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Would that allow a car to be dragged round a corner if the inside wheels get more braking force than the outer? Means you areias reliant on downforce to get round.
McLaren ran Brake steer in 1997, which was banned. They had an extra brake pedal. It worked for them iirc.
I suppose you could have the car automatically change brake bias across an axle with steering and suspension input, say as it’s riding the curb.
Or to stop the front inside wheel locking in low speed corners as the car pitches to the outside and unweights the inside wheel.
I fail to see what benefit that would bring
If you could set up a system to brake either just on the right or left you could in theory use it to counteract understeer rather than load up the front wing. So run a shallower aero solution for more speed, use the brakes to give you back the advantage in the corner, use the throttle as per normal to stop the car from slowing down too much.
So driver adjusted same axle brake bias was banned possibly leaving open suspension/aero adjusted bias. I’d have thought steering adjusted came under driver input? Dunno, maybe as a wheel unweighted the valve adjusted. Although that sounds a bit like a very crude ABS.
edit:- that pendulum brake in the link is cool. Hadn’t heard of that.
If you could set up a system to brake either just on the right or left you could in theory use it to counteract understeer rather than load up the front wing.
But the restriction is on the same brake disk. What they seem to mean is that the inner and out brake pistons must be the same size.
the forces applied to the brake pads are the same magnitude and act as opposing pairs on a given brake disc
Explain to me how different sized brake pistons acting on the same disk will counter understeer.
Except the new part to the regulations says:
“Any system or mechanism which can produce systematically or intentionally, asymmetric braking torques for a given axle is forbidden.”
So potentially maybe a team had found a way to create asymmetric braking torques across an axle
Adjustable bias across the car has been forbidden since McLaren did it, it was claimed to be a form of four-wheel steering.
The critical thing here is that they are talking about differential forces acting on the same brake disk, i.e. one pad exerting more force than the opposing pad. I don't see what benefit that would have.
What they seem to mean is that the inner and out brake pistons must be the same size.
Not quite: it says they need to apply the same force. If you have a vanilla hydraulic system then that means different sized pistons, but it would be more interesting if you could deliver different pressure to each piston in response to steering angle.
I don’t know enough about the technical regs to know what would previously have been feasible, but if the calipers are appropriately positioned then you could generate moments around the steering axis by manipulating the relative forces at the piston.
At worst I guess it would help marginally with temperature management by backing off the force on one side of the disc if it became hotter than the other.
But I’m guessing it’s been used to allow the brakes to be dragged a little on turn-in, either to shorten the barking distance or to get sharper turn-in without having to use things like camber which would affect tyre management.
Isn’t turn-in one of the things Verstappen’s been struggling with in the last couple of races?
Isn’t turn-in one of the things Verstappen’s been struggling with in the last couple of races?
It's inherent in the new aero regs. The position of the venturi throat is prescribed so the aero balance of the car is constrained by that. They need to use the front and rear wings to adjust the aero balance, but the front wing has a ground effect and front downforce increases as the wing gets closer to the ground at high speed. So, at high speed the car oversteers and low speed it understeers, which makes them difficult to drive. Merc and McLaren seem to have found a solution (maybe flexi wings?), but Red Bull seem to have some fundamental problems with how the aero and suspension interact.
thols2
Full Member
Adjustable bias across the car has been forbidden since McLaren did it, it was claimed to be a form of four-wheel steering.The critical thing here is that they are talking about differential forces acting on the same brake disk, i.e. one pad exerting more force than the opposing pad. I don’t see what benefit that would have.
This clarification is quite specifically talking about "asymmetric braking torques for a given axle".
I couldn't be bothered to look up the tech regs again, but it could be that the Mclaren 'brake steer' rule wording is something like "equal braking pressure must be applied to each calliper for a given axle". Therefore a system which prevents one pad extending could legally be used. I.e. perhaps you could have equal pressure acting at the calliper, but only a single pad extends, therefore reduced braking force.
