Misplaced Pages

#56943

30-454: The 67 bhp (50 kW) R90S had a top speed of 124 mph (200 km/h), it ran the quarter mile in around 13.5 seconds and it accelerated from 0 to 62 mph (0–100 km/h) in 4.8 seconds. Maximum torque was delivered at 5,500 rpm and the engine redlined at 7,200 rpm. The R90S' type 247 "airhead" engine was a pushrod OHV , two valve per cylinder , air-cooled flat-twin "boxer" unit. The engine

60-427: A 9.5:1 compression ratio, while the less sporty R90/6 had a ratio of 9:1. The alloy wheels were spoked and wore tubed tyres. The front brake had twin 230 mm disks and ATE callipers; the rear brake was a 200 mm SLS drum. The R90S and the other BMW "/6" series front brakes had an unusual system whereby a master cylinder on the top frame tube was activated by a cable from the front brake lever. This arrangement

90-475: A bike which is built in just enough numbers to satisfy the production rule. (Typically 5,000 units sold worldwide). That bike, the Honda Interceptor VF750F was a huge departure from the air-cooled, four valve per cylinder CB-750F launched in 1979. It featured a square tube steel perimeter frame which wrapped around the outside of the engine, rather than the older hidden round-tube frames. It

120-436: A redesigned seat, with a small "ducktail" fairing which (in addition to an underseat tool tray) provided a small storage space for lightweight items such as waterproofs. Standard equipment included a full toolkit, a hand pump, a first-aid kit and even a small hand towel with an embroidered BMW logo. The R90S had a small bikini fairing which housed two analogue instruments: a clock and a voltmeter. Its 238 watt alternator

150-485: Is an air-cooled flat-twin motorcycle engine with two valves per cylinder, also known as " airhead " boxer. The 247 engine was the successor of the in 1969 (MY 1970) introduced first modern BMW boxer engine; the BMW 246 engine of the /5 series. With minor and more significant updates (247/76 in 1976 and 247/M80 in 1981) it was used by BMW beginning with the 1974 /6 series in its motorcycles from 1974 to 1995. Before 1981

180-537: The 1000cc four cylinder bikes producing up to 150 horsepower were able to achieve were overwhelming the stock frames, suspension and tires of the era. Thus for 1983 the AMA, working with the top teams, decided to reduce the maximum capacity of the Superbike class to 750cc. Honda, which had been competing in the series on their CB 750F was ready with a new bike in 1983, initially planned as a "homologation special" that is,

210-731: The FIM MotoGP and World Superbike Championships). KRAVE organized multiple championship road racing series for the AMA, which are collectively known as the MotoAmerica Road Racing Series beginning in 2015. MotoAmerica chose to align the multiple racing classes closely with those used by FIM, which simplifies the work that manufacturers must do to compete in both series. The most successful riders included Doug Chandler , Scott Russell , Ben Spies , Miguel Duhamel and Mat Mladin , who holds several series records including seven championships. Five non-Americans won

240-607: The Japanese bikes produced more horsepower, the European bikes tended to have superior handling. The inaugural series in 1976 was won by rider Reg Pridmore on a BMW R90S owned by Team Butler and Smith. European machines won every race in 1976 and the first half of the 1977 series, but after two seasons of work the Team Racecrafters Kawasaki KZ 1000, again piloted by Reg Pridmore, won the first race for

270-473: The Japanese. With the advent later that year of the better handling Suzuki GS 1000, the less powerful twin-cylinder European bike's race domination was over. As the series gained more and more attention in America the factories took note, and in 1980 Honda entered the series with a factory team and brought a top rider from their stable, Freddie Spencer, to compete on their behalf. Up until this point Honda and

300-683: The R100CS had black-painted "squared" valve covers. The other bikes in the BMW "/6" range were the new R90/6, the R75/6, and the R60/6. The 500cc R50/5 was discontinued and no "R50/6" version was produced. A later example of the R259 oilhead BMW, the R850/1100R, sported a similar two-tone smoke grey paint scheme in homage to the original BMW 'superbike' color scheme. Two R90S bikes placed first and second at

