SR Archive: Muzzy Raptor 850 Streetbike Test

This ain't no 750! Hunting for prey aboard the Muzzy Raptor 850

This article was originally published in the April 1998 issue of Sport Rider.

Muzzy Raptor 850 test
Muzzy Raptor 850 is an absolute 180 mph beast for those who think they might have the right stuff.Photography by Fran Kuhn

Once in a while, a bike will come along that not only stands out from the crowd by virtue of its remarkable performance, but also due to its sheer visceral appeal. A bike that, upon start-up, not only causes the rider’s pulse to quicken, but those around him as well. A motorcycle that basically grabs you by the throat, slaps you in the face a few times, and stamps the words “ABSOLUTE HIGH-PERFORMANCE: CAN YOU HANDLE IT?” indelibly across your forehead when you twist the throttle. This machine—the Muzzy Raptor 850—is one of those bikes.

Muzzy Raptor 850
The trick titanium/carbon-fiber muffler “high-pipe” exhaust comes stock with the RAM single-sided swingarm option. Footpegs and brackets are Muzzys Supersport racing items; note the carbon-fiber plate fitted over the swingarm pivot, which is relocated for better rear tire traction.Photography by Fran Kuhn

Here is a motorcycle that threatens to loop over backward anywhere near full throttle in first gear, even with its tall gearing. It pulls through the upper gears with an irrepressible intensity that can only be likened to a supercharged locomotive running on nitromethane. And to anyone with even a hint of racing or performance in their blood, its raucous bark at full chat is music to the ears. And, it’s street legal.

When you think of Kawasakis and racing, only one name comes to mind: Rob Muzzy. The man with the trademark handlebar mustache has forged a legendary reputation for extracting winning performance from Kawasakis for almost two decades. A World Superbike championship and numerous AMA national championships highlight his long list of accomplishments. So when Muzzy speaks performance, well, people listen.

Muzzy Raptor 850 test
The svelte solo-seat fiberglass tailpiece is made in-house at Muzzys. There aren’t any plans for a passenger seat, and we doubt anyone would be foolish enough to ride on the back anyway.Photography by Fran Kuhn

In the past when we've done project racebikes with Muzzy, he's preferred not to participate in a partial manner. His response, when we inquire about Muzzys supplying a few parts, is frequently "instead of us just providing a few pieces, why don't we just take care of the whole bike for you?" That way, he knows the bike will be assembled correctly, and will perform up to his expectations.

So the same philosophy has been applied to the Muzzy Raptor 850. In the tradition of aftermarket custom cars like the Shelby Cobras and Saleen Mustangs, Muzzy has chosen to take a stock ZX-7R Kawasaki and weave his particular brand of magic over the bike; then sell it to the consumer as a complete motorcycle. The components that go into building this machine will not be available in kit form—you won't be able to build your own Raptor. "Raptor owners need to know that the guy down the street with a ZX-7R can't go out and build his own," says Muzzy's press liaison Doug Meyer. Thus, the performance won't be the only aspect of the bike that will be exclusive. (Unfortunately for California residents, the Raptors will be 49-state legal only.)

Muzzy Raptor 850 test
Rob Muzzy himself is responsible for the distinctive front fairing design. Using clay for a mock-up, he redesigned the ram-air inlet, combining the dual intakes into one and repositioning it on the leading edge of the fairing for optimum ram effect.Photography by Fran Kuhn

Muzzy has previously applied the same principle of selling complete, ready-to-roll motorcycles with his Raptor SB-850 Formula USA racebikes. Essentially a racebike that a privateer racer can purchase and immediately be competitive on, an SB-850 F-USA Raptor piloted by David Sadowski won the anything-goes Formula USA series championship last year in its first full season of competition. Racing against monster 1200cc-plus GSX-Rs and the like, the F-USA Raptor (which, incidentally, is claimed to put out 178 horsepower at the crank) proved its mettle in the face of much larger adversaries. The Raptor 850 streetbike is a very close derivative of this machine. (This isn't the "750" Raptor you've seen tested in another magazine; this is the full-bore, all-out, give-me-all-you've-got-Scotty version.)

