5000 MILE TEST
You could dismiss Kawasaki’s Z900RS as nothing more than a hasty retro makeover. But this naked is much more than a packaging exercise. It’s a great ride, comfortable and economic too. But is it tough enough to tackle a decent mileage?
Kawasaki’s Z900RS steps up to the toughest test in motorcycling.
TWO LETTERS SEPARATE THE RS from its sibling – Kawasaki’s Z900. Two letters and a huge amount of effort. Certainly this is no hasty reboot like, say, Yamaha’s XSR reimagining of their wildly successful MT-09. No, the development of the RS involved a fundamental engine and chassis overhaul, resulting in a wholly different motorcycle. Ride the RS alongside the Z900 and the changes feel considerable. You sit on the bike, rather than inside it. The raised handlebar suits upright riding and thrust is easier to access. It’s a much better road bike. But there’s more to the retro market than the XSR. The RS must fend off threats from twins such as Triumph’s 1200cc Thruxton, V-twins like Ducati’s Scrambler 1100 and boxers like BMW’S R ninet. Can an inline four deliver character to compete with this level of competition?
Engine and transmission
‘The First thing you notice is there’s power all the way from the bottom end up,’ says art editor Paul Lang, and he’s ridden the Kawasaki a lot. ‘It feels almost like it’s powered by a torquey triple engine. But it’s an inline four. ‘The second thing you notice is how bad the throttle response is. There’s a halting on-off feel to the fuelling at small throttle openings, which would be frustrating on its own. But twist harder and the bike surges forward alarmingly.’ This surging is most noticeable in first gear. Watch any rider set off for the first time and they’ll be caught out by the neck-straining pull to 30mph. Then they’ll shut the throttle and be caught out by the cleaver-like chop in fuel. The effect is much stronger than on other 2018 Euro4compliant bikes, such as KTM’S 790 Duke. There’s no such surging on the donor bike either which employs the same engine as the RS – 948cc liquidcooled 16-valver. However, the RS trades a claimed 15.5bhp from peak power in exchange for fat gobs of midrange thrust. Inside the casings there’s a heavier flywheel and crank, revised cam profiles and a larger balancer shaft to counteract the increase in vibration. Shorter gears pull the power into more usable territory which makes for a ramp of torque between 5000 and 6000rpm and peak torque – 68.4 lb.ft – at 6750rpm. All this makes the RS a much better road bike than the Z900, despite the fuelling problems. There’s vivid acceleration in the first three gears and punchy overtaking potential in sixth. Brilliant fun, if a tad vibey at the handlebar. Mr Lang guided the RS around Rockingham Motor Speedway’s national circuit on two of Bike’s 2018 trackdays and submitted glowing reports eulogizing about gutsy midrange, a light clutch and a short-throw gear lever. All of which make for satisfyingly quick gear changes. The airbox roars pleasingly and the stock exhaust surprises with a pop on the overrun. After two trackdays and 5000 miles the 900’s oil level still reads just a touch below full. ‘But the gearbox is getting notchier,’ complains Langy. ‘There’s no quickshifter or autoblipper, so I clutchless shift to save time. It’s easy in second, third, and fourth, but sometimes I miss sixth and roar into a false-neutral freewheel. That’s unnerving.’ Turns out tightening up the chain clears up transmission issues and smooths out shifting between the bigger ratios. In a market full of boxers, twins and triples choosing an inline four might seem like a bland choice. But Paul disagrees. ‘Buying a four-cylinder bike is an easy choice. I don’t need the faff of wrestling the torque reaction of a BMW boxer, or the bother of riding around the lumpy power band of, say, a Husqvarna 701 Supermoto. The Kawasaki’s four means I can ride in comfort and enjoy my surroundings. It’s the sensible, engaging, choice.’
Handling and ride
‘There’s no damping in that fork,’ announces a K-tech technician at the company’s Leicestershire headquarters. Paul’ s taken the RS to upgrade the stock suspension. The original rear shock (adjustable preload and rebound) is replaced by a K-tech Razor-r (£495) and the front stanchions re-valved. A remote preload adjuster comes in handy on a bike used for occasional pillion carrying – pity you need C-spanners to adjust the stock unit. The ‘no fork damping’ revelation makes sense: as standard, the RS fork dances over the slightest road surface imperfection. The fork springs compress over bumps and rebound immediately, pogo-ing the headstock and hurting confidence in the front end. The stock shock balances the front in spring rate, and new bikes editor John Westlake reports bouncy-yet-balanced performance at Rockingham. But ride slower over bumpy ground and the experience is far from balanced. K-tech assess the stanchion springs are of good quality and leave them alone. They replace the valves and add their own fork oil. The result is significant. Suddenly the RS is tracking ground better. You feel as if the front tyre is constantly in contact with tarmac, consequently steering inputs are more secure and corners are rounded without front-end chatter. There’s also a pleasing kerpluff as the fork oil is squeezed through the new valves. The total price for this overhaul? £900. ‘It’s worth every penny,’ announces Paul without hesitation. ‘I didn’t think it would be, but the change is remarkable. It holds its line better, soaks up bumps like never before, and still works with the added weight of a pillion. Now the chassis feels good enough to make the most of that engine and the strong, progressive brakes. I can’t emphasise enough how much better the bike is to ride now.’
