Honda CRF450X Review 2005

Honda has finally responded to Yamaha and KTM’s sales onslaught in the high performance enduro bike category with the upcoming release of the new CRF450X.

Closely based on the very successful CRF450R motocrosser the enduro focused CRF450X benefits from electric start and improved cooling but the most important bit is the registration plate. ADR compliance finally allows Honda to finally go head to head with Yamaha’s big selling WR and KTM’s EXC range. The CRF450X is also still very much competition bred and like the Yamaha and KTM the Honda is certainly not intended for much road use but is designed to be ready to race pretty much straight out of the crate.

Racebike performance comes with racebike levels of maintenance. If racing the machine Honda recommends the piston and rings be changed every 15 hours but in the real world of trail riding with only some occasional full anger thrown into the mix you could probably extend that as far as 50 hours as long as you make your oil changes frequent.

Honda recommends oil changes every 1000km but personally I would be changing the engine oil every couple of rides as it is very cheap insurance. The oil and gearbox oil circuits are separated with 750ml of liquid gold in the engine and 650ml in the gearbox. Access to the oil filter is basic with an easy access cover on the left hand side of the engine requiring two 8mm bolts to be removed. The oil filters retail for around $12.50. Like I say, cheap insurance…

The cost of a piston change with all required parts and labour at full retail prices can come in at up to $600. Certainly not cheap and like the other racebike derived models you really need to judge how much use you think you will make of the bike and whether a softer option might be the go for you on that basis. These days 50 hours of riding is likely to be more than many riders will do in a year when you sit down and honestly add up how many chances you actually get to make it out in the dirt.

Access to the washable two-stage air filter is a tool free operation with a single clip release and a hinged airbox lid making things even simpler again.

The 449cc single is very similar to that found in the full monty ‘R’ motocrosser but the fitment of an electric start required new crankcases to be employed while the five speed box sports wider ratio gearing.

The biggest changes are to first and second gears with the ‘X’ scoring much shorter gearing. The final drive gearing is also shorter with a 51 tooth rear sprocket compared to the ‘R’ model’s 48 tooth item.

A taller fifth gear in the ‘X’ model offsets this somewhat at the top end but even so the ‘X’ will hit the rev-limiter at around 135kph in top. Another extremely welcome change for the ‘X’ model is the fitment of gears that are physically wider than those found in the ‘R’ model which bodes well for just how serious Honda have been in their development of the enduro variant.

No Content Available

The development continues through to the chassis. The frame is vastly different to that found on the ‘R’ model. At first glance it appears unchanged but closer study reveals that it is in fact an all new version fourth-generation twin-spar aluminium frame that forms the backbone of the CRF450X.

The lower frame rails have slightly thicker walls than the ‘R’, the steering head casting is all new and the jointing at the front of the frame also differs. New pivot plates bolt to both sides while the frame gussets have also changed in both shape and size. Finally the removable rear subframe is of a stronger new box section design.

All these changes were developed during a gruelling multi continent testing program that ran for 10 months with the aim of finding the best balance between rigidity and flex. As you would expect as an enduro bike is expected to cover terrain with a lot more variables than just the differences between motocross circuits.

I recently sampled a pre production version of the new CRF450X in a variety of terrain across mountain ranges stretching from the ACT into New South Wales. The first day was spent on a mixture of tight open terrain while the second was spent on an extremely tight and tricky enduro loop complete with some hair raising climbs and descents on some very rocky and challenging terrain. The CRF450X was untroubled by any challenge I could muster.

The steering is quite light and the bike reassuringly stable at speed although I am sure safari experts will be fitting an adjustable steering damper anyway.

For a particularly gnarly series of rocky outcrops littered with fallen logs I took some advice from Australian Safari expert Jamie Cunningham by backing off the front compression damping to the tune of six clicks, taking three clicks off the rear low speed compression and a full turn out of the high speed compression. This allowed the bike to shrug off the rocks and branches like they were hardly even there.

Like its smaller 250cc sibling the CRF450X suffers very little from wheel deflection no matter how much punishment is pushed through the dual-chamber inverted 47mm Showa forks. I find this one of the highlights of the ‘X’ models as it allows the rider to relax more which helps to better manage fatigue levels. It also allows those with meagre levels of skill in the dirt to negotiate terrain that on many other mounts would simply prove too challenging. In short, it can make a very average rider look quite good indeed and able to stay upright when otherwise they might be picking themselves up off the ground.

The forks are sublime and feature slightly stiffer springs than those found in the ‘R’ model (0.47kgf/mm v 0.46kgf/mm for those that have to know the specifics) to help compensate for the increase to a road ready 113kg dry weight. 314mm of travel is provided by the forks with 16 rebound damping settings complemented by 16 compression adjustments. Showa also provide the Pro Link rear shock which offers 17 rebound tweaks, 13 low speed compression settings and 3.5 turns of high speed compression adjustment. Enough to satisfy the most compulsive of knob twiddlers but here their time won’t be wasted as the changes can be clearly felt whilst riding.

