Yamaha’s latest WR450F doesn’t actually have a firework-style warning message on its handlebars, but thumbing the illuminated button on the left bar is the equivalent of lighting the blue touchpaper. In an instant the flexible, sweet-mannered enduro bike is transformed into an off-road rocket that responds to a tweak of throttle by launching its front wheel into the air and trying to tear its rider’s arms off.
As someone who’s ridden plenty of adventure bikes off-road but never competed on dirt, the idea of riding such a serious competition machine had seemed slightly outrageous, if not actually scary. Borrowing this latest WR450F from the Yamaha Off Road Experience (www.yamaha-offroad-experience.co.uk) showed that you don’t have to be an off-road expert to have plenty of fun on an open-class enduro bike.
The power button is just one of many changes to a WR450F that has been comprehensively updated for 2019. Its format is unchanged. A twin cam, four-valve single engine, whose cylinder head is reversed so the exhaust exits rearwards, is bolted into an aluminium frame derived from that of the YZ450F motocrosser.
Updates start with the engine, which has some tweaks to intake and exhaust systems that Yamaha claim add a few horsepower. Peak output isn’t quoted, as with most off-road bikes, but the WR makes around 55bhp. The five-speed gearbox (whose Wide Ratios, compared to the YZ450F’s box, give the WR its name) gets modified internals and a redesigned clutch that requires less lever effort.
The other engine-related change is the adjustable power delivery. The WR previously allowed tuning of its fuel-injection and ignition via an external Power Tuner. This is now incorporated into the bike and operated by a smartphone app, via Wi-Fi, while the new button allows instant swapping between two modes.
Chassis updates start with a revised aluminium frame, developed from the YZ450F, that is slightly slimmer and lighter than the old WR’s. Suspension was already serious off-road competition kit from KYB, with 310mm of front wheel travel and 318mm at the rear. The forks now get revised internals including longer springs; the shock has a lighter spring and larger oil reservoir for better cooling.
Bodywork is mostly new: slimmer, with the help of the new frame and more compact radiators, and featuring a lower headlamp surround and larger, 7.9-litre fuel tank. The seat is 20mm slimmer and also lower, though at 965mm it’s still mighty tall by most standards.
Compared to almost any adventure bike, the WR seems strikingly minimalist and light. There’s a tiny digital instrument panel and a few warning lights ahead of the wide handlebars, which give heaps of leverage. Unless you’re tall it’s a struggle to get a leg over the seat, but the suspension compresses helpfully once you’re aboard, and the light weight aids control at a standstill.
With no ignition key, starting it is easy – provided you do it right. Roll on a fraction of throttle before hitting the button (there’s no kickstart), and the WR barks instantly into life, hot or cold. But keep the throttle shut or open it too far, and the engine churns over without firing. This glitch was initially irritating but stopped being an issue once I’d learned the drill.
From then on the overriding impression was of how sweetly the Yamaha fuelled and how controllable it was with the softer B riding mode selected, which even multiple enduro champion Geraint Jones, who runs the Off Road Experience, said he’d have kept it like that on the muddy trails we rode on for much of the day. The flexible WR was happy to stay in third gear for most of the time, occasionally needing a tap down through the very clean-shifting box for tighter sections.
In B mode the Yamaha certainly wasn’t the scary-fast off-road weapon I’d imagined. It’s hard to know how much performance was cut (and that figure can be adjusted via the Power Tuner app anyway) but the big single didn’t feel notably more powerful than its similar looking WR250F sibling, which makes about 40bhp.
Performance was dramatically livelier after a press of that handlebar button. Throttle response was immediately thrillingly sharp, though still not at all snatchy as the Yamaha charged through the gears towards a top speed of about 90mph. The noise, mostly a slightly harsh induction sound coming from the airbox area behind the steering head, added to the feeling of speed but might get tiresome after a while.
Chassis performance was fantastic; a real eye-opener for me and good enough to impress some very capable off-road riders. Its 123kg wet weight figure means the WR is lighter than a large-capacity adventure bike by the weight of a typical pillion, which helped explain why it steered so effortlessly in response to pressure on the usefully serrated and widely-spaced footpegs.
The long range of superbly well-controlled suspension movement was a huge benefit too, allowing the Yam to float over obstacles or land controllably from jumps without bottoming. The small, wavy front and rear disc brakes were adequately powerful, and the test bike’s Dunlop motocross tyres gave even more grip than the Metzeler 6 Days enduro rubber that is standard fitment.
As a newcomer to open-class enduro bikes I got off the WR450F blown away not only by its speed and all-round performance but by how user-friendly it is. Better still, it doesn’t cost the earth. In fact at £7599 it’s only £400 more expensive than the WR250F and £450 cheaper than last year’s 450F. (As a competition bike it comes with a warranty for six instead of 24 months, and requires frequent servicing, with oil and filter changes every 1800 miles and valve clearances every 3000.)
The price cut is because the WR is no longer homologated for road use, so doesn’t come with parts including horn, mirrors and indicators that many buyers immediately removed. If you want to ride it on the road you’ll need to get a few of those bits fitted, and register the Yamaha with the DVLA as an enduro bike.
This involves some paperwork and expense, but Yamaha off-road dealers such as Manchester Xtreme (www.manchesterxtreme.com) or High Wycombe based Powerbiking (www.powerbiking.co.uk) can help, and reckon the process will add only a couple of hundred pounds to the WR’s cost. Which makes this latest big blue bruiser a tempting proposition – whether for serious enduro competition or merely for gentle greenlaning with the occasional burst of arm-yanking excitement.
Yamaha WR450F (2019)
|Engine type||Liquid-cooled single|
|Valve arrangement||DOHC, four valves|
|Bore x stroke||97 x 60.9mm|
|Carburation||Digital fuel injection|
|Maximum power||55bhp @ 9000rpm (approx.)|
|Front suspension||Usd telescopic, 310mm travel, adjustment for preload, compression and rebound damping|
|Rear suspension||Single shock, 318mm travel, adjustment for preload, compression and rebound damping|
|Front brake||Twin-piston caliper, 270mm petal disc|
|Rear brake||Single-piston caliper, 245mm petal disc|
|Front tyre||90/90 x 21in (Metzeler 6 Days Extreme)|
|Rear tyre||130/90 x 18in (Metzeler 6 Days Extreme)|
|Fuel capacity||7.9 litres|
|Kerb weight||123kg (full tank)|
Words: Roland Brown
Pictures: Double Red