During his 20 seasons in the 500cc and MotoGP classes Valentino Rossi has won seven world titles and a record 89 races, and all but the last nine victories with long-time crew chief Jeremy Burgess. He spent four years with Honda, taking 13 victories in two seasons with the two-stoke NSR500 and another 20 in the next two seasons with the four-stroke RC211V, plus three titles. He has enjoyed the most success in his 14 years by far with the YZR-M1: 56 race wins and four world titles. 

The NSR, RC211V and YZR-M1 perfectly track the development curve of Grand Prix motorcycles over the past two decades, as engineers increased their knowledge of power delivery, chassis behaviour and electronic rider aides. 

HONDA NSR500 

2000-2001

Valentino Rossi last raced an NSR500 in November 2001, but he still rates the 500cc V4 as the best motorcycle he’s ever ridden.

“The simple truth is that no bike in the world can match a two-stroke 500,” he says. “I loved its violent character – the front tyre never on the ground and the rear tyre all over the place. Either you rode her or she punished you. There was no middle ground.”

Like all 500cc GP riders, Rossi learned to ride a 500 the hard way. He crashed out of his first two 500 GPs – at Welkom and Sepang – then finished a lowly 11th in his third, at Suzuka, 29 seconds behind winner Norick Abe.

Even crew chief Jeremy Burgess was worried by his rider’s progress. 

“Valentino was very, very badly spooked by the two non-finishes and he was very spooked by the 11th place in Japan,” recalls the Aussie, who had previously won five consecutive 500cc titles with Mick Doohan. “Suzuka was a complete shutdown of a guy who could’ve done better.”

Of course, Rossi came good on the NSR500. And he wasn’t only fast, he was clever. At the 2000 French GP he enjoyed a duel with his childhood hero Abe, during which he noticed that Abe’s Yamaha YZR500 had better drive than his NSR, which would spin the rear tyre too easily. He returned to the pits with a detailed verbal download that mightily impressed Burgess. This feedback was fed into HRC’s final 500, the NV4B.

“The NSR of 2000 had a lack of rear traction compared to the Yamaha and Suzuki, so Valentino was always spinning the rear rather than going forward,” recalls Burgess. 

“So Honda built a new bike for the last few races of 2000 and the 2001 season, with the engine higher and further back for better acceleration traction. The higher engine position also threw more weight onto the front during braking, improving traction into turns. Then we just played around with suspension and linkages to fix the speed of weight transfer from rear to front.”

HRC also created new cylinders, ignition mapping and some very special carburettors for 2001. One of the NSR’s greatest strengths was always its super-smooth and linear power curve, so when Rossi opened the throttle by 10 percent he got 10 percent more power, not eight percent or 12 percent, which was the case with most 500s. This immaculate engine performance played a vital role in the accuracy of his cornering lines and the consistency of his lap times which made him so dominant.

The final factor in Rossi’s superb 2001 campaign – 11 victories from 16 races – was a mid-season performance boost. 

“We changed a lot after the summer break: shocks, suspension links, geometry, engine bits, everything,” adds JB. “All that allowed us to make big improvements in handling, through suspension and geometry.”

Rossi’s only title rival Max Biaggi had a strong midseason on his YZR500, at one point reducing his countryman’s championship lead from 46 points to 10. But once HRC and JB had further improved the NV4B, Biaggi had no chance.

Remarkably, Rossi believes he didn’t fully master riding a 500 until the penultimate race of his two seasons with the two-strokes. The moment was his 10th victory of 2001, at Sepang, where he enjoyed himself sliding and spinning his rear tyre on the hot, greasy asphalt. 

“In Malaysia I finally arrived to go very fast with the 500,” he said later.

Although the NSR was without doubt the best bike on the grid, earlier versions of the bike certainly weren’t. All NSRs of the 1980s were evil pieces of machinery, to a greater or lesser extent. The crucial year for the NSR was 1989, when Eddie Lawson defected from Yamaha to Honda, working with legendary engineer Erv Kanemoto.

During that summer Lawson, Kanemoto and HRC did ground-breaking work on chassis stiffness, using at least seven different frames and swingarms during the 15-race series.

“We were doing so much testing and trying so many things, so HRC started to understand what needed to be done next,” said Kanemoto. “Since then we’ve seen the shape of frames and swingarms change, so that when the bike is over on its side the rigidity is reduced, but when bike is upright it’s very rigid.”

The knowhow gained during 1989 also put HRC on the correct road with engine development. Lawson’s feedback convinced HRC to use a new cylinder-firing configuration for 1990. The even-spaced 90-degree firing configuration of 1989 was replaced by a 180-degree configuration, which fired cylinders in pairs to improve traction. This was the first step towards the game-changing big-bang engine of 1992.