Compared to the ‘R’ model the rear suspension on the CRF450X provides less of a rising rate progression and slightly less compression damping to help with compliance on the roughest of tracks while the shock piston is a beefy 50mm to help provide fade free performance.

Ground clearance is ample enough to clear just about any obstacle if employing correct technique.

In the engine room Honda engineers focused on making the machine tractable from idle through to the rev-limiter with the core focus on enhancing the already strong midrange. Don’t think for a minute all the top end has been sacrificed.

The machine still comes on cam fairly hard in the upper reaches of the digital tacho which very nearly caught me out a few times. The cylinder head and cam timing is also revised while more flywheel weight has been added to aid tractability. You certainly wouldn’t pick that last change. I would prefer even more weight added to the flywheel as a lot of clutch slip is required to keep the machine from stalling in tricky situations.

The changes to the cam timing sees the ‘X’ model’s intake valve open 5° later than the ‘R’ and closes 5° earlier. Similarly the exhaust valve opens 5° later but closes at the same time as that found on the ‘R’. The valves themselves are slightly smaller with the titanium intake valves 1mm smaller on the ‘X’ (35mm v 36mm) while the steel exhaust valves are also 1mm smaller at the face and are made from a new heat-resistant steel alloy. Honda does not have a recommended replacement schedule for the valves but states that clearance should be checked every 1000km.

The ultra short two-ring forged piston found on the ‘R’ model is carried over to the ‘X’ but benefits from an oil jet spray directed to the underside of the piston. Other changes include tougher big-end and main bearings with added thrust washers on the crank to further enhance reliability.

The intake plumbing has been revised to increase the intake velocity to further enhance low speed throttle response and boost midrange grunt. This feeds the very trick Keihin 40mm flat-slide carburettor which is carried across from the ‘R’ model while on the exhaust side of the equation a longer pipe with a smaller internal diameter (38.1mm v 41mm) serves to boost the midrange even further. Amazingly Honda state that the CRF450X will run fine on standard unleaded and that their no real need for the use of premium fuel.

The motor is remarkably smooth and is free of the annoying vibrations found on most European equipment and also produces less vibes than comparable Japanese machinery.

One feature the ‘R’ model doesn’t have is the new electric starter developed for the ‘X’. A kick start back up is provided and is sometimes needed to be called upon however I never needed to use the hot-start lever in order to fire the beast into life and instead relied on the automatic decompression system to lighten the starting load. The fitment of the electric start has meant widening the cases but this has been kept to a hardly noticeable 17mm increase thanks to a thinner clutch pressure plate helping to offset some of the increase.

Another side effect of the move to electric start has been the removal of the oil sight window which would have been obscured by the larger generator required to power the ADR lights and stronger 48 watt charging system so instead the machine is fitted with a dipstick. The generator does seem to provide quite reasonable power as the sturdy 35-watt halogen headlight does not fade and glow brighter as the revs fall as is so evident on many European built machines. The tail light is a low draw LED inside what looks like a regular style housing which makes it look as though it is a conventional bulb inside but it is in fact and LCD.

Some clever thinking has gone into the cooling system with the system running at a reduced pressure to aid durability in the long term while the actual cooling capacity has been increased by 10%. A catch tank is now located out of the way behind the front skid plate. One rider did manage to hole the clutch cover with a rock and a larger purpose built plate would be a wise fitment for serious bush bashers. The radiators seem reasonably well protected by the shrouds but again it would be wise to fit some aftermarket radiator guards as cheap insurance.

Honda have been very smart to fit the machine with a convenient charging plug and have been generous enough to include a trickle charger with the machine in order to keep the battery in optimum condition between rides. The charger plug is fused, has a plastic cover protecting the terminals and hides behind the left side cover ready for easy access by hand. This is good thinking and something that they could even consider carrying over to some of their road models as it would benefit the riders who can only get out and about on two wheels once in a while.

The larger 8.6 litre fuel tank, compared to the 7.2 litre tank on the R, that proves enough for well over 100km of trail riding at virtually any speed and incorporates a useful 1.4 litre reserve. A sidestand is also fitted and Honda exhibit their attention to detail once again here with the stand mounting point integrated into the rear of the left peg bracket. This means that the stand and its mount can easily be removed for racing by simply exchanging the left peg bracket for a CRF450R item.

240mm discs grace both ends of the machine and do the job with no fuss. Front brake feel could perhaps have been marginally better but on reflection that could also have been my fatigue levels affecting my own ability to finely control the available braking power.

The rear brake is outstanding with a lovely progressive action allowing for perfect control. I did manage to produce a tiny bit of fade after a ridiculously long series of descents and tricky terrain but I can’t imagine many riders ever encountering similar conditions and am sure it will never pose a problem.

Rider comfort has also come in for a cursory glance of attention with a wider seat than that found on the motocrosser which also benefits from more rounded edges for longer days in the saddle. These points combined with the multiple density seat foam makes it much less of a plank than that found on comparable machines and the cover offers good grip and durability.