Clarifications aren't added for no reason, either a team has this and the FIA don't like it, or a team has an idea and wants to try it, or a team suspects somebody else has it.
Red Bull's unusual retirement with brake failure the other week is now also rather interesting...
I.e. perhaps you could have equal pressure acting at the calliper, but only a single pad extends, therefore reduced braking force.
Yep thats how I'm interpreting it. On the outside wheel if only one pad is acting on the brake disc therefor less brake force you get some sort of 4 wheel steer assistance.
Other thing I could think of is does a reduced or increased force on the brake disc effect the suspension movement? Could a reduced brake force on the outside wheel lead to the suspension compressing less? Or increased force on the inside cause the suspension to compress more? Both acting to keep the underbody of the car flatter meaning the floor works more efficiently?
This isn’t about a braking differential between the two sides of the car, though. (Which AFAIK has been illegal since McLaren’s brake steer system.) This is about a differential between the two pads either side of a single disc.
Re-reading the wording, though, I think my previous thoughts were misplaced in a couple of respects.
Doohan signed to Alpine according to mestmotor.se (not official yet though)
Some Italian magazine (autosprint?) claims Newey has signed for Aston Martin. Also claims Stroll is trying to sign Verstappen.
No logic to it, but there's no team I'd rather see fail than Aston...Lawrence Stroll and his son, and Alonso. Then replace Alonso with Max.....awful combination
Seen those rumours too - I can see Newey at Aston as he has links with them already. It’s a team he could mould too, unlike Ferrari who are well, Ferrari!
Max would surely laugh at them though! He’d wait at least for 2 years after Newey has been there.
Mercedes is the solid option for him from 2026. Red Bill seems toxic and their engine could be great or could be shite.
In more interesting news have you heard the one about Mazepin to Alpine!!! 🙂
Re the braking forces.
I've no idea if someone has already tried it or just a clarification, but in the age of KERS, not all braking forces are from the caliper.
I suspect you could have equal hydraulic pressure on L & R calipers, but the KERS regen biasing the overall braking force to one side.
F1 brains are better than mine, so I'm sure someone has already been trying KERS brake bias.
In more interesting news have you heard the one about Mazepin to Alpine!!! 🙂
I did see that...surely even Alpine aren't that desperate!
The extended rumour is that Flavio is putting a deal together to sell the team(or part of) to Hitech Racing - hence the new boss who has links to the Mazepin family.
It’s the sort of depraved deal Flavio excels at.
https://www.planetf1.com/news/nikita-mazepin-f1-return-alpine-hitech-merge-rumours
And F1 say Andretti would be bad for the sport!!!
Does Newey still like a say in driver selection? That certainly wouldn’t work out at AM with seat-for-life boy there
I’ve no idea if someone has already tried it or just a clarification, but in the age of KERS, not all braking forces are from the caliper.
I suspect you could have equal hydraulic pressure on L & R calipers, but the KERS regen biasing the overall braking force to one side.
I think it could be done through the differential. As I understand it, the cars use clutch packs to tune the diff - under power in a straight line, they want the diff fully locked but it needs to be unlocked to stop the car understeering in slow corners. I'm sure it would be possible to design a diff that allows the KERS braking to be adjusted side to side. Whether it would be legal is another question. It's such an obvious thing that it's guaranteed that every team will have looked at it and already be doing anything that they are legally allowed to do.
Does Newey still like a say in driver selection? That certainly wouldn’t work out at AM with seat-for-life boy there
I think Stroll is underrated by his critics. Yes, he's only in F1 because his dad is rich but he's a decent driver. Having him as a number 2 to a superstar teammate shouldn't be a problem for a designer who's happy having Perez as a teammate to Verstappen.
Gary Anderson has an article on F1 diffs.
https://www.the-race.com/formula-1/how-f1-differentials-work
Having him as a number 2 to a superstar teammate shouldn’t be a problem for a designer who’s happy having Perez as a teammate to Verstappen.