330-569: The R32 of 1923. After the type 247, BMW substantially changed the engine design to include partial oil cooling and four valves per cylinder, a design which was to become known as the " oilhead ". This motorcycle, scooter or moped-related article is a stub . You can help Misplaced Pages by expanding it . AMA Superbike Championship AMA Superbike Championship is an American motorcycle racing series that has been run every year beginning in 1976. For most of its existence it has been considered

SECTION 10

#1732791361057

360-599: The United States was the AMA Grand National Series which required competition in five different formats 1/4 mile, 1/2 mile, 1 mile and TT courses, which were all run on dirt ovals, and pavement racing. Europe, under the guidance of the FIM, or Fédération Internationale de Motocyclisme , had a much more developed motorcycle road racing world championship, but it didn't include any American venues in

390-477: The few venues where FIM style Formula 1 500cc machines raced in the United States, but by 1988 the speeds the machines were reaching on the high-banked tracks were simply too high for safety given the tire technology of the time. In 1985 the race format moved from GP bikes to Superbikes, and it became part of the AMA Superbikes series. This increased the visibility of Superbikes even further, and cemented in

420-462: The first series 14mm axle. The original R90S had "/5" switchgear, but this was changed in 1975 to a new non-standard design that proved unpopular. The engine crankcase breather was a phenolic disc-&-spring item which made a 'popping' sound as the breather operated. The modified "/7" breather was a reed valve design, which could be retro-fitted to "/6" models to replace their noisy breathers. From 1973 to 1976, 17,455 R90S models were sold. The R90S

450-697: The ignition was points ignition . From 1981, introduced in the R80G/S it used electronic ignition , Nikasil cylinders, and a lighter flywheel . A number of different models were on the market: Subsequent to the type 247 motor, BMW also built other air-cooled flat twin engines known as the Typ 248/1 used for the R45, the R65 and the R65LS BMW motorcycles. Before that they built side-valve and OHV engines commencing with

480-463: The inaugural 750cc Superbike championship, but Honda went on to win the next five years in a row of series championships with the Interceptor. As the popularity of the series grew the long established Daytona 200 motorcycle race, which had begun on a course constructed on the beach in 1935, and had moved to the asphalt auto-racing track in 1961, switched to Superbikes. The race had been one of

510-553: The minds of many Americans that the Superbikes were now the de facto premier motorcycle racers, eclipsing the FIM 500cc series, with their unavailable two-stroke racing machines. In late 2002 AMA Pro Racing, the promoter in charge of the AMA Superbike Championship at the time decided to open up the series to 1000cc production bikes. Their plan called for allowing near-stock 1000cc machines to compete against

540-517: The other Japanese manufacturers were more focused on the International Grand Prix and in particular its premier 500cc Series, which was run on purpose built 500cc racing motorcycles. By 1980 the 500cc class was completely dominated by two-stroke machines, which at the same time had been phased out for road use in many countries. The American Superbike Series was suddenly more relevant and appealing to manufacturers. The speeds that

570-554: The premier motorcycle road racing series in the United States. It is sanctioned by the AMA American Motorcyclist Association since its inception, and the promotion of the series has been licensed to several organizations over the years. Since 2015 the series has been run and promoted by MotoAmerica , who also manage several other AMA professional road racing championships, including the popular 600cc Supersport class. The AMA Superbike Championship

600-510: The series popular with fans, racers and after several seasons motorcycle manufacturers took a direct interest and began sponsoring teams and riders. At the inception of the series there was stiff competition between the more experienced teams racing European twin cylinder bikes, which included the BMW R90S, Ducati and MotoGuzzi motorcycles and the teams racing the more powerful Japanese inline fours from Kawasaki, Suzuki, Honda and Yamaha. While