Moving around on the machine is a smooth affair with no sharp edges to tug at your riding gear and the slim profile means it is easy to put your weight where it’s needed for any given situation.

The machine features rubber mounted adjustable reach Renthal (971 bend – same as R model) bars, which also host a quick adjust clutch perch which can be tweaked while on the fly. The brake lever is also span adjustable.

The pegs offer great grip and are nice and wide. They are quite short in keeping with the race theme and this helps the rider to stay close to the centreline and grip the bike between the knees better.

The rear rim is 1” smaller than the motocrosser for better protection from punctures. Michelin AC10 tyres offer plenty of grip while being ADR legal and can be reversed for longer life. They also wore amazingly well and I saw no evidence of knobs tearing or slicing which was quite amazing considering the terrain we traversed.

The digital instrumentation is no simple afterthought with a large easy to read digital speed readout complemented by extra insets which are selectable for trip meters, an hour meter and a clock. A bar style tacho graces the extreme left and upper reaches of the LCD display and serves more as novelty value than any real useful purpose. However I’m sure some riders will appreciate it and it is a nice touch. Included in the spares kit is the original USA specification odometer in miles so for those that plan on crashing a lot it could be a wise idea to fit this unit when you are not going to require the full functions of the LCD display.

As delivered the CRF450X has a baffle bolted to the end of the muffler which when removed does not make the bike too offensively loud and in order to fully unleash the potential of the beast a throttle stop also has to be removed from the 40mm flat-slide carb. This is only intended for race use however and it is unlikely that many Honda dealers will be keen to help you if you do not show them a race licence as evidence that the machine will be used for racing rather than on the road.

All the parts that have been removed and replaced for the ADR conversion for registration also come with the bike and that includes the non ADR headlight and shroud, kill switch, starter switch, odometer, Dunlop D756 tyres, original throttle stop pin and front brake master cylinder and lever. So effectively you have some race only plastics and a spare set of tyres thrown in to boot!

Unfortunately there is no off the shelf supermoto kit expected from Honda at any near stage so those wanting to go down that route will have to source third party aftermarket components if converting the machine for supermoto competition. Do remember when choosing rims to try and obtain a rear rim that is cush drive dampened as this greatly reduces the loads placed on the gearbox with sticky road rubber and aggressive use. This advice should be heeded for all motocross based bikes being converted to supermoto specification as it is just as relevant to all of them.

Honda’s eagerly awaited CRF450X is expected to land in dealer showrooms soon and like the WR Yamaha and EXC KTM models the Honda is a racebike first and foremost. If you plan to do many kilometres on the street then one would be wise to plump for a softer option. For the hard core fraternity Honda’s CRF450X is an extremely well sorted and user friendly mount with enough performance in reserve to satisfy the most demanding of riders. It gives every indication of being a very well sorted and refined beast with high quality components throughout including the durability of the plastics and stickers. The fasteners also appear to be quality items.

Honda has thoroughly tested the machines across many countries and virtually every possible form of terrain to come up with what is effectively a whole new model. They have not just whacked on some lights and a quieter exhaust. The whole machine has essentially changed from the ground up to suit its new role as an enduro mount and it has the performance to take on anything while also being more user friendly and vibe free than anything comparable on the market. This certainly adds a lot to the riding experience for me and will surely be welcomed by any trail rider as this really does affect how quickly the rider fatigues and remains comfortable.

The CRF450X is an extremely polished package with the piston replacement schedule perhaps the only drawback with the model. But that’s the price you pay for premium performance and here in Australia we are lucky to get the machine ADR approved with a number plate on the back which makes riding the machine legal virtually anywhere vehicles are allowed to tread. Australia is the only country to have this model road registered and for that we do really deserve the well worn ‘Lucky Country’ tag.

SPECS – Honda CRF450X

Engine: 449cc, Liquid-cooled four-stroke Unicam four-valve single
Bore x Stroke: 96 x 62mm
Compression: 12.0:1
Induction: Keihin 40mm flat-slide
Starter: Electric & Kick
Transmission: Five speed (wide ratio)
Final Drive: Chain (520 T-Ring)
Wheelbase: 1,480mm
Dimensions (L x W x H): 2,175 X 860 X 1210mm
Trail / Rake: 110.3mm / 27.25°
Ground Clearance: 348mm
Seat Height: 962mm
Dry Weight: 113kg
Fuel Capacity: 8.6 litres
Tyres: Front _ 80/100-21; Rear _ 110/100-18
Suspension: Front _ Inverted fully adjustable 47mm Showa cartridge forks with 314mm of travel (16 rebound settings, 16 compression); Rear _ Fully adjustable Pro Link Showa single shock with 312mm of travel (17 rebound settings, 13 low speed compression settings and 3.5 turns of high speed compression adjustment)
Brakes: Front _ 240mm single disc, twin-piston caliper; Rear _ 240mm single disc
Price: $11990 + on road costs
Warranty: Three months (parts only)
Available: Soon