Big assumption that he is happy with Perez.
Agreed that Lance is fine for a mid-field team, that's why I only mentioned the apparent seat for life situation
Seems totally in line with F1 being hosted in countries being run as one party state-autocracies that need a bit of a sports wash.
https://www.planetf1.com/news/christian-horner-investigation-appeal-process-red-bull-statement
Red Bull uphold result of investigation into Horner
I'm shocked! shocked, I tell you
Not read it, but did they mention any findings about the Pope's religion or what bears get up to in the woods?
Doesn't matter, cos the way things are going, Horner will be there on his own soon.
…with Checo and Tsunoda as his drivers!!! 🙂
While were on the Red Bull subject Marko has basically said Lawson and Hadjar will have seats in F1 next season.
So who’s going where? I can see Lawson being dropped straight into Red Bull.
I think Danny Ric will be gone.
Tho there's a seat going at Audi...
Yep - I think Danny Ric will be gone too.
His career with a top team was effectively over when he ran scared of Max and left Red Bull the first time.
Bottas seems to be favourite now to stay with Audi. May as well have some continuity as they seem short of that!
A few pundits have been saying that Bottas would be a good number 2 for Red Bull. He's quick, and doesn't rock the boat.
I'd like to see him with a decent drive. Not sure RB would appreciate his videos tho
In case you were wondering where all those cool looking clips were from
Nah I reckon Bottas will end up at Audi....unless they go for Schumacher
There were some photos of him doing rounds earlier, he had a R8 with a little 77 on the side
Just watched a YT commenting on the brake regs. Apparently Red Bull had an inertia valve after the brake by wire circuit that then split the braking force left and right. Think of it as a T in the circuit.
There was a little ball in the T that could move left or right as the car went around corners (inertia operated, not powered) so as you turn left, the ball rolls right partially blocking the right part of the T and pushing more pressure to the left brake. **
This increase the braking on the inside wheel to reduce understeer, similar to the McClaren 3rd pedal back in the day. McClaren reckoned the 3rd pedal was worth up to 1/2 a second a lap.
This was picked up on, and Red Bull stopped using it, about the Chinese GP. Since then, the performance of their car seems to have dropped about 1/2 a second a lap.
**Possibly slightly more technical but this is the basic idea as I understand it
Fair play I was thinking it was suspension compressiing a brake line /valve or aero related.
so as you turn left, the ball rolls right partially blocking the right part of the T and pushing more pressure to the left brake.
For that to work, it would have to completely block the brake line, so you'd have normal pressure on one side and zero on the other. As long as the port was open even the tiniest bit, the pressure on each side would equalize. I'm sure it would be possible to make a system with two proportioning valves controlled by a weight so that would limit the pressure to one side, but that would be a much more complicated system than a simple ball blocking off one circuit and hence it would be much harder to disguise as a normal junction.
Surely that would be clearly against the existing rules, so disqualification, as opposed to clarification of the rules forcing them to remove it?
Surely that would be clearly against the existing rules, so disqualification, as opposed to clarification of the rules forcing them to remove it?
Yes, that's my take on it. None of the reputable publications have mentioned it, it's just an internet rumour as far as I can tell. It's quite possible that one of the teams asked if such a system would be allowed, hence the rule clarification, but the assumption that Red Bull must have been cheating because they fell back into the pack (after the other teams introduced upgrade packages) just seems to be fanboi speculation from the internet.
Lots of talk on Twitter from respected journo's about it...
https://twitter.com/peterdwindsor/status/1824198674336948377?s=12&t=EQoHg-RGok071Fjc15ZHKw
https://twitter.com/scarbstech/status/1824228759567814841?s=12&t=EQoHg-RGok071Fjc15ZHKw
Actually, having mulled it a bit, with 4-pot calipers (or 2-pistons per side), you could use this system on one set of pistons per side so the affected wheel would still get 50% of the braking force, assuming two identical sized pistons. By using different sized pistons in each caliper, you could vary the ratio as you wanted. It would be pretty obvious that you were up to something though because you would have two brake hoses to each caliper instead of one (or a very bulky caliper if it was integrated into the brake caliper) and no F1 team would add any extra weight unless it gave some sort of benefit.