In order to obtain one of these beasts, you’ll need to go to a Kawasaki dealer, and buy a ZX-7R. The dealer then ships the crated bike over to Muzzys along with the purchase order. Upon receipt, the bikes are disassembled down to the frame and then carefully built by Muzzys employees, whose sole purpose is to construct Raptors. The engines are put together in the race shop by Raptor-only technicians (none of this “Hey Gary, uh…can you throw a Raptor engine together when you get a spare minute?”), while two assemblers dedicated exclusively to the bikes handle the construction chores. In fact, each Raptor is assembled by one person from start to finish: “The customer is basically getting a custom-built motorcycle,” says Meyer.

Muzzy Raptor 850 test
This rip-roarin' ride has blinding acceleration with brakes and chassis to match.Photography by Fran Kuhn

Starting with the motor, the stock crankshaft is replaced by a forged billet piece sporting a 47.3mm stroke (not a welded stroker crank), 2.6mm more than stock. Together with the 75mm (2mm overbore), 3-ring, forged-alloy pistons forcing a compression ratio of 13.2:1, total displacement is bumped up to 835cc. The cylinder head is blueprinted (no major port work), with the carb manifolds coming out of a Kawasaki superbike race kit; cams are a Muzzys-specified grind. Everything else in the head is stock. The 41mm Keihin flat-slide carbs (which are racing carbs retrofitted with street-based fuel metering, not just slapped-on ZX-7R carbs) breathe through a carbon-fiber, ram-airbox modeled after the race kit piece; modified to accept an air filter. All this exhales through a beautiful titanium/ carbon muffler exhaust, with a unique high-pipe design on our test unit intended to work with the optional RAM single-sided swingarm.

Muzzy Raptor 850 test
The adjustable rear ride height on our test bike was jacked up pretty high, which aided steering, but caused some minor handling problems. Rear rim is a 6.0 x 17- inch Marchesini, capped with Dunlop D207 GP rubber.Photography by Fran Kuhn

Muzzy himself is responsible for the Raptor’s distinctive fairing design, using a clay mock-up to reposition the ram-air inlet at the fairing’s leading edge. All the fiberglass/composite bodywork, including the solo tailpiece/seat assembly, is made in-house at Muzzys. Construction is high quality throughout, with none of the rough edges or poor layering we’ve seen with some other aftermarket pieces. A liquid-looking black paint job finishes the aesthetics, although a Kawasaki racing green option ($325) is available. We prefer the stealthiness of black, but considering this bike’s in-your-face persona….

The most unique chassis alteration is obviously the trick RAM cast-magnesium, single-sided swingarm, which is a $3749 option. Chain adjustment with this swingarm is by eccentric pivot, which requires a special tool that Muzzys provides. The swing­arm’s nominal length is stock; so swiveling the eccentric adjuster can shorten the wheelbase by as much as 1.3 inches (however, the eccentric can also affect rear ride height). Wheel control is handled by a Type-4 Öhlins piggyback racing shock, which features the remote hydraulic spring preload adjuster. The shock works through a Muzzys-designed linkage which provides a racing-derived, less-progressive mechanical rate, aiding chassis control through the bumps. The swing­arm pivot has also been relocated for improved traction.

Muzzy Raptor 850 test
The well-made carbon-fiber ram airbox is closely based on the Kawasaki superbike race kit component, but modified to work with an air filter.Photography by Fran Kuhn

Up front, the stock KYB cartridge forks are reworked with a different valving shim stack, cartridge piston, and springs; all developed from Muzzys’ racing programs. Gripping the forks are a pair of beautifully machined, black-anodized, billet aluminum triple clamps which feature wider spacing (228mm) of the fork tubes; this was found to markedly improve the handling on Chandler’s superbike. The offset is adjustable as well, using different eccentric steering head inserts. For those feeling exceedingly rich, a set of Öhlins racing forks are available as a $7500 option, but an Öhlins steering damper does come standard on the Raptor 850.