“During 1989 the engine character caused a lot of what people thought was a handling problem,” added Kanemoto. “We got a big gain with the 180-degree engine, because the power hit wasn’t so abrupt, so the rider could start to open the throttle when the bike was leaned over. HRC had their eyes opened – they realised that this handling thing isn’t just the chassis, it’s engine character too.”

The big-bang concept was so important to motorcycle racing that it’s used in MotoGP four-strokes to this day.

HONDA RC211V

2002-2003

Honda made everyone else look a bit stupid at the start of the four-stroke MotoGP era. While Japanese rivals Suzuki and Yamaha built 990cc four-stroke engines and crammed them into revised 500 chassis, HRC designed an entirely new motorcycle. No wonder it won 29 of the 32 races that comprised the 2002 and 2003 seasons.

Even now many paddock people consider the RC211V to be the greatest grand prix bike of all time. The machine was Honda’s first all-new GP bike of the 21st century, hence its designation, which stands for Racing Cycle, 21st century, Model 1, Vee engine.

The RC211V was a completely integrated motorcycle born out of a freshness of vision and some very clever thinking. During its design process, HRC designers adopted new strategies to various problems that had become the accepted norm during the final years of 500 racing, like chatter and high fuel loads in the early laps of a race.

Rossi didn’t like the bike when he tried the first prototype at Suzuka in August 2001, but by the first race of 2002 the V5 was better than an NSR500. Once again he won 11 of 16 races, smashing race records here, there and everywhere. At Valencia the RC211V was 65 seconds faster than the 500cc race record, an improvement of two seconds a lap.

There were numerous reasons the RC211V was such a big step forward. First of all, the easy-going nature of a four-stroke engine.

“The four-stroke is easier because when you’re mid-corner on a 500 you have zero power,” explained Rossi’s crew chief Jeremy Burgess. “When you open the throttle from the lowest rpm point, say 6000rpm, the 500’s not making any more power than a streetbike, but then it suddenly builds to 190 horsepower. 

“On the four-stroke you touch the throttle mid-corner and you’ve already got tons of torque, so from that point you can open the throttle fairly quickly, whereas with two-stroke you have to be really careful how you open the throttle. Plus the engine is just bloody fast – there’s so much power that you can just drive past a 500, even on a short straight.”

The RC211V’s excellent combustion came from a cylinder design and bore/stroke ratio taken from the RC45 superbike, plus a big-bang firing configuration and very trick throttle bodies, which gave friendly power delivery and a remarkably flat torque curve.

“A flat torque curve means you can spin up the tyre at a particular throttle opening, and although the rpm comes up the torque doesn’t come up with it,” said a rival MotoGP engineer. 

“Then if you hold a constant throttle the same amount of torque that broke the tyre loose is still there, so you just hold the throttle and the bike comes back into line. That’s what riders of the RC211V always say: they can get sideways, then get back into line whenever they want. 

“Honda’s big thing has always been the flat torque curve. It was the same with two-strokes. Their strongest point with the NSR500 wasn’t so much rpm or horsepower, it was purely engine character. I think they understood that much earlier than anyone else.”

RC211V project leader Tomoo Shiozaki’s other big thing was mass-centralisation. That’s why he chose a narrow-angle 75.5º angle for his vee engine, around which he did everything possible to concentrate mass in the centre of the motorcycle. This made the RC211V easier to handle and therefore easier to ride at the limit.

Fuel-tank positioning was probably a big part of this concept. For decades fuel tanks had been mounted above the engine, atop the frame. The RC211V led the way in this important design change, carrying one third of its fuel below the rider’s backside. This not only centralised mass, it also delivered a major improvement in handling during the early stages of races when riders of more conventional motorcycles battled a heavy fuel load carried at the top of the bike. HRC estimated the RC211V reached 90 percent of its performance in the first laps, while the NSR500 managed only 70 percent.

The rear suspension design (with both ends of the shock anchored to the swingarm) also helped centralise mass, at the same time reducing chatter.

Frame design also pointed the way to the future, with smallish beam sections and very deep, triangulated engine hangers. This gave excellent longitudinal stiffness, for braking stability, while allowing reduced torsional stiffness, to make the frame more flexible at high lean angles, thereby reducing chatter and making the bike easier to control during rear-end slides.

“Sliding a bike is easier if the chassis is not totally rigid, not so snappy,” explained Shiozaki.

Both Rossi and Burgess grew to love the RC211V. 

“The bike is incredibly neutral,” said Burgess. “Sometimes we went to two or three different tracks and didn’t even change the fork springs. You couldn’t do that with the 500 – if the front end wasn’t working, the bike wouldn’t go fast. 

“The four-stroke’s engine braking helps turn the bike, so we’ve had no trouble with the front, whereas we were always working on the 500’s front end with Valentino, and Mick particularly.”

Although the V5 never gave Rossi the buzz of riding a 500 – on which the tiniest mistake might flick him to the moon – he did enjoy the bike. 