630-495: The series. In 1986, the AMA recognized the changing nature of motorcycle racing by making the Grand National Championship into a dirt-track-only series; road-racing rounds were branched off into a separate championship which was named the AMA Superbike Championship. The fact that the rules were set up to compete using the same large displacement production bikes that people saw in the showrooms quickly made

SECTION 20

#1732791361057

660-474: The then-current state of the art 750cc Superbikes that were the incumbent series competition machines. In addition, they would be allowed to increase their capacity to 800cc. The complicated rules allowed "claiming" of the 1000cc stock machines, a technique where competitors can buy the winning machine from the owner for a set amount of money, and intended to keep modifications down in near-stock racing classes. Ultimately this complicated mix of machines and rules

690-517: The very first AMA Superbike race at Daytona International Speedway in 1976. On the first place bike was Steve McLaughlin and on the second was Reg Pridmore . The first place bike is now in the BMW Mobil Tradition Collection. British rider Reg Pridmore rode an R90S to win the 1977 AMA Superbike Championship . [REDACTED] Media related to BMW R90 at Wikimedia Commons BMW 247 engine The BMW 247 engine

720-415: Was a water cooled V4 with four valves per-cylinder. Originally Honda had planned only to make enough to meet the requirement for production racing, but the bike was extremely popular, even at the price which was higher than the older CB-750, and it went into full production. Honda was unsuccessful in winning the championship with the new bike in 1983, as Wayne Rainey riding on Team Muzzy Kawasaki GPz 750 won

750-565: Was based closely on the R75/5 , sharing the same stroke, but with a larger bore, to give a capacity of 898cc. The R90S weighed 215 kg (474 lb) and has a five-speed gearbox with a shaft final drive . The first R90S models had a two-tone paintwork scheme of "Smoke Black/Silver" with adhesive gold pinstripes. Feedback from unimpressed customers prompted BMW to return to hand painted pinstripes. Later R90S models were available also in two-tone "Daytona Orange" with red pinstriping. The R90S had

780-482: Was created in 1976 as a new motorcycle road racing series taking advantage of the newest large displacement production road-going motorcycles of up to 1000cc's that were increasingly popular with American riders. The series was initially called "Superbike Production" and was initially modeled on a regional series that had been run in California in the previous years. Up until this the most prestigious racing series in

810-503: Was later upgraded to 250 watt. An adjustable hydraulic steering damper was manually adjusted via a knob on the steering head. Suspension was by long-travel telescopic forks and twin rear shocks whose rear dampers were adjustable for preload (the only suspension adjustment available). Whereas other BMW boxers had Bing slide constant velocity carburetor , the R90S was fitted with accelerator pump Dell'Orto carburetors. The R90S engine had

840-606: Was not liked by many of the competitors. In 2006 Ducati withdrew factory support from AMA Superbike racing, and in 2008 Honda followed suit. From 2009 to 2014, the Daytona Motorsports Group was the organizer under supervision of the AMA. The AMA, not pleased with motorcycle counts and participation in their events, stripped the DMG organization of the sanction and awarded it to a new organization led by Wayne Rainey , KRAVE, with assistance from Dorna (which organises

870-507: Was succeeded in 1977 by the R100S, which retained the bikini fairing with altered paintwork, and whose engine capacity was increased to 1,000 cc. The R100S reverted to using 40 mm Bing CV carbs. The BMW flagship mantle passed to the R100RS, which now sported a full fairing. Other factory variants included the R100CS of 1983–1984. The R90S always had "/5" type "round" valve covers, but

900-470: Was supposed to protect the master cylinder in the event of a crash; but later "/7" machines adopted a conventional handlebar -mounted Brembo master cylinder. There were three series of the R90S: Other differences distinguish the three series: After the first series, brake discs were drilled. The first series kept the "/5" series kick start lever. The later 17mm diameter front axle was stronger than

#56943