Yamaha YZF-750 R7 OWO2

Yamaha YZF-750 R7 OWO2
Manufacturer	Yamaha
Production	1998
Class	Motorcross
Engine	Four stroke, transverse four cylinder, DOHC, 5 valves per cylinder.
Compression ratio	11.4:1
Top Speed	174 mph / 278 km/h
Ignition	CDI
Transmission	6 Speed
Suspension	Front: 43mm Öhlins Inverted telescopic forks, preload, compression and rebound damping adjustable. Rear: Öhlins piggy-back, preload, compression and rebound damping adjustable.
Brakes	Front: 2x 320mm discs 4 piston calipers Rear: Single 245mm disc 2 piston caliper
Front Tire	120/70 ZR17
Rear Tire	180/55 ZR17
Wheelbase	1400 mm / 55.1 in
Seat Height	840 mm / 33.1 in
Weight	176 kg / 388 lbs (dry),
Recommended Oil	Yamalube 10w-40
Fuel Capacity	23 Liters / 5.8 gal
Manuals	Service Manual

It could reach a top speed of 174 mph / 278 km/h.

Engine

The engine was a Liquid cooled cooled Four stroke, transverse four cylinder, DOHC, 5 valves per cylinder.. The engine featured a 11.4:1 compression ratio.

Chassis

It came with a 120/70 ZR17 front tire and a 180/55 ZR17 rear tire. Stopping was achieved via 2x 320mm discs 4 piston calipers in the front and a Single 245mm disc 2 piston caliper in the rear. The front suspension was a 43mm Öhlins Inverted telescopic forks, preload, compression and rebound damping adjustable. while the rear was equipped with a Öhlins piggy-back, preload, compression and rebound damping adjustable.. The YZF-750 R7 OWO2 was fitted with a 23 Liters / 5.8 gal fuel tank. The bike weighed just 176 kg / 388 lbs. The wheelbase was 1400 mm / 55.1 in long.

Photos

Overview

Yamaha YZF-750 R7 OWO2

Yamaha did not pull any punches in developing the YZF-R7, codenamed the OW02. The 749cc four was created as the basis for a challenger in the World Superbike championship, and was the most sophisticated and purposeful production motorcycle that Yamaha had ever built. With only 500 units being produced, it was also one of the rarest. And at almost three times the price of the firm's open-class flagship the YZF-R1, it was one of the most expensive. More than any streetbike before it, the R7 was not simply a roadgoing machine that could be raced, but a competition motorcycle with lights and a starter-motor. The Yamaha's roots were clear from the layout of its engine, which shared the Rl 's five-valves-per-cylinder arrangement, one-piece cylinder-and-crankcase design, and vertically stacked gearbox.

Fuel-injected powerplant

Engine dimensions were identical to those of the YZF750SP, Yamaha's previous Superbike challenger. Unlike that bike the R7 was fuel-injected. Cylinder head parts were CNC (computer numeric control) machined, in Formula One racecar style, to ensure precise dimensions and perfect balance between cylinders. The lightweight internals included titanium valves and conrods, plus forged pistons with nickel-plated tops for high-revving durability. The chassis was equally exotic. The frame's black finish hinted that its design owed more to Yamaha's 500cc GP racers than to previous streetbike.

Those main frame spars incorporated an additional layer of aluminum, which helped give torsional stiffness twice that of the R1. Front forks were sophisticated 43mm upside-down units from Öhlins, who also supplied the rear shock. Steering geometry and swingarm pivot location were adjustable. The R7 was designed to be fitted with a race-kit, although this was small because the bike required a minimum of modification to be competitive on the track. (Peak output without the kit was just lOObhp, to simplify worldwide homologation.) The most important component was the large carbon-fibre airbox, which transformed the intake set-up to provide a ram-air system. Other kit parts included a competition carbon-fibre exhaust muffler.

Low clip-on handlebars, rearset footrests and a single seat confirmed the R7's racy intent. The engine's reasonable flexibility made the bike easy to ride at modest speeds, but it was at high revs that those lightweight internals came into their own, sending the Yamaha howling forward with breathtaking force. In race-kitted form, the R7 produced roughly 160bhp at 13,700rpm; enough for a top speed of 180mph (290km/h). The R7's rigid, ultra-adjustable chassis combined razor-sharp steering with amazing stability and precision. Every detail about road or track surface and traction was transmitted straight to the rider, allowing cornering control far in excess of a normal sports bike. Much credit went to the sublime Öhlins suspension. Large twin front disc brakes gave fierce stopping power, too.

Riding the R7 was a uniquely thrilling experience, but this bike was not built for ordinary roads or riders. Like its predecessor the OW01, a similarly exotic 750cc four of ten years earlier, the YZF-R7 was designed to bring World Superbike glory. The OW01 had won races but never the title. For the YZF-R7, only the delivery of Yamaha's first World Superbike championship would suffice. The YZF-R7 was designed for just one thing, and ultimately it failed to achieve it. After a disappointing learning year with the new bike in 1999, factory star Noriyuki Haga came close to lifting the World Superbike crown in 2000. But by the end of a season that was marred by a positive drug test following his use of a slimming aid during pre-season training, the Japanese ace finished second in the title race behind Honda's Colin Edwards. Yamaha then disbanded its World Superbike team. The R7's challenge was over.