“When you ride the RCV it is great fun and when you ride it at 100 percent it’s like sex!” he said.

YAMAHA YZR-M1

2004-2010 and 2013-present

Yamaha’s YZR-M1 is the bike that transformed Rossi from man to superman. Ruling MotoGP on the best bike was one thing, but dominating on what had been the worst bike was something altogether different.

Rossi agreed terms with Yamaha in August 2003, a few weeks before he wrapped up his third-consecutive premier-class crown with Honda. At that time the M1 was a disaster. The bike didn’t score a single victory during 2003 and took just one podium. During the same time the RC211V took 15 wins and a total of 39 podiums. This was the scale of the challenge facing Rossi, crew chief Jeremy Burgess and Yamaha’s racing chief Masao Furusawa.

In fact they fixed most of the bike’s problems during Rossi’s first outing on the bike, a three-day MotoGP test at Sepang in January 2004. The combination of Rossi’s feedback and Burgess’s problem-solving skills cured the chassis ills, while Furusawa’s big-bang M1 engine solved the engine’s power-delivery issues.

During 2003, the M1’s scariest problem had been locking the front tyre into corners. During eight months of racing and testing no one had been able to fix this.

Rossi soon encountered the problem, reported to JB, who checked the data. Quickly they worked out that the engine-braking software was all wrong – it was accelerating the bike into corners! 

Also, the fairing was jamming against the front mudguard and the bike was difficult to turn. The solution to these problems was simple: raise the bike. Not by a few millimetres, but by 15mm!

Furusawa’s cross-plane crankshaft engine was the next revelation, because it mimicked the rider-friendly and tyre-friendly performance of the RC211V. Rossi immediately understood this was the way forward, because the more easy-going engine configuration allowed him to spin and slide the rear tyre in a more controlled way.

“Sincerely, I expected bigger problems, but more or less the bike is okay,” said Rossi at the end of the Sepang tests. “It has some things that are less than Honda, but also some good things. Basically it’s not so bad.”

Rossi and the YZR-M1 won first time out at Welkom in April 2004, but the bike remained a work in process throughout that season. The 2005 M1 was the real deal, helping Rossi to 11 wins, equalling his feats with the NSR500 and RC211V.

The M1’s greatest strength has always been its neutral behaviour and user-friendliness. It’s never been the most powerful bike on the grid. Indeed during 2007, when Casey Stoner and Ducati dominated the championship, Rossi was already suggesting that Yamaha should build a V4. But V4s never handle as well as inline-fours.

At the end of that season Rossi threatened to walk from Yamaha if they didn’t turn things around after losing the title in 2007 and 2008. The threat worked because the 2008 M1 was the best bike on the grid. Power was up by 12 percent, but the giant leap was its electronic control systems, with cutting-edge vehicle dynamics software that calculated lean angle, tyre contact patch, centrifugal force and delivered exactly the right amount of torque at any lean angle, regardless of how much throttle the rider used. The system was also predictive, like Ducati’s, so it was always one step ahead of the rider, making tiny adjustments as and when necessary.

Rossi won the title in 2004, 2005, 2008 and 2009, then Jorge Lorenzo took the crown in 2010, 2012 and 2015. All through this time the M1 was probably the best overall package in MotoGP.

Two changes ended the M1’s domination: the arrival of Marc Marquez in MotoGP in 2013 and the switch to spec Magneti Marelli software and spec Michelin tyres in 2015.

“Our bike is still well balanced, but we ride more metres to make each corner,” said Rossi in 2013. 

“The M1 has the behaviour of a more normal bike. We are very fast in longer corners, but Honda have something special for tighter corners. They are able to make a different line – their bike turns very well, so they can cut the inside kerb. They go tighter and then they can use the acceleration.”

The arrival of Michelin tyres only exacerbated the M1’s problems. High corner speed had been a strong point, but not anymore.

“Our negative point is that our bike needs more lean angle to make the corner,” said Yamaha motorsport manager Kouichi Tsuji in 2018. “So we use the edge of the tyre more, so edge grip drops down and the bike doesn’t do what the rider wants it to do.”

Yamaha’s refusal to follow the lead of Ducati and Honda – hiring Magneti Marelli technicians to help them find their way through the labyrinth of the spec software – also contributed to the factory’s longest victory drought since it entered the premier class in 1973.

“If we had also done this two years ago maybe we would be at a better level now,” said factory engineer Takahiro Sumi at the end of 2019. 

Despite just 13 wins from the past four seasons, compared to 30 in the previous four, Rossi ended last year convinced that Yamaha is getting there.

“Yamaha is finally starting in the right direction,” he says. “They start to do clever things, so the situation is very much changed compared to the last two years.”

   Words Mat Oxley Photography Gold&Goose and AMCN Archives