I tested a (worn out) 30mm 2011 otk vs a 2013 32mm (2 races old) a few years back.
Both were setup exactly the same with the engine on the 30mm being 0.3 seconds faster.
The 30mm was faster but only a few tenths of a second, (0.7 fastest lap diff) if it wasn’t dead it would have been more for sure.
I liked the way the 32mm drove more, it was extremely direct/responsive compared to the 30mm. But that also made it harder to drive because you are balancing on finer margins.
In the notes of that day I kept describing it as “really sharp” to drive.
The 32mm couldn’t take kerbs at all compared to the 30mm, but the wear on the 30mm probably has had a huge impact on this
There were no big differences in terms of over/understeer or hopping.
Testing was done on mojo d5’s with a rotax senior engines
I just stumbled across this thread where my dissertation report is being discussed! Awesome to read your thoughts on it. It´s been quite some years now. I agree that it´s not perfect and it leaves a lot of questions, but it was a start in a field that is filled with a lot of believes and not a lot of data. Even though the project was partly sponsored by SSAB, the manufacturer of Docol, we saw that Docol gives a significant improvement in durability, at a similar performance. E modulus off almost all ferrous steels is the same, so as long as you keep the same dimensions and wall thickness, driving performance will be very similar.
There may not be much motivation for companies that own the market to bring longer lasting karts to market. For companies that do not the motivation is to get more of the market. If it works at all then there is motivation for the market owners to keep their market share. I think in the end if there is a better solution, eventually there is benefit for some company to bring it to market
Resistance against plastic deformation. A chassis in Docol R8 (or any other high tensile strength steel) will hold its shape much better during a season than DOM chromoly.