If anybody tells you it is easy to make modern day Superbikes truly competitive with fixed tech rules that are identical for every bike, smile warmly and move on to a more stimulating, reality-based conversation. Possibly the single most difficult thing to do is make sure the final on-track performance of what started out as commercial products in the market place, all with their own unique marketing USPs and familial DNA helices, is to design the final tech rules. After all, some donor bikes are still relatively cheap and low-tech and some are sold right on the forty grand limit for eligible WorldSBK machines, complete with an electronics suite fit to control the International Space Station. Or even a design concept that is MotoGP-driven, rather than coming with an extended warranty requirement in the original engineering brief.
Enter a plethora of performance rules for WorldSBK, which extend to cost-capped parts and approved racing parts, which can include concession parts, as one profound balancing rule element if your bike qualifies. But all of these operate under the catch-all of the ultimate balancing rule - Maximum Rev Limits.
There, I capitalised the initial letters, to show how significant this one can be.
World vs WorldSBK
WorldSBK operates a differential rev limit system, based from the outset on the real world engine performance of the stock bike. This rev-limit philosophy operates not only between manufacturers, but also between each manufacturer’s homologated models. So the superseded (but still homologated) Honda from 2019 has a different upper rev limit than the more radically designed new stock bike’s homologation. That 2020 model simply revs higher than the old one does, even before a single head gasket has been unsealed, and so it will start with a higher permitted rev limit.
You could still run a Ducati Panigale V2 if you so wished in WorldSBK, but beyond that remote possibility all WorldSBK machines are now four-cylinders of some kind, with the same 1000cc engine displacement. That does simplify the job of the FIM and Dorna to control ultimate engine performance, but given that not all WorldSBK machines are created equal on the street, the data that they use to bring forward the max revs at the beginning of each homologation is based on measured performance of each machine.
The most recent rev-limits have just been published. In essence the first-time rev balancing rules for a new model are best explained by a direct quote from the FIM rulebook. “The initial rev limit will be the dynamometer measured rev limit of 3rd & 4th gear averaged, plus 3% or 1100 rpm above the dyno measured max horsepower rpm of a production machine, whichever is lower.”
So that’s the basic starting point when a new bike comes along. The decision to increase or decrease peak revs bike-by-bike is arrived at via an algorithm, based on real results and other factors. After a cycle of three rounds of the championship the powers-that-be use peak rev limit changes, usually in 250rpm increments that can be up, down or no change, as a dynamic way to balance the championship’s competitiveness. Honda got 500rpm more in one go once, so there is flexibility built in beyond a rigid 250rpm single step, and the tech ref’s rule is final anyway.
What is involved in the algorithm is startlingly complicated to all but the most case-hardened metal heads. It’s to be found in section 18.104.22.168 of the new FIM rulebook, if you really must… Get the kettle on and put the phone on silent if you wade in that deep.
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