Honda Selectable Torque Control (HSTC, aka traction control, that was introduced for 2020) with the engine mapping selector and killswitch in one unit for a saving of 98gm. HRC Launch Control and the electric starter are on the right-side switchblock. A choice of three engine map settings remains (Standard, Smooth and Aggressive), as do three levels of HSTC intervention and three-level Launch Control.
The slimmer cross section and reconfigured exhaust set-up has allowed the CRF450R’s radiator shrouds and side plates to be redesigned for 2021, with the shrouds now in a one-piece design that offers better airflow, while the side plates have been reshaped. A total of eight bolts are needed to fasten the plastics on both sides (down from 12), and that reconfigured exhaust layout has removed the need for a heatshield.
Rerouting the control cables to behind the four-position adjustable Renthal handlebar, rather than in front, seems insignificant but Honda says it reduces weight at the top of the bike. It’s small changes like this that all contribute to the aforementioned total weight reduction.
Black DiD rims carry over unchanged and braking is unchanged, too, with a 260mm front and 240mm rear wave disc, gripped by a two-piston caliper on the front and single-piston on the rear.
Finally, there’s more “red” in the side and front plastics than the current model, with new-look graphics for 2021, too.
Aiming For Aussie Impact
The 2021 Honda CRF450R reaches dealerships in October, so those that pre-ordered when the new model was announced in July will have their bikes soon. If you want to see one in the metal before you open your wallet, you’ll have to wait until November, due to supply delays from Japan. Either way, the 2021 model is priced at $12,899 RRP, which is a small increase on the 2020 version.
Honda Australia are confident the 2021 CRF450R will make a big impact in the local MX scene, so they’ve launched an all-new ‘Race Red’ rider support programme to celebrate its arrival. Honda Motorcycles’ GM, Tony Hinton, says the aim of the new Race Red initiative is to ensure opportunity is given to those looking to progress in both motocross and supercross.
“We have our Penrite Honda Factory Racing Team as a tier 1 level for National Supercross and MX classes. We’ve also got our ‘Ride Red’ programme for privateer riders competing in National and State events around the country and now we are proud to roll out a more refined ‘Race Red’ programme which looks to support riders at a local and dealer ambassador level of racing,” Hinton said.
“It’s the ideal time to launch the programme with our new CRF450R and 2021 MX line up, as we believe these bikes will deliver results to those who want to take the next step with their racing careers. We want to see future champions on our CRFs.”
Access to the program will be based on submission of an application via your local Honda dealer. Approved applicants will get access to racing Honda products and an affordable unit to race.
For more information on the 2021 Honda CRF450R and the Race Red programme, see your Honda dealer.
2021 Honda CRF450R Specifications
Type: Unicam four-valve four-stroke single
Bore x Stroke: 96.0 x 62.1mm
Compression Ratio: 13.5:1
Engine Start: Electric
Max Power: N/A
Max Torque: N/A
Clutch: Wet, multi-disc
Final Drive: Chain
Frame: Aluminium twin-spar
Front Suspension: Showa 49mm USD telescopic fork, compression/rebound adjustability, 273mm travel
Rear Suspension: Showa monoshock w/Pro-Link, compression/rebound/preload adjustability, 315mm travel
Fr Wheel: 21-inch
Rr Wheel: 19-inch
Fr Tyre: 80/100-21 Dunlop MX33
Rr Tyre: 120/80-19 Dunlop MX33
Front Brake: Single 260mm disc with twin-piston caliper
Rear Brake: Single 240mm disc, with single-piston caliper
LxWxH: 2,182 x 827 x 1,267mm
Rake: 27.7 degrees
Ground Clearance: 336mm
Seat height: 965mm
Kerb Weight: 110.6kg (wet)
Fuel Capacity: 6.3lt
PRICE: $12,899 RRP