Lots of talk on Twitter from respected journo’s about it…
Speculation on the internet, in other words.
Scarborough's diagram doesn't quite make sense to me. Contrary to what he says, it wouldn't just reduce the pressure on the outside wheel, it would reduce it to zero (a simple valve like that will be either on or off as far as pressure is concerned, it's the pressure that matters here, not the flow volume). However, for the valve to close, the car must be turning before the brakes are applied. If you apply the brakes in a straight line, both brakes will be applied and they will then stay applied even if you turn in with them applied because closing the valve won't release the pressure that is already applied to the pistons on that side. For it to work during turn-in, the driver would have to brake in a straight line then release the brakes and turn, then reapply the brakes while turning. Problem is, if a driver swerved to avoid a collision and then braked, they would only have the inside brakes operative
...it's always going to be speculation as the FIA seem incapable of open discussion anymore.
The carpet at FIA HQ must have a massive mound under it with the amount of dirt swept under it.
The ball would not necessarily need to either be open or fully blocking the junction exit. Imagine that the surface the ball seats against has small grooves so there is just a little space for the fluid to squeeze through.
[i]the assumption that Red Bull must have been cheating because they fell back into the pack (after the other teams introduced upgrade packages) just seems to be fanboi speculation[/i] - It was immediately after China that the Rebull performance dropped significantly. It 'could' be possible that every other teams upgrades yeilded pretty much the same improvement over Red Bull or it could be that Red Bull dropped back.
If you look at the results, especially Checo's before and after China, there is a big difference. The same for Max but it is masked a bit more by his extreme driving talent.
Location - SP - MV
Bahrain - 2nd - 1st
Saudi - 2nd - 1st
Austrailia - 5th - DNF
Japan - 2nd - 1st
China - 3rd - 1st
Miami - 4th - 2nd
Emilia - 8th - 1st
Monaco - DNF - 6th
Canada - DNF - 1st
Spain - 8th - 1st
Austria - 7th - 5th
Britain - 17th - 2nd
Hungary - 7th - 5th
Belgium - 7th - 4th
**EDIT *** After typing all that in, this came up on my YT feed -
Assuming the system applies more braking to the inside wheel if braking while cornering, you’d best only use the lightest of touches on the brakes or you will lock up the unweighted wheel - no?
So I would want a non-linear response to the brake pedal too, to minimise that. And the front brakes to engage before the rear in that pedal travel (which they may do anyway).
Have the Red Bulls been locking inside wheels more than other cars?
I'm struggling to envisage a system where a little ball reliably rolls side to side in an oil based system - especially when the cars barely roll through corners.
(Plus as soon as the brake pedal is pressed the system is much more pressurised)
But I'm obvs not an F1 engineer!
little ball reliably rolls side to side in an oil based system – especially when the cars barely roll through corners
I don't think it would be rolling because the car was leaning over, but because it wants to go straight on while the car is turning.
As someone else said, if you apply all/most/more of the braking force to the inside wheel it's far more likely to lock up as it unweights.
The ball would not necessarily need to either be open or fully blocking the junction exit. Imagine that the surface the ball seats against has small grooves so there is just a little space for the fluid to squeeze through.
If there's any space for fluid to flow, the pressure will equalize on both sides. Brake systems aren't intended to carry large flows, they just transfer pressure, which doesn't require any flow once the pistons have extended and compressed the pads against the rotor. The cross-sectional area of the port that the pressure is transferred through doesn't matter so the port has to be fully closed if you want a pressure differential from side to side. Partially closing it won't give a pressure differential.
As someone else said, if you apply all/most/more of the braking force to the inside wheel it’s far more likely to lock up as it unweights.