Rolling stock consists of Marchesini magnesium wheels measuring 3.5 x 17 inches in front, 6.0 x 17 inches out back, shod with the ubiquitous stick-like-flypaper Dunlop D207 GP radials. Braking duties are entrusted to a pair of stock Tokico six-piston calipers gripping 320mm Braking Carbiron rotors, while either an AP or Brembo two-pot jobbie (vendor hadn’t been decided at presstime) bites on a 270mm stainless steel disc in the rear.

Muzzy Raptor 850 test
Popping the lid reveals a bank of 41mm Keihin flat-slide racing carbs, reworked with street-based fuel circuits, as well as a choke. Carburetion was well-dialed, with only a slight stumble when you grabbed a handful at 5000 rpm.Photography by Fran Kuhn

Riding the Raptor 850 on the street showcased its ability to remain civil (uh, to a certain extent). Unlike many racing flat-slide carbureted bikes we’ve tried, the Raptor runs smoothly. If you whack the throttle open below 5000 rpm it does stumble, but it cleans out quickly. That’s where the civility ends, however, as you’ll soon find yourself pointing at various cloud formations with the front wheel.

Testing at the high-speed expanse of Willow Spring’s big, nine-turn road course proved eye-opening, to say the least. “You’ll probably need the big track to let the Raptor 850 stretch its legs a bit,” said Meyer; he wasn’t kidding. With a dyno-confirmed 147.2 horsepower at the rear wheel, the Raptor 850 basically gobbled up Willow’s long straights with alarming quickness. The pull off the corners generated by this bike must be felt to be believed. Fortunately, the brakes were up to the task of scrubbing off that speed. The Braking Carbiron rotor/pad setup offered excellent stopping power, albeit with a slightly softer initial response than the stock binders. Some riders prefer the softer response, saying that it gives them more modulation during hard braking.

Muzzy Raptor 850 test
The black-anodized, billet aluminum triple clamps feature wider fork tube spacing than stock, a handling improvement trick learned from Chandler’s superbike; note the engraved Raptor insignia. Low-cut windscreen reduces aerodynamic frontal area.Photography by Fran Kuhn

Riding the tighter Streets of Willow course, which more closely resembles real-world riding conditions, became an exercise in throttle control. The Raptor’s quick-revving motor and beefy power spread meant that an over-eager throttle hand would either have you spinning the tire or understeering off the corner, due to the front tire pawing for the sky. Steering was much quicker and lighter than a stock 7R, attributable to a substantial weight loss (425 pounds dry, versus the stocker’s 490 pounds), and the steeper rake angle (24 versus 25 degrees), imposed by the radically jacked-up rear ride height. The steep rake allowed the use of tighter lines unattainable by the stocker, but it also enforced smooth throttle control. Chopping the throttle entering high-speed turn eight on the big Willow course caused the Raptor to “wind up” into an oscillating weave. Time constraints unfortunately prevented us from experimenting with different chassis ride heights, which we’re sure would’ve cured the problem.

Muzzy Raptor 850 test
Of course, what Raptor ownership would be complete without a nicely detailed Muzzys carbon-fiber key fob?Photography by Fran Kuhn

Those same time constraints hampered the top speed and dragstrip portion of our testing, as well. Although the Raptor 850 quickly posted a very impressive 179.2-mph blast, we’re certain that a bit more time experimenting with jetting and gearing would’ve easily netted a 180-plus mph mark. It should be noted that the Raptor’s superb torque enabled it to reach that speed with surprising quickness, much faster than production bikes that are anywhere close to that territory.

Muzzy Raptor 850 test
The Raptor 850 is a bike that possesses killer performance and transcends all other machinery.Photography by Fran Kuhn

Heavy rains inundated LACR’s quarter-mile track with dirt prior to our visit, forcing a clean-up that lasted well into the time allotted for the Raptor 850’s dragstrip testing. A bare handful of runs with minimal time for setup netted a somewhat disappointing best of 10.28 @ 142.21 mph. Good launches were hindered by a rather vague clutch feel, which forced us to battle with the Raptor’s wheelie tendencies due to its massive torque. With just a bit more time to get accustomed to the clutch, we’re certain that a nine-second run would have been in the cards. Roll-on tests were canceled, which, even with the flat-slide carb’s slight finickiness, would surely have been impressive—judging by the Raptor’s torque curve.

