Kawasaki’s KX450F Updated for 2018

New Fuel Map accessory | Retains air forks

Words: Jock McLauchlan Photos: Geoff Osborne

The 2018 Kawasaki KX450F is almost the same machine from last year, however the bike does offer some subtle updates to the suspension valving and the power characteristics thanks to a fuel mapping device. So where does this leave the KX450F?

Kawasaki offer a number of subtle updates on their 2018 model KX450F
Kawasaki offer a number of subtle updates on their 2018 model KX450F

I seem to be going on about this a lot at the moment, but the 2018 Kawasaki KX450F still has no electric start, and is now the only Japanese model to be running an air fork.

All new for this year, however, is an accessory hand-held fuel mapping device that can hold seven different options, along with the previous model’s three mode plugs.

The holeshot assist button remains, which works in first and second gears only and is designed to enhance acceleration while reducing wheel slippage.

The chassis is highly adjustable for rider fit with four-position handle bars across a 35mm range and the footpegs can go up and forward 5mm, or obviously, down and back 5mm.

The 2018 KX450F was tested at the Tarawera T100, a 100 mile trail event.
The 2018 KX450F was tested at the Tarawera T100, a 100 mile trail event

As part of the test appraisal for the KX450F, I rode the new bike in the Tarawera T100 and for a bit of background the Tarawera T100 is a 100 mile (160km) trail event that takes four hours to complete and offers an extreme testing ground.

I hadn’t ridden the T100 since 1991 (I think… it’s lost in the mists of time), and never at the new location. I also had never even started the KX until I warmed the machine up on the start line… so, it was in at the deep end, racing at its very best.

My memory of the old track was that it was either very fast or quite tight, and not so rough other than the usual choppy stuff and tree roots. With that in mind I had softened the rear shock two clicks and a quarter turn on compression, went two clicks quicker on rebound and moved the bars to the second most forward position because I’m tall – all of which was a mistake. The track was mainly third or fourth gear and MX-style ‘whoop’ rough, so the shock was way too soft for my size and the conditions.

The handlebars offer adjustable positions, ensuring rider comfort and control
The handlebars offer adjustable positions, ensuring rider comfort and control

Also, I felt less comfortable with the bars in that forward position. It gave a slightly over-centre feel in turns that required a reasonable amount of lock and felt odd, even though the extra room was appreciated when going straight.

One lap done I hit the pits and quickly adjusted the shock back to standard settings. Straight away it was a massive improvement. Now, with the shock riding higher in the stroke with more control and a heap more bottoming resistance, the whole machine felt better.

To me the shock feels a little softer than last year overall and very plush. Given that I’m over 100kg suited up, I think a younger/lighter racer would be very pleased with the shock’s action.

49mm Showa SFF-Air TAC forks offer good adjustability and 305mm of travel
49mm Showa SFF-Air TAC forks offer good adjustability and 305mm of travel

Up front the Showa SFF Air TAC fork is pretty plush and has decent bottoming resistance. They’re super adjustable and I found the action stable for the whole race. Air spring forks do feel a little different, in that air is more progressive in action than a spring… so they can be softer initially, but still man up enough for the big hits.

However the difficulty is getting the balance correct, where they’re riding high enough in the stroke and then not becoming too firm lower in the stroke… which I would say they were for the T100. Kawasaki has got them pretty much right as standard for the MX track, but I’m sure a little testing and tuning will pay off.

The suspension offers good adjustability, however finding the right balance with the air forks can be the challenge
The suspension offers good adjustability and stock MX capability, however finding the right balance with the air forks can be the challenge

After all, there are the inner and outer tubes, plus the balance chamber pressure to experiment with. Kawasaki recommends the air fork is bled and run at zero psi. Overall the suspension is a decent package and very adjustable.

The 450F chassis has a great balanced feel and I find the ergonomics excellent. It is one of the slower steering bikes in the class but it always feels planted yet accurate, and never gives the rider any ‘interesting’ surprises. I think it’s better in fast, open turns and berms but, don’t get me wrong, it can still turn tightly pretty well. As a handling package the KX450F is solid.

