Americans love big engines, especially when they make lots of power. Maybe it’s something to do with their many miles of straight roads, a culture of drag racing, or perhaps they simply enjoy showing off?
Whatever the case, there´s no doubt that a course of therapy should be mandatory for anyone who finds the 175mph ZZR1100 too slow for normal use, and therefore sticks a turbo-charger onto it. Then again, maybe turbo powered motorcycles are the best therapy money can buy?
At about 6000rpm and 80mph in fourth gear, a flick of the throttle is enough to lift the front wheel and send the bike hurtling forward with its only audible sound an evil induction hiss from below the tank. The Kawasaki picks up speed so fast that almost immediately you snap into fifth, and the handlebars go light as the horizon tries to wrap itself round your bulging eyeballs.
Into top and the ZZ-R hisses again, still accelerating with mindwarping ferocity. Suddenly the three-lane road seems incredibly narrow; there´s traffic ahead doing 100mph in reverse. Hold it flat-out for a few seconds more, then back off – looking down to see the speedo needle coming back down through 165mph as your heart pounds away at some stratospheric rate of its own.
Gradually the adrenaline subsides as you pick your way through the traffic, wondering if perhaps you imagined the whole thing. The boost gauge´s tell-tale needle is indicating a maximum of 19psi, so there must have been a lot of horsepower at the end of the throttle wire. But still the experience of full-bore acceleration on Mr Turbo´s ZZ-R1100 is a little difficult to believe.
No wonder. This machine is very probably the fastest roadgoing motorcycle in the world, having been radar-trapped at 215mph by the American magazine Motorcyclist. Terry Kizer, Mr Turbo´s boss and one of the world´s leading top-fuel drag-racers, estimates its maximum power output at between 270 and 300bhp, compared to the 120bhp of the standard ZZ-R1100, and says it has the potential to go considerably faster still.
Kizer´s credentials for producing the world´s fastest streetbike are impeccable. Nine times an American champion, the little man from Houston in Texas knows what it´s like to ride a 650bhp bike to a standing quarter-mile in 6.82 seconds at 199.97mph. He has been involved with turbocharging for over a decade, working on research and development for Mr Turbo before taking over the company three years ago.
This ZZ-R kit is significant partly because of the Kawasaki´s unprecedented speed straight out of the crate, but also because this is Mr Turbo´s first application to use fuel-injection. Previous kits (there are over a dozen, for bikes including most big Kawas and Suzukis, plus Honda´s CBX1000 and Yamaha FJs) use a single carburettor. But for the ZZ-R, Kizer enlisted the help of Californian specialists Martronic Engineering to develop an injection system that will soon be modified to fit the other models too.
The work took two years, and there´s little in the ZZ-R´s near-standard appearance to show for it. Apart from the paint job, fairing-mounted boost gauge and four-into-one pipe it is hard to tell that this bike is anything out of the ordinary. Beneath the bodywork, though, a fat hose leads down from the ram-air intake slot to a Rayjay FF40 turbocharger that is just visible through the mesh at the front of the fairing. The four exhaust downpipes converge before entering the other side of the turbo, exhaust gas leaving via a single pipe that runs along the right side of the bike to a Vance & Hines silencer.
Another big silver pipe leads from the turbo, up the front of the engine and then back over its top to curl round into a neat billet-alloy chamber, fitted with a row of injectors, that sits beneath the stock fuel tank. The fuel-injection system reads only manifold pressure and engine speed (‘It´s as simple a system as you´ll see,´ says Kizer), and can be fine-tuned by turning screws on the alloy control box under the seat.
The system is pressurised by a Bosch car pump, and it is by adjusting this, as well as using the wastegate, that Kizer regulates the turbo´s output. For top-speed runs the pump can be set to deliver 70psi, but normal pressure is 50psi – good for 15 to 20psi of boost and an estimated 250bhp. An internally standard engine using pump fuel is okay for up to 10psi of boost, giving an output of 160 to 180bhp. Above that, precautions are necessary.
Hence the small chamber near the ZZ-R´s rear numberplate, which holds a 50:50 mix of water and methanol. With the system turned on, the chamber is pressurised. Boost of 5psi triggers a switch to inject water into the turbo, where it joins the fuel mixture to cool the combustion chamber and reduce detonation. ‘We´re using racing gas today, so the water injection is not necessary, but we use both on top-speed runs as an insurance policy,´ says Kizer.
