Michael Scott | July 19, 2017
Race engineering is to a large extent a matter of fashion. Or to put it another way (as former world champion and revered crew chief to Kenny Roberts Sr. Kel Carruthers told me many years ago) “what worked last year, plus a few percent.”
In this way, in the years of those amazing unrideable 500cc two-strokes, everyone ended up with a V4 engine. Everyone up front, anyway.
In modern MotoGP, some of it is written in stone anyway. Four is how many cylinders you have, 81mm is the widest the cylinder bore can be. With these restrictions it was goodbye to the marvelous sound of Honda’s old 990cc V5 and Aprilia’s raucous inline triple. But it’s a little surprising that there is still some variety in the engines on the grid.
Not a huge amount, but with six different bikes, four are V4s, but not identical, while two are straight fours.
Honda and Ducati have 90-degree V4s, Aprilia’s has angle of 75 degrees, while the KTMs seem to be somewhere between the two.
Yamaha and Suzuki run inline fours that are essentially pretty similar. Both have cross-plane crankshafts and off-beat firing intervals, turning them into virtual V4s, but in a different, potentially lighter and definitely more compact package.
They all race against one another with varying degrees of success, but it is important to note that the margins between winner and also-ran are often very small indeed, smaller than the differences between the machines, and smaller also than the difference in the status of the various factories.
The biggest differences in all these areas are on display from the newest arrival. In a world that tends towards imitation, KTM is absolute heretics. They are so far off the page in so many areas that the fact they are on the same final lap as the winner is already impressive, let alone the fact that one or both of their riders very frequently scores points.
As Aprilia and Suzuki found out over the last year or two, it’s not supposed to be that easy.
The heresy starts in the Austrian factory’s whole approach to the world championships. KTM is the only factory represented in all three classes. Admittedly they are having an unusual struggle in Moto3, probably because of a diversion of resources to MotoGP, and admittedly their Moto2 entry only goes as far as the chassis, since all the unfortunate riders in the millstone middle class use the same boat-anchor engines. But the point is clear: they are the only factory to have a clear ladder for a young rider to climb, from a start in Moto3 to the pinnacle of MotoGP. Lucky rider. Go, Brad Binder.
Technical heresy is most plainly obvious in their bright orange steel-tube chassis. I mean—steel tubes? Nobody uses them any more, even for sub-frames. Not even Ducati—although back in 2003 when they first arrived the Italians started in the same way. Back then, I asked then race chief (now big boss) Claudio Domenicali if he thought the material appropriate. He gave another of my favorite racing quotes: “That is like asking the host if the wine is any good.”
Another outward deviation is also plain to see—the front forks. Everybody else uses Ohlins suspension. Even Honda long since abandoned their own close associate Showa to go with the crowd. KTM, however, declined to jettison their own subsidiary company WP (formerly White Power), and are suspended by WP front and rear.
Less easily seen is the V angle, and more importantly the direction of rotation of the crankshaft, both of which KTM keeps to themselves. But it seems the crank spins forwards, the opposite of the direction taken by all the others, which has implications both gyroscopically and in terms of torque reaction. Honda used to do the same, but reversed spin direction last season, and is still trying to make it work,
Given this independence of thought and action, it’s hard not to admire what KTM has achieved so far in the premier class. But perhaps we should wait and see what happens next. The margins may be small, but they are very hard to bridge.
And KTM has a MotoGP history that is less than marvelous—an ill-fated and under-budgeted attempt in 2005, supplying engines to an equally cash-strapped Team Roberts. The V4 engine (designed, as is the current one, by ex-F1 engineer Kurt Trieb) was enormously powerful, but far from reliable and very hard to manage, thanks largely to the stab at independence with their own electronics. An opportunity for failure no longer available, thanks to control electronics.
Anyway, KTM pulled out of the deal midway through the year, leaving the popular Team Roberts on its uppers, and a bad taste in the mouth.
Let’s hope this time will be different. CN