First of all I know I can assign buttons on my wheel to increase/decrease Brake balance whilst in the car. I would really like to get into this side of driving (like Schumacher does during GPs) Can someone kindly explain the benefits of this in terms of what kind of settings you would need for certain corners? Is Schumacher increasing or decreasing before a tight corner? What is a driver looking for with his brake balance over the course of a lap? I usually adjust my brake balance 60/40 to the front of the car and this is a comfortable set up for me, would I tweak it to the rear for certain corners, and tweak it forward for the big stops? If anyone can explain the basic principle of this, I can start my Schumacher practise!!
I'll leave it for someone else to explain brake bias adjustments, but modern F1 is polluting racing with artificial situations which makes people believe this occurs in all forms of racing. In modern F1 the brake bias is primarily adjusted because the kers system affects the brake bias when harvesting, so they need to compensate for that.
Schumi is the best driver in F1 over the last 30 years hands down. Give this a read. The guy just flat out knew what the car was doing. http://www.dellanave.com/files/f1racing.pdf
Didn't read that Schummi thing, but for those that are not sure, brake bias is normally adjusted to compensate for setup and condition changes, not necessarily for any specific corner. Consider this, your car is setup and tested with 20L of fuel, but you start the race off with 60L, obviously the cars balance is a little off from what you have setup so braking may not be optimal. By being able to change the bias on the fly, the driver can compensate and have a better lap time when the tank is full, or near empty for that matter. Also consider that maybe the car was setup for dry and the track is a little damp. This might be a time when changing bias will help you stop better than what the original setup allowed for. As to specifics, I couldn't tell you as I don't usually adjust while I am driving unless I am having issues with one axle or the other locking wheels, then I adjust until I get back into the garage where I make the change permanent. I am just not as on the edge as a lot of you aliens out there, so changing bias will likely not help me as much. hehe.
At least I also change the bias in some longer races if I happen to get uneven wear on the tyres. In some cars the fronts are under more stress and tend to give out sooner, so to prevent the wheels from locking up I might move the brake bias back a bit. The reverse naturally works if the rears start to get slippery and the car becomes unstable while braking during the race.
Why do we need to adjust brake balance? We want the brake balance to be such that we maximize the available braking power of all tires and give the driver the best possible control of the car through the entry of a corner. The best brake balance setting depends on a several factors and varies between corners depending on their profile. Brake bias adjustments are usually needed in corners with different amount of weight transfer and grip levels. Different grip levels in different sections of the track will cause different amount of weight transfer to the front tires. The main rule here is the better grip level, the more weight transfer. With more weight transfer to the front we need to adjust the brake balance more to the front. In some corners you need maximum stability during braking so you probably turn bias forward. In some corners you're braking and turning simultaneously and some of the traction budget of the front wheels is needed for turning so bias need to be rearward. Some braking points will be downhill and then gravity will cause the weight balance will be transferred more to the front, uphill gives more weight on the rear tires. On cars with high aero load the grip level and weight transfer during braking will vary with speed. The higher the speed the more grip, thus more weight transfer and more front brake balance. NOTE: If you are not exceeding the traction budget of a tire, you usually don't need to adjust the brake balance. For example, at high speed the extra load on tires caused by aero downforce will keep the wheels rotating even with a non-optimal brake balance. Hence you should focus to optimize your brake balance for medium and slow speeds (or the corner giving you the most problem). In wet conditions grip levels can vary between every corner and brake bias adjustments can be very profitable. Even in dry races track grip will change with track temperature. Also note that as the race goes on dust, marbles, oil will make the surface grip change from lap to lap. All of these environmental properties will affect the amount of weight transfer and may force you to adjust the brake bias. In addition to mass and center of gravity changes caused by fuel load, and tire wear giving different tire grip we also have also can have different brake levels due to brake pad/disc wear. Different wear on front and rear tires/brakes will cause changes in weight transfer. Another thing that affects tire grip levels and brake performance is the temperature of tires and brakes. Long braking distances will generate a lot of heat in the brakes and the front may overheat and fade. This will result in less brake power in the front forcing further bias changes to the front to prevent rear lockup. While brake bias adjustment has been available since long before kinetic energy recovery systems were invented, brake balance indeed change a lot depending on the degree of brake harvesting used. Brake harvesting can more or less replace brakes discs all together turning a 60/40 brake balance without harvesting to 90/10 with. All of the above may be reasons for adjusting brake bias from corner to corner. However, in rFactor most of the time the difference in weight transfer in different corners are not enough to force brake bias changes more than a few times during a lap.
Thanks for the info Novis, it is appreciated. I will probably not take a lot of it to heart though, as I tend to make myself way too busy with the way I drive as it is so don't need more work per lap I will experiment with it though to see what effect it has on my lap times as well as my brake zones.
Great stuff thank you! I will begin testing & certainly try altering the BB if I'm struggling with tyre wear or a tricky corner
I think it might be more to do with tyre degradation. I remember schumacher negatively talking about the impact of the pirelli tyre wear to formula 1 and how it's holding drivers back from driving at their full potential and pace. This article also mentioned how schumacher wears his tyres out most of all the drivers from driving at the limit non stop. But kers is probably playing a roll too of course but it's not something that will stop you from driving at the cars limit lap after lap, unlike the wear rates of these tyres which means you must pace yourself more and play the long game.