Bar controls include the engine stop button, but an electric starter is noticeably absent
Bar controls include the engine stop button, but an electric starter is noticeably absent

The engine has plug-in fuel maps for standard, hard and soft terrain (white, black, green respectively). Unfortunately, I was only given the standard (white) plug to try for this test, but it provided strong useable power right through the range, and there is serious thrust in the mid-range.

In the past I have liked the black plug most as it boosts torque and is less likely to detonate in deep sand under load, and I prefer to ride using the torque of the motor rather than the revs.

The 2018 KX450F features a 449cc liquid-cooled DOHC four-valve four-stroke single-cylinder with three engine fuel maps thanks to map plugs
The 2018 KX450F features a 449cc liquid-cooled DOHC four-valve four-stroke single-cylinder with three engine fuel maps thanks to map plugs

The power delivery is particularly smooth from idle and just above it, which is awesome where subtlety is required on slick conditions ,when trying to feel for every last bit of traction. However, that certainly does not mean it lacks responsiveness – when required it hauls. This is an easy to ride, tractable and fast engine.

What else? Well, the brakes are great, there’s plenty of power and feel there. The seat is a good flat shape with nice firm foam that doesn’t cause discomfort.

The 2018 KX450F's brakes offer good power and feel
The 2018 KX450F’s brakes offer good power and feel

The overall impression I’ve been left with of the the 2018 Kawasaki KX450F is of completeness. It is a well thought out, nicely put together and totally competent package. While it may not be outstanding in any one particular area, it doesn’t perform poorly anywhere either – making for an excellent machine in general.

The 2018 KX450F offers smooth throttle control, with tractable, fast power production
The 2018 KX450F offers smooth throttle control, with tractable, fast power production

The one thing it doesn’t have, but needs, is an electric start. Both Honda and Yamaha machines have electric start this year, as do KTM and Husky – so for this reason alone it is falling behind. That said, the KX450F is still a great bike.

The KX450F may not be oustanding in any particular area, but makes for an excellent machine in general.
The 2018 KX450F may not be outstanding in any particular area, but makes for an excellent machine in general.

2018 Kawasaki KX450F Strengths and Weaknesses

  • Plus – Smooth engine; adjustable chassis; great package.
  • Minus – No electric start; panel plastics seem a little brittle.

2018 Kawasaki KX450F
2018 Kawasaki KX450F

2018 Kawasaki KX450F Specifications

  • Engine Type – 449cc, liquid-cooled, DOHC four-valve, semi-dry sump, four-stroke single-cylinder
  • Power (claimed) – Not quoted
  • Torque (claimed) – Not quoted
  • Compression – 12.8:1
  • Bore x stroke – 96.0 x 62.1mm
  • Starting system – Kickstart
  • Fuel system – Fuel injection, Keihin 43mm body, dual injectors
  • Clutch – Wet, multi-plate, cable operated
  • Transmission: Five speed, chain drive
  • Frame – Aluminium, perimeter
  • Swingarm – Aluminium
  • Front Suspension – 49mm Showa SFF-Air TAC forks, preload, rebound and compression adjustable, 305mm travel front
  • Rear Suspension – Uni-Trak monoshock, preload, rebound and hi/lo-speed compression adjustable, 305mm travel rear
  • Brakes – 270mm petal disc, two-piston caliper front; 240mm disc, single-piston caliper rear
  • Wheels – Spoked, aluminium rims
  • Tyres – 80/100-21in front; 120/80-19in rear
  • DIMENSIONS
    • Wheelbase – 1495mm
    • Rake/Trail – 28.2°/126mm
    • Seat height – 950mm
  • Claimed weight – 108.8kg (wet)
  • Fuel tank capacity – 6.3 litres
  • Price – $11,599 (inc. GST)
  • Web – www.kawasaki.com.au

2018 Kawasaki KX450F
2018 Kawasaki KX450F

2018 Kawasaki KX450F
2018 Kawasaki KX450F

2018 Kawasaki KX450F
The 2018 Kawasaki KX450F’s seat is well padded

2018 Kawasaki KX450F
2018 Kawasaki KX450F