From what I remember about the McLaren system, the drivers would drag the brake on the inside wheel through the corner. It was intended to aid with cornering, not to slow the car. The inside brake disks would glow red hot, I think that's how the other teams figured out what was happening.
So, I think in this case, the driver would brake and turn into the corner normally with both wheels receiving equal braking force. Then the driver would lift off the brakes and the inertia valve would block off the pressure to the outside wheel, then the driver would drag the brakes through the corner and the asymmetric braking would help rotate the car.
What if it was in a slightly flexible line or orifice
So if the ball blocked a port, more pressure would be needed for fluid to overcome the resistance. If it was a flexible tube, there could be a larger outer tube to limit loss in braking power as the flexible tube expands during braking.
Ignore me the ball would get stuck
What if it was in a slightly flexible line or orifice
So if the ball blocked a port, more pressure would be needed for fluid to overcome the resistance. If it was a flexible tube, there could be a larger outer tube to limit loss in braking power as the flexible tube expands during braking.
If the port is open at all, the pressure on each side will equalize. If the brake hoses are too flexible, you'll get a mushy pedal feel. I can't imagine that teams would want spongy brakes.
It's interesting that it's all rumour and innuendo so far and no proper journalist is touching it. They must be digging and digging tho. Andrew Benson will be trying harder than anyone, he seems to really hate Horner ?
thols2 - I think what you are saying about pressure equalizing and limited flow makes sense but the drop in performance, number of rumours and the new regs seem to suggest that something was happening. I was basically quoting from the YT videos I have seen and the sources that they quote. Agreed that they are not hard evidence.
Article from Mark Hughes*...
...Red Bull talked of as main user, but also that McLaren and Mercedes could be using a similar system. We'll see how they all fare in twisty Zandvort! 🙂
*subs only but you can register to view.
*subs only but you can register to view.
Or just open in an incognito window in Chrome
If the port is open at all, the pressure on each side will equalize
The system would control a pressure regulating valve, not a flow regulating valve, so the brakes can be biased as needed to aid the steering of the car
The system would control a pressure regulating valve, not a flow regulating valve,
The diagram that Craig Scarborough had was of a flow regulating valve closed by inertia.
That Mark Hughes article references braking the outside wheel more, which makes more sense
[i]That Mark Hughes article references braking the outside wheel more, which makes more sense[/i]
Possibly, but something that moves by interia - the car entering a corner - can be made to act on either side depending on your design I guess.
I understand the outside wheel would be more loaded so could take more braking but wouldn't that pull the car on a wider line rather than tighter, thus increasing understeer?
I am guessing but I would have thought that you wanted the inside wheels braking more than the outside and then use the driver to control the lock up point.
He talks about it being a handbrake turn effect....dunno, don't really understand it.
Good job I'm not an engineer in F1 really.
The original McLaren system braked the inside rear wheel. Drivers apparently had to learn to stay on the throttle slightly to avoid locking the inside wheel. The outside wheel being driven would also tend to turn the car into the corner.
The diagram that Craig Scarborough had was of a flow regulating valve closed by inertia.
It’s just a simplified diagram. A proper hydraulics diagram wouldn’t make sense to most readers
It’s just a simplified diagram.
It's not simplified, it's a diagram of a flow regulating valve turned on or off by lateral acceleration. When the car is cornering hard enough to close the valve, the outside brake is disabled and the driver can feather the brake to help rotate the car. The brakes will work symmetrically under straight line braking, then the driver needs to lift off the pedal as he turns in to release the outside brake, then feather the brakes to use the inside brake to help turn the car.
This all sounds a bit odd.
I don’t follow the Scarbs diagram either: my interpretation is as per hols2’s, ie that it has either no effect on pressure and/or will completely freeze one caliper at some point.
