Origins of the Honda VFR750F
So poor was the V4 engine’s image in the mid-eighties that Honda was on the verge of abandoning it. The firm’s reputation for solid reliability was in tatters following a bungled response to problems that had emerged with its VF750F sports bike that was part of a complete range of sophisticated liquid-cooled 16-valve V4s. Camshaft bearings and lobes had been wearing prematurely but Honda failed to solve quickly what was basically a simple production issue. Yet the V4 range offered impressive performance (at a price) and reflected Honda’s dominance in road racing: Joey Dunlop had been the owner of the Formula 1 title for three years, but this wasn’t enough to compensate for the contempt that the public had for the V4 engine. The UK and Germany were lone voices fighting for the V4’s reputation. Honda UK’S Roger Etcell was sales manager at the time: “In 1985 we had an all-day R&D meeting in Germany and the V4 debate took us late into the night when only myself for the UK and a colleague from Honda Germany wanted the V4 to continue! The R&D people were ready to give up and focus on a new range of inline fours: the CBR600 and CBR1000F, while other countries (including North America) were happy to see the back of the V4! My point was that the V4 concept was right and that R&D knew what was wrong and the best way to redress the negative PR was to produce something 110% better. In the end R&D went away to design something special alongside the new inline models.” The result was revealed at a press conference during the Bol d’or 24-hour race in September 1985 when an all-new 750cc V4 was unveiled, the VFR750F. The bike was completely redesigned in every way except for its V4 layout. Most obvious change was the use of a light alloy beam frame and a much more compact appearance. But firing up the engine revealed more significant changes had been made by Honda’s engineers: it sounded more melodic with a mechanical ring to the engine. Power was up and weight down. And true to its long-term strategy, Honda was offering a good allrounder, a sports bike that reflected its strengths in endurance racing. None of the reliability problems were officially mentioned at the press launch of the VFR750F at Jerez in southern Spain in the following February of 1986. But it was an important machine for Honda, as explained by Isamu Goto, who was managing director of Honda R&D: “We do not think that the racer replica is the proper approach to the super sports motorcycle. The aim is not simply to go as fast as possible, as it is with a racing machine; as important are elements such as the comfort of the riding position, ease of use, and the facility with which the rider comes to feel at home.” The most important feature of the engine’s design was that it used gear-driven camshafts – providing that novel sound – as introduced on the VF1000R two years earlier. Honda claimed that with the use of gears, by using two sets of idlers in
each cylinder bank taking drive direct from the centre of the crankshaft, friction losses were cut by almost a third. Power was raised to a claimed 104bhp at 10,500rpm (up by around 15bhp) by improved exhaust scavenging and a less-restricted intake system. Exhaust scavenging, and the engine’s sound, was improved by changing the crankshaft from 360º to a new layout with opposed crank pins (180º) providing even firing intervals and smoother exhaust flow. The VFR750F’S beam-style frame weighed much less than the VF750F’S, yet was 50% stiffer. Dry weight of the machine was 199kg. The original VFR750F was an important turning point in Honda’s fortunes. It was an acknowledgement that even Honda could make mistakes, and deal with them.