2019 Husqvarna FS 450 Review – First Ride

Troy Siahaan
by Troy Siahaan

The joy and fun of riding supermoto is something I personally love, but apparently this sentiment isn’t shared by most. It’s too bad, really. Supermoto offers all the fun of track riding for a fraction of the cost of taking your sportbike to a trackday. And if you’re a dirt guy, there’s even some of that, too. By their very nature, motocrossers are light, narrow, agile, and come packed with potent engines. Converting them into SuMos isn’t more than a wheel change, brake swap, and suspension tweak away, and yet the apparent demand is so small most OEMs – with the exception of Suzuki and its DR-Z400SM – haven’t taken notice.

2019 Husqvarna FS 450

Editor Score: 90.5%
Engine 19.0/20
Suspension/Handling 13.0/15
Transmission/Clutch 9.0/10
Brakes 8.5/10
Ergonomics/Comfort 8.5/10
Appearance/Quality 9.5/10
Desirability 9.5/10
Value 9.5/10
Overall Score90.5/100

Emphasis on most. Thankfully, Husqvarna hasn’t forgotten about us and has graced us with the FS450 supermoto. Based on the FC450 motocrosser, the FS450 is updated compared to last year’s version. A stiffened frame claims to enhance rider feedback – and it’s blue because, well, Husqvarna. A feature unique to Husky, the revised (versus last year) two-piece carbon fiber composite subframe gets a further weight reduction, down 0.6 lbs, making it just over 1 kg, or 2.2 lbs. In all, Husky says the FS450 weighs a mere 227 lbs, minus gas – just four pounds heavier than the FC450 MXer.

In the MX world of a few years ago, air forks used to be all the rage, wherein the traditional coil springs were replaced with a pneumatic cartridge. On paper there were a few benefits. First, trading springs for air meant a significant weight reduction. Second, adjustments for rider weight or riding style can be made by either adding or subtracting air, whereas before you’d have to change physical springs.

The reality, or at least so I’m told by my MX friends, was that air springs became really finicky to master. A perfect setup one moto could feel terrible the next. Temperature played a big role in the air fork’s behavior, as does sealing of the system; air expands and contracts depending on its temperature, while a little bit of air leaking out can both wreak havoc on a setup. Surprisingly, the FS450 still wears WP’s 48mm AER fork (and DCC rear shock). Both get revised settings for SuMo use and are fully adjustable.

Behold the Husqvarna FS450. If it had lights, blinkers, and a license plate it’d be a one-way ride straight to jail. But oh what a ride it would be…

The most obvious difference between a MX and SuMo is the wheel, tire, and brake package. Traditionally, folks who convert a motocrosser to supermoto either re-lace the stock hubs or buy aftermarket versions. Either way the wheel size is 17 inches, mostly because there’s a huge range of tire options. As we’ve learned from the usage of the AER fork, however, Husqvarna does things a little differently. Instead, the FS450 gets Alpina tubeless wheels measuring 17 inches in the rear, but 16.5 inches up front. In theory, the smaller diameter front wheel will help with turn-in and help the FS with its agility. The downside is rubber is harder to find. However, finding good rubber is not impossible, and the standard 125/80-16.5 front, 165/65-17 rear Bridgestone Battlax Racing slicks are excellent. Stopping the 227-lb FS450 comes down to a 310mm disc and Brembo four-piston radial-mount caliper in front, and a 220mm disc with single-piston caliper in the back. A radial master cylinder and steel-braided lines round out the package.

Saving the best for last, the FS450 gets a revised 450cc Single compared to last year, with a focus on making things lighter and more compact. To that end, Husqvarna redesigned the SOHC cylinder head, making it more compact and lighter, moving the camshaft closer to the bike’s CoG. Overall, the engine is 15mm lower compared to its predecessor and sheds slightly more than one pound, too – not bad when talking about a little 450cc Single. Slightly revised valve timing delivers more bottom end. When it’s all added up, Husqvarna claims the FS450 puts out 63 hp at the crank. Impressive. What’s more impressive is the fact that factory racebikes in Supercross are putting that much power to the wheel.

A powerhouse of an engine, getting 60-plus horses out of this 450cc Single is mighty impressive. Some tweaks for 2019 mean it’s more compact than before.