An LCD display nestles between the historically-appropriate double bullet clocks. It’s filled with important information, like a useful gear indicator, a six-level fuel gauge, range and odometer readings,
and a digital clock. The acronym for Kawasaki Traction Control sits just above the gear indicator. There are two settings plus off, selected using the rocker on the left switchgear. Modes are simple to understand: two is high intervention, one allows front wheel elevation. ABS isn’t switchable, but doesn’t interfere with Paul’s or John’s Rockingham track antics. There are no riding modes or other faffery, but what is present is quality kit.
Controls and comfort
It’s pleasing to see a three-way relationship that works. Seat, footpeg, and handlebar locations create comfortably upright ergonomics. The chrome handlebar sweeps up towards you, and circular mirrors sit on long stalks so you look over your elbows instead of at them. In Bike’s August issue group test the Z900RS impressed with better rear views than Ducati’s Scrambler 1100, Yamaha’s XSR900 and BMW’S R ninet. ‘It’s very easy to ride long distance,’ says Langy. ‘The seat’s so plush you can go for hours without aching. I’ve ridden it down to the Ace Café, and good old Swindon, and haven’t felt any pain at journey’s end.’
It’s a naked motorcycle. Rain will drench you. Wind will batter you. But it’s a great machine for night riding. Lighting is universally LED, with a strong headlight and useful high-beam spread. Paul continues to commute on the Z900RS as daylight hours diminish, despite the presence of an uber-capable Yamaha Super Ténéré in the Bike lock-up. ‘I love the brake light,’ he announces. ‘The light source is LED, but plastic surrounds make the spread of light look like a proper bulb. So it’s bright, but still reminds of the old Z1. That’s stunning attention to detail.’ The brake light isn’t the only place Kawasaki R&D have focussed their efforts. One-piece wheels look like they’re spoked, but aren’t anywhere near as much of a faff to clean. The pillion perch is as comfortable as the rider’s accommodation. Bungee hooks are standard fitment, and screw onto the subframe. And the battery is located just under the seat. Installing chargers or heated kit power cables is as easy as removing the bench and unscrewing two bolts. The teardrop tank doesn’t just look large, either. It holds 17 litres of fuel, which typically lasts just under 200 miles. Hold a constant 80mph on the motorway, though, and the low fuel warning light winks on at 165 miles. That means cruising economy is an impressive 61.9mpg. If you are a dry-weather-only rider the Z900RS has all the practical touches you’d ever want.
‘This is no hasty reboot… the creation of the RS involved a fundamental engine and chassis overhaul…’
Quality and finish
This is where the RS builds up most of its character. From the seat to the bullet clocks and ducktail fairing, the finish is undeniably well thought-out. Nods to the Z1 come in all shapes and sizes, from the crosshead screws holding on the clock faces, to laser-cut half-moon camshaft end covers. In fact, the single design disappointment is the box-section swingarm, thankfully hidden by black paint and the bright chrome exhaust. ‘Ooh, ain’t it gorgeous,’ coos Paul when I ask him about the paintwork. The colour is Candytone Brown/candytone Orange, the most expensive finish available for the RS. It’s £100 more than the matt green, and £300 over the base black. But the majority of Bike staffers believe it’s worth the money. Paul again: ‘I want to point out the ‘Z’ they’ve painted on the front of the tank. Lovely touch, that. No matter individual taste, the quality of the paint is universally applauded. Elsewhere, the finish is showing signs of wear. Take the ‘Kawasaki’ tank badges and ‘Z900RS’ subframe badges. Both are losing paint. Don’t expect the accessory full-caps ‘KAWASAKI’ tank logos to be better, even though they cost £79 per pair.
It took an expensive suspension revision to sort out the ride
Stylish urban-ism. And Langy
Summer in Birmingham – there’s nothing quite like it
Contemporary brightness with a whi of the original Z
Some of the details are starting to show signs of wear
Not the most aerodynamic pairing