Muzzy Raptor 850 test
Front brakes consist of stock Tokico six-piston calipers, with Braking Carbiron 320mm rotors; performance is excellent. Front wheel is a 3.5-inch-wide Marchesini, rolling on a gumball Dunlop D207F GP radial.Photography by Fran Kuhn

In this age of ever-increasing performance from showroom-stock sportbikes, there’s something to be said for a bike that combines standard-setting speed, exclusivity and trickness with a raw, visceral appeal that can’t be matched. For many, the Muzzy Raptor 850’s price tag ($25,727 as tested, with the single-sided swingarm option) may seem lofty. But for those interested in a bike that not only possesses killer performance, but communicates that message to the rider in a way that transcends all other machinery, it’s worth it.

Muzzy Raptor 850 test
Beautiful carbon-fiber pieces are everywhere on the Muzzy Raptor 850, including these ram-air inlets leading into the airbox; an Öhlins steering damper is mounted horizontally across the steering head.Photography by Fran Kuhn
Muzzy Raptor 850 test
The beautiful RAM cast-magnesium single-sided swingarm (a $3749 option) comes with a special tool for the eccentric axle/chain adjuster. The Öhlins Type-4 rear shock features a remote hydraulic preload adjuster.Photography by Fran Kuhn
Muzzy Raptor Temp Gauge
High Low
The rip-snortinest, rompin'-stompinest sportbike you can buy from a dealer Lofty price tag
Trick parts galore Exhaust bark at anywhere near full throttle can attract unwanted attention
Blinding acceleration, with brakes and chassis to match Not civilized, but who cares?
Muzzy Raptor 850 test
The Muzzy Raptor 850 comes with a 3000 mile/90-day warranty. Any problems encountered by a customer are dealt with personally by Raptor-specific employees at Muzzys.Photography by Fran Kuhn

Muzzy Raptor 850
Price: $25,727 (as tested, with single-sided swingarm option)

Type: Liquid-cooled, four-cylinder, transverse, in-line 4-stroke
Valve arrangement: DOHC, 4 valves/cyl.
Displacement: 835cc
Bore x Stroke: 75.0 x 47.3mm
Compression ratio: 13.2:1
Carburetion: 4, 41mm Keihin flat-slide racing
Transmission: 6-speed, wet clutch

Front suspension: 43mm Muzzys-revalved KYB inverted cartridge, 4.7 in. travel; adjustments for ride height, rebound and compression damping
Rear suspension: Single Öhlins Type-4 shock, 5.1 in. travel; adjustments for ride height, spring preload, rebound and compression damping.
Front brake: 2, Tokico six-piston calipers, 320mm Braking Carbiron discs
Rear brake: Two-piston caliper, 270mm disc
Front wheel: Marchesini 3.5 x 17 in.; cast magnesium
Rear wheel: Marchesini 6.0 x 17 in.; cast magnesium
Front tire: 120/70ZR17 Dunlop D207F GP radial
Rear tire: 180/55ZR17 Dunlop D207 GP radial
Rake/trail: 24 deg./4.0 in. (101mm; adjustable)
Wheelbase: 55.2 in. (1402mm, adjustable +1.3 in. [33.02mm])
Seat height: 32.0 in. (812.8mm, variable)
Fuel capacity: 4.8 gal (18.1L)
Weight: 454 lbs (205.8kg) wet, 425 lbs (192.7kg) dry

Instruments: Speedometer, tachometer, odometer, tripmeter, coolant temperature gauge; lights for neutral, high beam, turn signals, low oil pressure

Fuel consumption: N/A
Top speed: 179.2 mph
1/4 mile: 10.28 @ 142.21 mph
Roll ons: N/A


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