Aprilia’s MotoGP history: This is the Italian factory’s story, all the way from the RSW500 two-stroke twin to today’s 90-degree V4 RS-GP.

1994-2000

• RSW500: 500cc V-twin two-stroke

The idea of the RSW500 was born at the 1993 British GP, where the 500 race was just 0.37km/h faster than the 250s, thus Aprilia believed it could get good results in the premier class with a big 250. Its first 500 – an RSV250 bored and stroked to 410cc – arrived at Jerez the next year, where it qualified on the second row.

By 1999, the RSW was close to a full 500cc and scored its first podiums, beating a bunch of faster but more unwieldy 500 V4s. The following year Jeremy McWilliams came within 0.9 seconds of winning the British GP at Donington Park, after a long battle with V4 riders Valentino Rossi and Kenny Roberts Junior.

“The 500 twin was an awesome little bike – it was so light and so good for corner speed,” McWilliams recalls. “I think we could’ve got better results at tighter circuits like Donington and Sachsenring, where we didn’t make the most of it with the gearing.”

“It had so much mid-range, maybe even too much torque, so it wheelied everywhere, so instead of gearing it short and using all six gears at Donington, we should’ve geared it higher and used first to fifth or second to sixth, so it didn’t wheelie so much.”

Inevitably, the twin’s biggest problem was horsepower. The final iteration made 140hp, about 60 less than the V4s at the time. In races, this made life difficult for the rider because although he had more corner speed than the V4s he couldn’t use that advantage if a V4 came past on the straight and blocked his line.

“The V4s would always out-drag you to the next corner, so you were always playing cat and mouse with them,” McWilliams adds.

The 500 project ended after the 2000 season, when Aprilia started work on the RS Cube.

2002-2004

• RS Cube: 990cc inline triple cylinder, four-stroke

Aprilia joined the new 990cc MotoGP class in 2002, its inaugural season, with a radical inline triple, the company’s first four-stroke GP bike. Using just three cylinders instead of four or five (like its rivals) allowed the RS Cube a weight advantage, but that wasn’t enough to make it a winner.

The Cube was radical because it was the first MotoGP bike with pneumatic valve springs, ride-by-wire throttle and carbon clutch, thanks to input from British Formula 1 engineers Cosworth.

The machine was certainly fast – at Mugello 2002 it became the first MotoGP four-stroke to break the 200mph (320km/h) barrier – but it was a beast of a motorcycle.

“It wanted to kill you everywhere,” says Jeremy McWilliams who rode the Cube in 2004, its final season. “It made lots of horsepower but in all the wrong places. I think it broke every one of my ribs twice that year.”

“It had this really weird torque curve, so the engineers tried to fill in the holes in the curve with clever fuel and torque maps. It started making torque at around 9000rpm, then it dropped away and then there was a really sharp torque peak at 12,500, which sent the bike sideways and fired you on your nose.”

Formula 1 is all about peak horsepower, because drivers have so much grip they can stamp on the accelerator, while MotoGP is mostly about part-throttle performance, because there’s so little tyre on the ground. Cosworth know lots about F1, and not so much about MotoGP.

“The engine was basically three cylinders from an F1 engine [2002 F1 cars had 10-cylinder three-litre engines],” McWilliams continues. “It had a very light crankshaft, so it had too little inertia, so as soon as you opened the throttle the rear tyre would spin. We were always asking for more inertia, but they said there was no room in the engine.”

McWilliams was also a crash-test-dummy for ride-by-wire throttle technology.

“At Sachsenring I got flicked off when I was using about 10 percent throttle and it suddenly went to 80 percent. Aprilia thought that came from outside interference, so they wrapped the ECU in tinfoil.”

Aprilia never scored a podium with the Cube, so they tried to get noticed in different ways.

“What they wanted was the fastest top speed and the loudest motorcycle, that’s why they ran twin megaphones. Everybody still talks about how amazing the bike sounded but it didn’t sound so good sitting on it! The reverberations went right through you. It was an absolute f***ing beast of a motorcycle!”

2012-2015

• ART: 1000cc V4 four-stroke

Aprilia stayed out of MotoGP for almost a decade after its RS Cube project was shut down. It returned in 2012 with a bike specifically built for MotoGP’s new class-within-a-class CRT category, which allowed teams to use bikes powered by superbike engines, to reduce costs in the wake of the global financial crisis.

ART was short for Aprilia Racing Team and avoided this hybrid machine from being considered a proper Aprilia MotoGP bike. Despite its budget spec, the RSV4-powered ART scored some decent results.

“It was one of most fun bikes I ever rode,” says Aleix Espargaro who raced an ART in 2012 and 2013, scoring 14 top tens. “If I had to define the bike in one word it would be agility, it was super-super-agile. The first time I rode it I told the engineers that it was a 250 with a strong engine; it had the DNA of an Aprilia 250.”

“The bike was also very low-cost and not so different from a bike you could buy in a shop, just carbon brakes and a better frame. At that time many journalists asked me if the difference in money between a CRT bike and a real MotoGP bike was worth it and I said, ‘Mmm, maybe not’.”

In fact Espargaro much preferred the ART to Ducati’s Desmosedici MotoGP bike he’d ridden in 2009 and 2010 (he returned to Moto2 for 2011).

“Going from the Ducati to the ART was like going from a boat to a bicycle! At that time the Ducati was super-powerful but unrideable. I had no idea how to ride that bike, it had zero turning.”