I also don’t follow Mark Hughes’ thoughts. I don’t see how a “handbrake turn effect” is relevant: the handbrake turn works by locking the rear wheels so that they have a lot less retardation than the front wheels. Until the wheels lock, there is no handbrake turn as such, it’s effectively just a bit more rear brake balance. And he talks about how applying more braking to the outer rear wheel induces a turning effect into the corner—that makes no sense either: the opposite is true.
What’s more, the regulations as I read them relate to asymmetric forces at a single caliper. Maybe I read them wrongly. But the regulation relates to “a given brake disc” and “a given axle”. There is no single rear (or front) axle, there is one per wheel. So I don’t get why all these rumours seem to relate to differential forces between the two wheels. I’ve always interpreted it as relating to differential forces across two sides of a single disc.
Edit: looking through the regulations, they use “axle” both to refer to the four physical axles at each wheel and to the two virtual axles front and rear. Quite why they’ve made that term ambiguous is a bit baffling, but I guess it makes a nice loophole to work with if you’re confident you can argue it in court if needed,
Gary Anderson has an article that explains one way an inertia valve could help by causing the inside rear brake to drag through corners. The brakes would all receive full pressure when braking in a straight line, but turning would activate the inertia valve which would prevent the inside rear brake from releasing. The driver would have to keep some pressure on the brake pedal as he turned in, then would release the pedal. As long as the car was turning above a preset g-level, the inside rear brake would keep dragging. The amount of braking could be adjusted by changing the weight and/or spring. Once the car stopped turning, the valve would open and the brake would stop dragging.
Important point is that the changed wording was apparently copied from the new 2026 regs, so there's no evidence that it was done in response to finding that anyone was actually using asymmetric braking, they may be just closing off a loophole before anyone tries it.
https://www.the-race.com/formula-1/f1-intriguing-new-brake-rule-tweak-gary-anderson/
The interesting thing about that sort of device is that if it were to stick, it would cause exactly the issue that Verstappen had in Australia. Obviously, it’s not the only thing that could cause it, but Brembo (whose discs and calipers are used by the entire grid IIRC) publicly stated it wasn’t an issue with their components and there was no hint that it was something simple like debris caught under a pad. Red Bull never revealed what the cause was. Besides, when was the last time a single F1 caliper locked on like that? Not sure I’ve ever even seen it. For sure, you’d be jumping to conclusions to think case closed, but a passively-controlled valve failing to disengage seems to be one very plausible explanation.
If I were designing it I would design it to leak slightly so that the pressure equalised slowly. That would give a larger effect on turn in but lessening through the corner and minimising the chances of it locking a brake on.
It would also operate on the rear inside wheel, both allowing the front to track nicely, and to allow throttle balance of the effect.
As you straightened and accelerated the effect would tail off beautifully.
It might however lead to slightly different cornering lines. Anyone noticed anything odd about RB or MV cornering lines? In particular do MV and SP have different cornering styles that might make this work for one and not the other?
If I were designing it I would design it to leak slightly so that the pressure equalised slowly.
Yes, Gary Anderson says they did something similar back at Jordan, where they could tune the brake release for different wheels. Given the engineering resources the teams have, I'm sure they would figure out clever ways to optimize the system beyond being an on-off switch.
it would cause exactly the issue that Verstappen had in Australia.
Or Piastri at Hungary in a long fast corner when all of sudden he decided that he couldn't brake, and allowed Norris to gain 3 seconds on him, and all the farrago that followed. In his radio transmission he said basically, "yeah it's OK, I know what I did wrong" which some folks have translated as Piastri getting the brake setting wrong and not wanting to publicly broadcast that he'd done so.
If it was just a rule change why is there such a song and dance being made about it? Rule clarifications must happen all the time with no one batting an eyelid.
This weekend will be revealing though - it's the sort of system that could work a treat around Zandvoort.
Motorsport.com are saying that an FIA spokesperson told them nobody was using such a system.
Could just be that a team wanted to use it and asked for clarification.
Yes, replicating the McLaren brake steer functionality without checking that it was legal first would be pretty dumb, especially for Red Bull who had an utterly dominant car last year.