Yamaha R7 Review Seven Heaven. At the end of 2000 Yamaha pulled their sublime pairing of Noriyuki Haga and the R7 superbike out of the World Superbike Championship. Haga stepped up to the 500 GPs and the R7 was left to handle domestic series like the Japanese and British Superbike championships. Ever since I first saw the Yamaha R7 I knew I would do almost anything to get a ride on it. As I am not a professional racer I’m never going to get offered a contract to ride one in the British Superbike championship so I was forced to get on the phone to Devil Contracts Inc. to ask if my soul was worth enough for a ride on an R7. Some while later, with the help of the Beelzebub himself, Yamaha UK’s press officer, I became one of the first mere mortals ever to ride the R7 superbike both on the road and on the track. The Yamaha R7 OW-O2 has just one purpose in life, to win races. It might be in the Yamaha catalogue with lights and road gear but these have only been added to gain homologate the bike within F.I.M. regulations. Only 500 are being made making it one of the rarest production bikes ever to leave a Japanese factory, and nearly every one of them will end up being raced. The R7 is fuel injected but without any ram air ducting. The engine bristles with racer-tech, including ultra-strong, ultra-light short-skirt forged pistons, with plated crowns, 24 titanium valves, an ion-nitrified crankshaft and ‘H’ section titanium con-rods. The wet multi-plate clutch features a back torque limiter to prevent to prevent lock up during aggressive down-changes. The tri-axis gearbox is a six-speed close-ratio racing set up. Yamaha claim to have based the R7 chassis as closely as possible to the two-stroke GP bike’s own chassis.

On the road I had a brief ride on the 105bhp road legal version before the track test. To say my appetite was whetted would be an understatement. The bike was faster than a ‘restricted’ bike should be and pulled hard in any gear at any speed, like a tourer. The handling was sublime, though a little hard for the bumpy country road we were riding on. Even without a damper and on brand-new road tires the bike felt very stable. I came away from my few miles aboard the standard bike thinking one thing: Get me on the race version, now! On the Track If I thought the standard road version was good, what would I make of Virgin Yamahas British Superbike version? In the paddock, as the mechanic warmed up the multi-thousand pound machine, my knees must have been visibly knocking. Was I capable of doing this bike justice? As the mechanic peeled off the tire warmers I realised I was about to find out. Out on the track I had to take it easy for a few laps, partly to get some more heat into the tires but mainly because I was feeling light headed at my good fortune. Was I really riding this fantastic motorcycle or was I dreaming? The bike was just so easy to get around the corners. My skills, or more likely my courage, ran out long before the R7 was out of tricks.

Whatever lean angle I achieved it seemed to laugh at me and dare me to lean five more degrees. No matter how hard I used the incredible race-specification brakes the bike stayed absolutely stable and just stopped. Into or out of corners the bike was ready with just as much traction as I wanted. Even trailing the brakes clumsily into a tightening right hander after missing my braking point didn’t threaten any drama. The bike just shed speed and stayed firmly on line. The engine on the R7 is an absolute gem. Just the intake sound it makes at lower revs made it worth signing that contract with Old Nick. Then, when the revs build - and they build fast, it starts screaming at you - I think it was saying “I’m faster than you, I’m faster than you...” The motor happily picked up from as low as 3,000rpm and screamed it’s way onto the rev-limiter at 14,800 like a demented rocket. The surge of power is relentless with just a small step at around 8,000rpm, no doubt there to warn you that things are about to go mental. The only thing more impressive than its speed was its tractability. Mr Miwa San, designer of this engine, you are a genius and Mr Honda wants a word with you. The Devil, on the other hand, wants a word with me. Gulp! Source

Make Model	Yamaha YZF-750 R7 OWO2
Year	1998
Engine Type	Four stroke, transverse four cylinder, DOHC, 5 valves per cylinder.
Displacement	749 cc / 45.7 cu-in
Bore X Stroke	72 x 46 mm
Compression	11.4:1
Cooling System	Liquid cooled
Exhaust	Alloy muffler
Induction	Electronic fuel injection
Ignition	CDI
Starting	Electric
Max Power	106 hp / 77.3 kW @ 11000 rpm
Max Torque	72 Nm / 7.4 kgf-m @ 9000 rpm
Transmission	6 Speed
Final Drive	Chain
Front Suspension	43mm Öhlins Inverted telescopic forks, preload, compression and rebound damping adjustable.
Front Wheel Travel	120 mm / 4.7 in
Rear Suspension	Öhlins piggy-back, preload, compression and rebound damping adjustable.
Rear Wheel Travel	138 mm / 5.4 in
Front Brakes	2x 320mm discs 4 piston calipers
Rear Brakes	Single 245mm disc 2 piston caliper
Front Tire	120/70 ZR17
Rear Tire	180/55 ZR17
Dimensions	Length 2060 mm / 81.1 in Width 720 mm / 28.3 in
Wheelbase	1400 mm / 55.1 in
Seat Height	840 mm / 33.1 in
Dry Weight	176 kg / 388 lbs
Fuel Capacity	23 Liters / 5.8 gal
Standing ¼ Mile	10.9 sec / 139 mph
Top Speed	174 mph / 278 km/h

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External Links

• http://roadcarver.com/reviews/yamaha_r7.htm