I remember Schumacher changing brake balance like that a lot in Ferrari years also. So I don`t think its something specific to post 2009 cars. Its just his style. But KERS might contribute something to it, yes.
@Paul: The only telemetry comparison between Schumacher and other drivers that I've seen looked more like Schumacher was especially good at staying on the absolute limit when getting out of the corners. That and he was a rain wizard.
In short, a single brake balance setting is rarely (if ever) optimal for every braking point on the circuit. Sometimes you want front, more rear etc. depending on all different factors as mentioned above. Schumacher, from early in his career, realised he could make up some time by optimising braking zones by adjusting the brake bias specifically for various braking zones during a lap (within reason, you don't always have time to adjust for every zone of course!) It was genuinely surprising that many, if any, drivers adopted this 'optimisation'. Certainly since Schumi moved into MGP Rosberg has learnt from 'the master' and can be seen doing the same thing. A few other drivers along the years had also done it but Schumacher seems to be the most active and certainly was the first driver you'd see changing it a few times a lap (a long long time before KERS days).
OK but as jubuttib said this wont make you seconds faster, just marginal benefit, most important is always speed out of corners..
I try to give a few tips on how to start working on the brake balance as it may not be as trivial as it sounds. It would be easy if the brake balance setting was the only setting affecting the brake balance but as you know many settings overlap in a race car and several settings will in the end influence the brake balance. Stuff in setup to keep an eye on - Brake balance, your main brake balance control and inside the car your only way to fine tune the balance: It's usually better to run this closer to 50/50 than to an extreme as you want to keep the front brake temperature as close to the rear as possible. Uneven balance is ok as long as you do not run into fade or wear issues. - Brake pressure: If brake pressure isn't high enough you won't exceed tire budget during braking. Find a pressure level high enough that can cause tire lockup during braking but low enough so you're comfortable controlling the car using degressive braking. - Engine brake map: The engine will cause additional braking though the drive wheels whenever the throttle is lifted. The engine braking is free braking power and you want to use as much of the engine braking as possible as the car balance and tire budget allows. - Differential (coast): The more differential the harder time the drive wheels will have to lockup during braking. While it is easy to stiffen the diff to remove some wheel lockup this will also cause entry to mid-corner understeer. The goal is to have only enough lock to stabilize the car during braking but not so much to cause the car to understeer. - Suspension: With different suspension settings you can influence in almost every way the car handles but it's also probably the most difficult part of the setup to grasp. Its way beyond this little guide and you are encouraged to find a guide devoted only to how to setup the suspension. How to start - Map the brake bias controls. - Turn up brake cooling, duct to max. We don't want change in brake balance due to brake fade. - Turn down engine braking, braking map to max value. - Start out with default differential but remember you can use it to alter the balance later. If possible, an easy way to find a starting point is to run the car down a straight and jump hard on the brakes. Look at the replay and see which end that locks the tires first and tune the balance so front and rear lockup as simultaneous as possible. Adjust the brake pressure so this occurs at a relatively slow speed. Test Use the above as your starting point. Run laps adjusting brake balance as needed or experiment and see how the car will react upon changes. Only small changes are needed. When you found a drivable setup with lowest amount of engine braking, turn the brake map down one step and give the car a new run. With a rear wheel drive car you may now need to move the brake balance setting a notch forward to compensate on the extra braking power on the rear wheels from the engine. Once you found the balance with the new engine map settings turn it down another step and repeat. How low should you go with the engine brake map? - If the car starts to oversteer on releasing the brakes the engine is breaking the rear too much and you have gone too far (with a rear wheel drive car). - If the brake balance becomes to forward and the front heat up (and wears) to much relative the rear. This will complicate car control at the end of the race. Also don't forget that you can determine the amount of engine braking with driving style by changing gear downshift points. When you find a decent brake balance and engine brake map, try to turn up the brake pressure a little. Best braking performance is with the highest brake pressure possible that you still can control the car without wheel lockups. You may have to readjust brake balance and engine brake map. Experiment with different diff settings When you understand how the car change behavior with brake balance and engine brake map changes it's time to move on to the differential. Like with the engine map, any change to the diff will force you to move the brake balance (and the engine brake map) settings also. Try to find a combination so the car is as neutral through the entry of the corner as possible. Stiffen the diff may be a solution to regain control when ýou must move brake balance rearward due to brake fade or wear. Once you get the hang of it it's possible to skip steps and you know which setting to change to get the wanted result. And then you have the suspension settings...
It's an individual preference and how good you can feel the car. I do it every lap on some tracks, it depends on cars or corners. I don't know if great sim racers do it more often, however I can understand if some drivers never use it. I would say that brake balance adjustments are not done to gain laptime but instead to not risk losing time. It's not to get a performance advantage but to improve the controllability of the car. You just don't want to lockup wheels and momentarily lose the control of the car, and that can be the difference by just moving the bias 1%. The result can be nothing at all in time or race ending. KERS is always changing? What do you mean by that? As far as I can understand KERS should be very consistent in action. The amount of harvesting is dependent on setting and engine rev. If so it will just work as an engine with a bit more engine braking. That would probably give a driver who's active with the brake bias a greater advantage, not the other way around. If anyone has links to articles on why KERS should make braking harder please share...
