750cc Sportbikes

The 750cc Sportsbike has always been synonymous with racing, with the large majority of examples being built to race.

The 750cc Sportsbike can be traced back to 1969 when Honda introduced the CB750; it was a revolution, featuring an in-line four-cylinder four-stroke engine producing a claimed 67bhp and capable of hitting a top speed of around 120mph. The motorcycle proved a huge sales success for Honda, it was far more technologically advanced than anything built before and was also very reliable. The CB750 was arguably the first of the Japanese breed of motorcycles that lead to the demise of the British motorcycle industry.

By The original uploader was ↑ＰＯＮ at Japanese Wikipedia (Transferred from ja.wikipedia to Commons.) [GFDL or CC-BY-SA-3.0], via Wikimedia Commons

The 1980’s

The first of the 750cc Sportsbikes as we know them today, the ‘race replica’, was the Suzuki GSX-R750 launched in 1985. It was designed to bring the race bike to the road. It featured full fairing as well as an alloy, rather than commonly used steel, frame taking inspiration from race bikes of the time. The first incarnation of the GSX-R750 was light and powerful (claimed 179kg, 106bhp), and fast at just over 140mph. So focused were Suzuki on creating a light weight 750cc motorcycle they opted for the engine to be both air cooled and oil cooled; arguing that a liquid cooled engine would be both larger and heavier. In the same year Yamaha launched the FZ750 and in 1986 both Honda and Kawasaki launched further new models: the VFR750F (also known as the interceptor) and the GPX750R respectively. Although the manufacturers had propositions to race in WSB the motorcycles were arguably a couple of years late: the GSX-R750 had moved the game on.

By Heineken (Own work) [CC BY-SA 3.0 or GFDL], via Wikimedia Commons

In 1987 Bimota launched the YB4E1, originally designed as a race only motorcycle, however to compete in WSB Bimota had to produce at least 200 road going examples to receive homologation. The ‘Y’ in its name referred to Yamaha; the YB4 used the engine from the Yamaha FZ750. Bimota were famed for building advanced frames and the YB4 was no different using a strong, yet lightweight, alloy perimeter frame: this was at a time when the competition was still using either steel or double cradle alloy frames. Rather embarrassingly for Yamaha the YB4, as a complete package, was in a totally different league to the FZ750 and a very serious contender for the GSX-R750.

By 1988, spurred on by Bimota’s success, Yamaha canned the FZ750 in racing (although it was still available as a road going model) and launched the FZR750R OW01. The OW01 was a homologation special built purely to race and win in WSB. It featured a totally new and more powerful engine as well as having a lightweight alloy perimeter frame. The OW01 was a serious bit of kit, however also in 1988 Honda launched one of motorcycling’s most iconic bikes: the VFR750R also known as the RC30. The Honda RC30 was a total revolution, powered by a V4 four-stroke engine that provided linear power with amazing traction. Like the OW01 the RC30 was built as a homologation special with no expense spared, with a sole purpose to win: unfortunately for Yamaha it did win taking the 1988 WSB title.

In 1989 Kawasaki introduced the ZXR750 H1 to replace the extremely aged GPX750R. The H1 was based on the 1988 Kawasaki ZXR-7 race bike. Like the OW01 and the RC30 the ZXR-7 was a no expense spared showcase of Kawasaki’s engineering ability, it was however a prototype rather than a homologation motorcycle and was built to compete in endurance racing; not WSB. Like the ZXR-7 the ZXR750 was a serious contender; it shared the same engine as GPX750R engine but was totally reworked and updated. More importantly it incorporated advances in chassis technology adopted by the competition. The ZXR750 was arguably the first of the 750cc Sportsbikes to bring this technology to the masses: it had a retail price of around half that of the OW01 and RC30. Honda continued to offer the more road orientated VFR750L as a rival, however it was much less of a race replica and as time went on the VFR750L become much renowned as a Tourer. Kawasaki’s new offering, all though good as it was, couldn’t quite compete with the dominance of the RC30 that also took the WSB title in 1989.

The 1990’s

The Kawasaki ZXR750 continued to be tweaked and in 1991 the H model was replaced with the ZXR750 J1 (known as the J2 in 1992). The new model used the engine as a stressed member and incorporated Upside Down Forks (USD forks) rather than conventional inverted forks: both increasing the rigidity of the chassis. The J1 and J2 were restricted to 100bhp by Kawasaki, the reason being that there was supposedly a 100bhp limit imposed by European law: however, the ban never came about, leaving the ZXR750 at quite a disadvantage to its rivals as a road bike. In 1996 Kawasaki launched an all new model, the ZX7R. The ZX7R featured twin ram-air intakes, hugely impressive for the time 6-pot brake callipers and fully adjustable suspension. The ZX7R was a big success on the road and track, it was fast, powerful, yet sure footed.

By Huetchen (Own work) [CC BY-SA 3.0], via Wikimedia Commons

The GSX-R750 also continued to evolve with a new model being introduced in 1988 and later updated to incorporate USD forks. However it wasn’t until 1992 that the engine finally moved from oil and air-cooled to liquid-cooled following the footsteps of the competition. In 1995 Suzuki introduced the GSX-R750 SRAD; a fantastically capable Sportsbike on the track and road. The road bike was a huge sales success taking on, and some would say bettering, the much larger capacity sports bikes of the time such as the Honda Fireblade (also known as the Blade).

Yamaha replaced their two 750cc Sportsbike offerings, the OW01 and the FZ-750, with the YZF750 in 1993. The YZF750 was arguably the first serious 750cc Sportsbike offering from Yamaha that was affordable to the everyday man. It featured USD forks, a lightweight twin spar alloy frame and engine with a claimed 125bhp output: capable of hitting 160mph. In 1999 Yamaha built a further homologation special the R7 also known as the OW02, like its older brother it was built to win, however success was limited due to the rules in WSB favouring twin cylinder motorcycles.

The RC30 was replaced in 1994 by the RVF750R RC45. The RC45 was essentially an evolution of the RC30 incorporating advances in engine, braking and chassis technology. Like the RC30, the RC45 was built as a pretty much a no expense spared homologation special to win WSB. However, it was a title that the RC45 didn’t win until 1997. By the late 90’s the RC45 had a big disadvantage against its larger capacity V-Twin rivals.

Today

The rule books for WSB were pretty much to blame for killing the 750cc Sportsbikes breed. With the rules of the 90’s allowing V-Twin motorcycles to have engines of up to 1,000cc and four cylinder motorcycles to have engines of up to 750cc, Suzuki and Honda soon switched their focus on developing the V-Twin engine: with Suzuki moving to the TL1000R and Honda moving to the RC51 (SP1 & SP2) joining the other V-Twin offerings from Ducati and Aprilia. The four cylinder motorcycles that remained: the Yamaha R7 and Kawaskai ZX7R just couldn’t compete.

Rare and beautiful R7 OW02 spotted at 2016 Bemsee (BMCRC) Round 1, Brands Hatch.