The other recommended mod is to lower compression ratio from the ZZ-R´s 11:1, which in this motor Kizer has done using specially designed Wiseco pistons giving 9.5:1 with a capacity increase from 1052 to 1109cc. Considering the extra power being produced, very little strengthening work is necessary. The Kawa´s cylinder head, cams, valve train and gearbox are untouched; the clutch gets a set of stiffer springs.
One important lesson Kizer has learned is that the ZZ-R´s number three conrod can suffer from lack of oil pressure under extreme duress. He has developed a kit that takes extra oil from the pump to the right side of the bottom-end. That cures the problem, he says, and means this engine´s Carillo rods are not strictly necessary. (The oil kit costs $150 plus the customer’s original sump pan, and bolts straight on.)
It´s time to go. The motor fires up readily, with a menacing burble through the four-into-one. The stiffer clutch springs are noticeable, though not excessively so. At low revs the bike feels a little woolly, idling at 2000 to 3000rpm and occasionally dying at a standstill – probably due to richness caused by the high-pressure injection system. (Kizer says he could improve it given a little time; we´ve arrived unexpectedly and caught him unprepared.)
Provided I keep the revs to about 4000rpm the Kawasaki pulls away smoothly, and it´s manageable even when we head into downtown Houston to take photos in the shadow of the skyscrapers. At lowish engine speeds, with no boost showing on the gauge, there´s the slightly remote connection between throttle and engine output – almost as though the throttle cable is made of elastic – that is typical of a turbo.
You have to keep the revs up and the boost just showing to make the engine respond crisply, so using all the performance on a twisty road would be difficult. The Kawasaki is well-balanced as the road curves a little on the way out of town, though, its stock chassis and Metzeler ME1s feeling well up to the job. And it´s for straight-line speed that this bike was built. Kizer knows where to find a wide, little-used road consisting of sections of straight tarmac connected by the occasional sweeping curve.
When we arrive he leaps out of his pick-up, pulls on a helmet and roars off to check-out the bike, returning ten minutes later with a broad smile on his face and a muttered warning that ‘you could loop this thang in third, real easy´. He´s not joking. With five grand on the tacho and the turbocharger starting to blow, snapping open the throttle would put you straight on your head to be trampled by 250 stampeding stallions. In a third gear roll-on test, this bike has accelerated from 50mph to over 125mph in 200 yards – with 20lb of ballast added to keep the front wheel somewhere near the ground.
I´m expecting serious speed, but nothing has prepared me for the way the ZZ-R takes off in fourth gear. The exhaust note is drowned-out by the hiss from beneath the tank, my right wrist involuntarily shuts off momentarily as the front wheel lifts at over 100mph, my left foot flicks into fifth and then top as the revs climb with stunning rapidity, and the Kawasaki simply keeps accelerating as though there is no limit to the speed it will reach.
At full boost in top gear there´s no time to take my eyes off the road to look at the speedo, but on standard gearing the ZZ-R comes close to hitting its 11,500rpm rev-limiter ludicrously quickly. More than just the sheer velocity, it´s the way this bike gets there that is so impressive. When a stock ZZ-R1100 would be running out of steam, the turbo-bike is still accelerating like a fighter-plane. What had seemed like a straight, empty road instantly becomes anything but.
The bike´s top-speed potential was not realised even by that 215mph run in the middle of the Californian desert, Kizer claims. There, the Kawasaki hit its limiter while fitted with a 38-tooth rear sprocket – the smallest that would fit on the standard rear wheel – in place of the stock 45-toother. ‘I´d like to go where there´s some accurate clocks, where we could put more gearing on it and concentrate on the aerodynamics,´ he says. ‘This bike could go to 230mph.´
Outrageous? Certainly. But after feeling the force of the Mr Turbo ZZ-R1100, I wouldn´t bet against it. The ZZ-R1100 turbo kit costs $4995, which includes the turbo itself, fuel-injection system and all necessary fittings. (Kizer estimates eight to 12 hours for assembly.)
Get Kawasaki motorcycle insurance for the kawasaki zzr1100 mr turbo.
Engine Watercooled 16-valve DOHC transverse four
Claimed power (bhp) 180bhp @ max boost
Compression ratio 9.5:1
Transmission 6 speed
Stock ZZR1100 chassis
228kg (502lb) dry
Top speed Quarter mile; 10.8sec@130mphmph
215mph ( est )
Current price The water-injection system costs an extra $275. Kits for other bikes cost between $2450 and $2750, using a carburettor.