2016-2019

• 75º RS-GP: 1000cc V4 four-stroke

Aprilia quit MotoGP at the end of 2004, when the company was bought by Piaggio. In 2012 the racing department made a low-key return with the RSV4-powered ART machine, then officially returned in 2015 with its first RS-GP, still powered by the RSV4 engine, with gear-driven camshafts and pneumatic valve springs.

Thus 2016 was Aprilia’s full MotoGP restart, with a fully prototype engine, a 75º V4. A narrow-angle vee makes lots of sense because it’s a shorter engine, which allows a more compact motorcycle. On the other hand the engine vibrates more, plus there’s not enough room between the vee for the fuel injection and throttle bodies, so the motorcycle becomes taller. You win some, you lose some.

Espargaro joined Aprilia in 2017, after losing his Suzuki ride, and was never happy with the 75-degree RS-GP.

“It was impossible because it was like riding a 500,” he says. “The problem was that the engine had no torque at the bottom and it finished very early, at 17,000rpm. The bike had good agility, but the engine made it very difficult to ride, especially at low-grip tracks, where the super-tricky power delivery made it so bad.”

“We worked a lot with the chassis, but all the problems came from the engine. There was always a lot of vibration, which gave a lot of chatter and made the bike super-nervous on the brakes. You had to be super-precise, so in the wet it was a nightmare. From 2017 to 2019 we made no f***ing progress at all.”

2020 to present

• 90º RS-GP: 1000cc V4 four-stroke

Aprilia’s moment of MotoGP revolution came in 2019, when parent company Piaggio decided that it must go big or go home. In other words, start spending proper money on its MotoGP project or quit.

The result of that change of philosophy was a huge technical advance, when the Noale factory created its 2020 RS-GP, the first iteration with a 90-degree V4 engine. Switching from a narrow-angle vee to a wider-angle vee changed everything and made good sense, because Ducati and Honda were dominating with their own 90-degree V4s.

Aleix Espargaro, who scored the company’s first MotoGP victory at this year’s Argentine GP, remembers the moment he first rode the new bike, during 2020 pre-season testing at Sepang.

“I did three laps, came into the garage and I was crying,” recalls the 32-year-old Spaniard, who joined Aprilia in 2017. “I told the engineers, ‘This is the best bike you ever made, it’s crazy, unbelievably good!’ I was crying because at the end of 2019 I was thinking of retiring, because with the old bike it was impossible to be fast.”

“Actually we couldn’t start the new bike at Sepang because the starter didn’t have enough power to turn over the engine, so we closed the garage door and started the bike using a scooter: full gas with the scooter’s rear tyre against the RS-GP’s rear tyre!”

The real reason Aprilia couldn’t start the bike was the Covid pandemic which hit Italy so hard in the early months of 2020.

“The factory was closed because of Covid, so those Sepang tests were like our engine bench test,” adds Espargaro. “Then when the Qatar GP was cancelled all the bikes and equipment were in their flight cases in Qatar, so we couldn’t work on anything. The engineers were very worried because we couldn’t test anymore, so they reduced the redline by 500pm, just to be safe,”

At the same time, MotoGP introduced emergency cost-cutting measures, banning engine and aerodynamics upgrades, so Aprilia raced throughout 2020 with its prototype engine and aero. That’s why the bike didn’t excel until 2021, when Espargaro scored the company’s first four-stroke MotoGP podium at Silverstone.

“In 2019 I told the engineers that even if they gave me more power with the old bike I wouldn’t be able to use it, except on the straights, because the bike was so difficult to ride. When I rode the 2020 bike I said, okay, this is ready for 10 or 15 more horsepower, because the power delivery from the bottom was super-smooth.”

The 2020 RS-GP was different because its engine was longer and lower, but most important was the 90-degree V4’s improved horsepower and torque (and therefore improved negative torque, which is so important during braking and corner entry), because a 90-degree vee has perfect balance, so it can be tuned more aggressively.

“Now I have a lot more torque at the bottom and a lot more rpm at the top, which makes a huge difference, because even if you change the frame and swingarm of a racebike, it’s all about the character of the engine.”

“Changing the angle of the vee completely changed the bike – it was easier to ride, the throttle connection was clean and there was no vibration. The engineers told me they changed the vee angle because even after two or three years they couldn’t find one more horsepower with the old engine.”

The RS-GP also handles well, so well that it has the rider-friendly character usually enjoyed by inline-four MotoGP bikes. Aprilia’s chief engineer Romano Albesiano won’t reveal how he makes this happen, but he’s been doing this job for a while – he started out as a chassis engineer on Cagiva’s 500cc GP bike in the early 1990s.

“Then in 2021 we made a big improvement with the aerodynamics, so we can put the power to the ground without wheelspin and wheelie,” Espargaro continues. “The aero helps you find a compromise between straight-line speed and downforce in corners, but it’s not easy. Aprilia has spent a lot, a lot of money in the wind tunnel and it was worth it because the bike is fast in sixth gear but still the turning downforce is very good.”

Halfway through this season Aprilia introduced a ground-effect lower fairing, which increased grip in faster corners

“It gives me more stability,” says Espargaro. “And when you have more stability you can squeeze the tyres into the ground more and push harder.”

And never was that more apparent than at Assen, when he spun his way out of the gravel trap in 15th place and raced like a man possessed through to fourth by the flag.  

WORDS // MAT OXLEY
PHOTOGRAPHY // GOLD&GOOSE