The Circuit de Catalunya features a mix of fast and slow corners, a long straight and a variety of elevation changes. As a result, it is a popular testing venue (more F1 than MotoGP nowadays), aided by the usual pleasant winter weather. Happily, without the aerodynamic constraints of the F1 cars, the motorcycle course had a slightly different sector 3 without the final chicane, leaving in a sweeping right. Overtaking is much easier on two wheels, Valentino Rossi pulled off a spectacular last-lap dive on Jorge Lorenzo in the final turn of the 2009 race to deny the Spaniard a home victory. Here's how to maximise the setup on your bike to emulate those great riders.
Tyres - Front (Medium) - Rear (Hard)
In qualifying trim you can always run a soft front and rear for pretty much any track the MotoGP calender visits. It's the race setup that matters the most. With the pressure and strain the high speed corners can put on your tyres it is important to make them last. Chances are you will apply quite a lot of power through the rear wheel quickly. To avoid your tyre being torn to shreds within the first few laps go with a hard rear. Since Catalunya isn't that front limited and there aren't that many tight corners you can get away with a medium front rear. If you are conservative with tyres then a soft front could even be an option to set you apart from the crowd.
The standard bike setup for a lot of the MotoGP bikes is a tad slow leaning and can understeer easily on track with high speed, high rotation corners like Catalan is famous for. To combat this you increase your preload on the front and rear. A taller bike also gives you a slightly higher lever to manoeuvre the bike through faster corners. Since you'll be putting on the power often round Catalunya it's vital you don't high-side the bike and fall off. This is quite a simple fix, lower your rebound on the forks shock absorbers and increase compression, this makes the bike more stable.
Combined with the steering adjustments I will come to shortly, this makes the bike responsive enough for the corners but gives you more room for error in applying power. Finally, increase the rear springs hardness for a more precise rear end while maintaining front end stability, you will need this through sector 3.
Increasing your rake and trail makes the bike a lot more stable for you newer riders but less responsive so you may need to adjust your braking zone slightly earlier if you want a high-high rake and trail. Since this track is relatively balanced in that department, with a mixture of tight high acceleration corners and fast sweeping bends, a compromise is necessary. The reason I went slightly lower with the trail is because as the trail is increased this adds to the potential understeer and slow responsiveness Catalunya breeds.
The braking zones can be severe here. It's not a very flowing track for a MotoGP bike, especially going into turns 1, 5 and 10. So having your brakes as powerful as possible (340,220) will always help a new rider. Modulation is something you don't really need to worry about here, as it's all about making sure you can scrub off the 200mph speeds in time to turn the bike in without sliding off or getting a dose of understeer from turning in late and over tilting the bike.
This is a difficult one as ultimately this varies on how confident you are as a rider and which assists you are running. Personally I think TCS is more important than the other settings here as with the amount of high-speed applications of throttle mid corner you need to do having a decent amount of Traction Control helps manage this. I have engine braking at the maximum here because as mentioned earlier you need everything at your disposal at this track to help slow the bike at those high braking zones. With the setup I have shown you here you shouldn't need too much Anti-Wheelie especially through sector 1 and 2, but as with traction control be careful with the throttle application.
This setup was tested with normal physics and a semi-auto gearbox. It may need tweaking for your particular level of assists and riding style. Good luck, and see you on the timesheets!