Guest Blog: Mat Oxley - Why V4 MotoGP bikes are better in battles

MotoMatters.com is delighted to feature the work of iconic MotoGP writer Mat Oxley. Oxley is a former racer, TT winner and highly respected author of biographies of world champions Mick Doohan and Valentino Rossi, and currently writes for Motor Sport Magazine, where he is MotoGP correspondent. We are featuring sections from Oxley's blogs, which are posted in full on the Motor Sport Magazine website.


Why V4 MotoGP bikes are better in battles

2020 Austrian MotoGP Insight Part 3: V4s have been the dominant force for years and not only because they make more power. Plus, has KTM built the perfect V4? And Honda’s toughest start in decades

Last weekend’s Austrian GP was the perfect illustration of the difficulties that riders of slower, better-handling inline-four MotoGP bikes face when they are fighting with rivals using faster, poorer-handling V4 machines.

V4 MotoGP bikes make more horsepower because a V4 engine has a stronger crankshaft, less vibration and fewer pumping losses, while inline-four MotoGP bikes are more user-friendly in corners because an inline-four engine has a longer crankshaft.

Some of Sunday’s race was a straight fight between two Suzuki GSX-RR inline-fours and two Ducati Desmosedici V4s. The V4s had the advantage on the straights, while the inline-fours had more speed through the corners, if they had the room to use it.

Yamaha was in a much worse state than Suzuki at Red Bull Ring. While the GSX-RR reached 193.8mph on the run into Turn Two, just 1.6mph slower than the Ducati, the YZR-M1 was 3.7mph slower. These might seem like tiny differences, but MotoGP is so close now that any deficit in any area of performance is a big problem.

Two Yamaha riders qualified on the front row, because M1 riders can cut super-fast qualifying laps on a clear track. But when they get boxed in by faster V4s in a race they’re in trouble.

What happened to Franco Morbidelli on Sunday was an extreme example of this. Johann Zarco used his Ducati’s superior speed to pass Morbidelli, then blocked his line. And not necessarily on purpose, because by taking a tighter line through the kink his bike naturally drifted to the right.

(It’s also worth adding here that braking in someone’s slipstream is a nightmare. Just as the vacuum created by the leading motorcycle helps the chasing motorcycle accelerate faster, so the lack of wind resistance makes the chasing bike decelerate slower. This is one reason why riders using a slipstream on a straight always move to the left or right of the leading bike when they brake.)

Anyway, back to the story. There are numbers that prove that inline-fours work better alone than in a battle: in the 50 races prior to this season inline-fours fared much better in qualifying than they did in races, taking 17 pole positions against six race victories.

Read the rest of Mat Oxley's blog on the Motor Sport Magazine website.

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Comments

With two previous articles, Why are MotoGP V4s faster than inline-4s? and Why inline-four MotoGP bikes handle better than V4 MotoGP bikes, about the same topic this year alone, was this one really necessary?  I understand Mr. Oxley added the bits about KTM finding a mix of V4/i4 performance and Honda's current predicament, but still...

Back in the 2 stroke days the lap times were very close at some tracks between 250/ 500, so Aprillia & Honda made 'big 250s' to compete in 500. During practice/ qualifying the 410/ 500 V-twins could run quick lap times on a clear circuit due to their higher corner speed, but come race time the V4s would baulk them in the corners then disappear on the straights. Different bikes, same problem. Mixed class club racing is the same, unless you can do a Jorge. 

Thanks Mr. Oxley.

I found Dovizioso's comments about the KTM in the pre race presser very interesting. Three different riding styles and all are fast. Don't intend any disservice to Lecuona, probably Dovi hasn't seen him on track yet.

The results in WSB would seem to dispel this, although maybe the rev limit evens the playing field. If the Ducati could rev to the moon as intended perhaps the results would be different. As stated the Suzuki is almost there top speed wise, so maybe it's just a Yamaha thing, in 500 the Honda always had the most engine, the Yamaha the sweetest chassis until Suzuki caught up, all were V4s. It's interesting that the first Suzuki MGP bike was a V4 & is now an IL4, so are Yamaha & Suzuki thinking about the closer links and trickle down tech from MGP to road bikes, whereas HRC just thinks about what is the best configuaration for the current rules? There's a quote via Dennis Noyes isn't there "Honda=NASA, Yamaha=Pure Marketing".