With that kind of performance on such a light racing machine, taming it all is important. Because of this, the FS sees technologies formerly reserved for sportbikes, like adjustable engine mapping, launch control, and traction control. There are two engine maps, and traction control (which can be turned off) is also correlated to each map. The TC system itself doesn’t employ wheel speed sensors, but instead uses a more crude system that analyzes engine speed and its rate of change (similar to early iterations of TC from MV Agusta). Should that rate of change exceed the predetermined algorithm depending on the gear, power mode, or both, ignition timing will be throttled back to help the tire get traction again. Getting drive out of corners is great, but SuMo is all about letting the rear hang loose and sliding it into a corner. To that end, a Suter slipper clutch helps a ton in keeping the back wheel settled while banging downshifts and kicking the rear out.

Excited yet? You should be, and for $10,799 it’s much easier (and likely cheaper) to simply buy one of these instead of converting a ‘crosser. But like all good things worth having, there’s a catch: we’ve been told only about 200 FS450s are coming stateside. So if you haven’t already spoken up for one, you might already be too late. Luckily for us, we were able to snatch this example.

We’re entering a new dawn with dirtbikes when you start to find traction control and engine map buttons on the bar. On the other side lies the starter button. There is no key – so make sure you have somewhere safe to store the FS when not in use.

You snooze, you lose

It’s a strange thing, trying to evaluate the FS450, because by default it’s the best motorcycle in a class of one. Nonetheless, the FS is an absolute riot for ripping up your local kart/supermoto track. The first thing you notice is the lack of a key – this is a racebike after all. Make sure you’re in neutral, push the starter button and the raucous 450 Single lights up (and yes, it will jump if you try starting it in gear). Our particular tester was equipped with an accessory FMF exhaust, giving a particularly healthy note at each crack of the throttle.

Once out on track it’s instantly clear the FS450 isn’t a bike for beginners. Throttle delivery is crisp and unforgiving for the inexperienced. It leaps at the first call, leaving no doubt about the bottom end power from the 450 Single. Of course, this was on Power Mode 1. Switch to the second map and things lighten up a little when you turn the throttle, but the word “soft” doesn’t belong anywhere near the FS450. Lofting up power wheelies in either mode in the first couple gears is only a clutch pop and wrist flick away.

I’m terrible at wheelies, but the FS450 makes them look easy.

Power from the bottom and mid range is healthy, with a slight tapering on top, but rowing through the five gear ratios takes just a flick from the toe. The gears are closely-spaced, since supermoto tracks are shorter and tighter than traditional roadrace tracks, which means you’ll find yourself shifting often, though the FS does have decent overrev should you need to carry a gear just a tiny bit longer than you should.

As mentioned before, the Bridgestone slicks offer up all kinds of grip, and I really don’t think I got them spinning enough to engage the traction control. Judging by experience, intervention from rate-of-change traction control systems is fairly obvious, and the Husky never intruded on my fun.

Nicky Hayden proved you can ride supermoto with your knee on the ground.

Of course, the real fun of supermoto is hitting the brakes, clicking downshifts, and wagging the rear loose. To this end, the Brembo components gave excellent stopping power and feel – though a very minor argument could be made for a smidge more bite from the pads. Still, the brakes are by no means inadequate, and if you do it right, tapping the rear to initiate a slide while downshifting can make even the biggest squid a hero for a second or two. Get it wrong (which is also easy to do) and you just end up looking like a bigger squid.

Slick tires, wide handlebars, and virtually no weight make for the perfect trifecta when it comes to slicing corners, and the FS450 inspires confidence. Despite the fact many MX guys have gone back to coil springs in their forks, there wasn’t much to complain about with the WP AER fork. Once the initial air pressure was set in the morning, it provided excellent support and compliance all day, with hardly a compression or rebound tweak needed all day. Leaned over, both the fork and shock simply absorbed bumps and gave just the right amount of feedback.

The FS450 corners with the best of them, but I half expected it to flick over quicker.

If I did have one gripe, transitions side-to-side on the FS weren’t as quick as I expected them to be despite the 16.5-inch front wheel. They weren’t slow, mind you, but I expected such a focused machine to have lightning fast reflexes. Then, I compared some numbers:

Husqvarna FS450Yamaha YZF-R6KTM 790 Duke
Rake: 26.1°Rake: 24°Rake: 24°
Trail: NATrail: 3.8 in.Trail: 3.8 in.
Wheelbase: 58 in.Wheelbase: 54.1 in.Wheelbase: 58.0 in.

With its less aggressive rake and long-ish wheelbase (compared to an R6), the slower transitions made more sense. The FS relies on its light weight for agility and wide bars for leverage; Be deliberate with direction changes and the FS responds in kind.

Still, don’t mistake this as the Husqvarna FS450 being anything short of a weapon. I’m confident the it could show up at a supermoto race and surprise a few people on their built machines. Heck, with the right rider it stands a strong chance of stepping on a podium. It’s a shame there will only be a limited number of these coming here, but even if you can’t get on one, you owe it to yourself to give supermoto a try. If you do it might convince Husqvarna to bring in more, and I think the world could use some more supermotos.

2019 Husqvarna FS 450

+ Highs

  • Impressive power
  • Strong brakes
  • Lots of bike for the money

– Sighs

  • Wouldn’t mind a little faster turn-in
  • Super limited quantities
  • Not street legal (maybe that’s a good thing?)

2019 Husqvarna FS 450 Specifications

Engine Type4-stroke Single, with four valves / SOHC with rocker levers
Displacement449.9 cc
Bore x Stroke95 mm x 63.4 mm
Compression Ratio12.75:1
StarterElectric starter with lithium ion 12V 2.0Ah battery
ClutchSuter slipper clutch, Magura Hydraulics
EMSKeihin EFI, throttle body 44 mm
FrameCentral double-cradle-type 25CrMo4 steel, Carbon fiber reinforced polyamide subframe
HandlebarPro Taper, Aluminum Ø 28/22 mm
Front SuspensionWP inverted fork, AER 48, Ø 48 mm, 11.0 inches of travel
Rear SuspensionWP shock absorber with linkage, 10.5 inches of travel
Front Brake310 mm disc brake, four-piston radially-mounted Brembo caliper
Rear Brake220 mm disc brake, single-piston Brembo caliper
Front Wheel3.50 x 16.5″ Alpina black, aluminum/
Rear Wheel5.00 x 17″ Alpina black, aluminum
Front Tire125/80-16.5″;
Rear Tire165/65-17″
Chain5/8 x 1/4″
Wheelbase58 ± 0.4 inches
Ground Clearance11.4 inches
Seat Height35.0 inches
Tank Capacity1.85 gallons
Weight Without Fuel227 pounds (claimed)
Troy Siahaan
Troy Siahaan

Troy's been riding motorcycles and writing about them since 2006, getting his start at Rider Magazine. From there, he moved to Sport Rider Magazine before finally landing at Motorcycle.com in 2011. A lifelong gearhead who didn't fully immerse himself in motorcycles until his teenage years, Troy's interests have always been in technology, performance, and going fast. Naturally, racing was the perfect avenue to combine all three. Troy has been racing nearly as long as he's been riding and has competed at the AMA national level. He's also won multiple club races throughout the country, culminating in a Utah Sport Bike Association championship in 2011. He has been invited as a guest instructor for the Yamaha Champions Riding School, and when he's not out riding, he's either wrenching on bikes or watching MotoGP.

More by Troy Siahaan

Join the conversation
26 of 29 comments
  • Sayyed Bashir Sayyed Bashir on Dec 14, 2018

    I can't understand why it isn't street legal. I thought most supermotos are ridden on the street, for commuting etc. as a general purpose bike. Making it track-only limits its usefulness. $11K is a rather large chunk of money for a hobby bike. We don't just need more supermoto riders, we need a street legal supermoto bike.

    • See 22 previous
    • TroySiahaan TroySiahaan on Dec 19, 2018

      Now you've done it. Expect some spam mail soon...

  • Gjw1992 Gjw1992 on Dec 15, 2018

    Worth checking out RJ's utube vids of his 300exc tpi - now effectively a 300 SM. Nice tour of London's xmas lights posted recently.

    • Spiff Spiff on Dec 15, 2018

      Lamb Chop did a 500 KTM conversion as well.