brakes wrong simulation

[tseklias]

This problem i witnessed a long time ago i've discussed it here but noone else seems to be bothered so much by this bug so i decided i open up a topic so all can easily see it and tell their opinions about.

What i have tested is:
1.Go on any track and GRADUALLY press the front brake up to 100% at any speed the wheel just wont lock(i even tried it on a 100% wet track the front wheel just don't want to lock!)
2.Same goes with the rear brake(only this time a button assigned and not an axis) the wheel won't lock
3.I've tried the first step on a gravel part of a track the wheel finally locked, locked but the rider stayed onward and kept going for like 20m with the front wheel locked!
4.Same as the above i've tried the second step(rear brake) on the gravel the wheel locked like 2-3 meters from when i pressed it.

Now this i have discussed with Max but he states(correct me if i lie) that GpBikes at this current state behave right. Well i thing that Max is plain wrong on this matter. Don't get me wrong i appreciate Max and think that he's knowledge exceeds by far mine and propably the rests' of us here-so pls don't move offtopic .
Since right now i can't make a video myself showing that, i asked 5 different quys over youtube that make videos(chosen based on who i think seems to have more experience) to make one video locking instantly the rear wheel(WITHOUT pressing the front brake, move up on the handlebars or anything you thing might take off weight from the rear) for a fraction of a second just to show that it is possible and not putting them in danger.
Two of them told me that will make this video at some point so i'm still waiting...BUT all 5 admitted(and i can post their replies for the incredulous) that the wheel will lock-INSTANTLY!

Now my opinion on this matter is that, even if you carry this chick no matter the speed you have(same applies if you run with 300kmh as 10kmh) if you jump on the rear brake the wheel will lock. Imagine not pressing the brake with your toes but litteraly kicking the pedal with your heel.
Same goes for the front brake even if you press gradually the brake you will never be able to fully press the brake(100%) cause the front wheel will lock or even worse you'll start an endo and end up with the motorcycle on your back.
Also i believe that when your speed is high let's say 200kmh and you quickly press the front brake to 10%(not that i think it can be measured with a percentage but for the sake of the example) the motorcycle will start to lower speed. Now if you press the brake again at 10% but only this time with 20kmh the wheel will lock!

I understand that temperatures raises on the discs under braking and you SHOULD gradually need to press it more and more as your brakes will start to faint, so this is beautifully simulated in GpBikes. But the only thing is that this must be applied on half the distance we now press on our controllers, meaning you MUST NOT have the ability to reach 100% of the brakes, gradually or not, while running the wheel MUST BE LOCKED.

I also understand the physics behind weight, speed and all these things Max explained but i insist that you can lock both front and rear wheels even if you're running on glasspaper with the chick above no matter the speed!
Also please don't get into the discussion that if this changes then our controllers will be too sensitive under braking cause this is a simulation and must remain a simulation no matter what.
BobPP stated ''...i think we have reached the point our controllers become useless...'' talking about an xbox controller propably and not an IAS system style controller or any other where you have actually the ability to simulate brakes.
Even if this is right(which i personally believe it is) the further develop of GpBikes should not be based upon an xbox controller but as in reality!
After all if someone finds the brakes too sensitive he has the ability to change the force applied from the ''inputs'' tab under settings.

[Hawk]

Hi tseklias.

Hmmm... This is interesting, as I'm sure I can lock-up my rear brake quite easily, and also end-over the bike with my front brake if I brake too hard(I don't think the front brake does lock-up in real life unless your speed is very low or your healed over(very complicated and different forces acting on the tyre grip depending on your bikes attitude, speed and weight) when braking hard. Hence you get front end washing away if your braking too hard whilst leaning into a corner.

Are you sure you have your brake controller settings correct?

I could be wrong(long time since I used my rear brakes. Lol)..... Anyway. I'll do some tests and see what happens on front and rear brakes for me and report back here. 

Hawk.

[tseklias]

Hi tseklias.

Hmmm... This is interesting, as I'm sure I can lock-up my rear brake quite easily, and also end-over the bike with my front brake if I brake too hard(I don't think the front brake does lock-up in real life unless your speed is very low or your healed over(very complicated and different forces acting on the tyre grip depending on your bikes attitude, speed and weight) when braking hard. Hence you get front end washing away if your braking too hard whilst leaning into a corner.

Are you sure you have your brake controller settings correct?

I could be wrong(long time since I used my rear brakes. Lol)..... Anyway. I'll do some tests and see what happens on front and rear brakes for me and report back here. 

Hawk.

No my controller is pretty right. I've tested at like 3-4 PCs so far with 3 different controllers(2 xbox360 & a ps3). Just give it a try Hawk go at any track and on the straight press only the rear brake not the front(so weight doesn't move up forward) the wheel won't lock-hell it doesn't even lock under 100% wet track and i also played with the gain input from the settings.

But the problem is not only that it doesn't lock it's the general feeling the brakes gives you that they are WAY too weak.

As to if a motorcycle can actually lock the wheels under braking just think of it like that:
Motorcycles comparing to cars have much less contact patch and less weight right? Except the thing that cars have this thing(i don't know how it's called) that multiplies your pressure, yet cars can EASILY lock the front wheels. We agree so far? If we agree then there's nothing else to discuss cause just this example shows that you can lock the wheels on a motorcycle FAR EASY!
Now if we don't agree, you know cars have also handbrakes where no multiplier interferes. You can or not lock the rear wheels of a car with your handbrake? Yes you can! And still keep in mind the contact patch and the weight of the car PLUS the tiny discs!

You think motorcycle companies will equip you with a braking system that doesn't have the power to stop itself??!?!!?!!?
Even the old style brakes(i don't know the name from this one also) before moving up into discs have the ability to lock the wheel OF COURSE with more pressure than discs but it has the power to lock the wheel.
I don't know how you end up with this conclusion that motorcycles don't have the power to lock their wheels but it is plain wrong.
Haven't you ever seen those races where 10 riders try to line up before entering a tight corner and one falls under breaking(where the front wheel locks and the motorcycle's drops right or left and they kiss the ground) then usually a pile up follows.

[Napalm Nick]

I think I'm right saying a front wheel will only lock if the brake is squeezed very hard and fast ie: before the bike weight has been transferred fully forwards and therefore before grip has increased to compensate;  or when the front suspension has compressed to its stops, or if too much brake is applied at slow speed when more often a stoppy occurs due to the transfer of weight forwards being too quick.

A rear brake should lock easily once a front brake is applied because all the weight of the rear is transferring to the front - no weight = no grip.

Hence why the best way for a biker to brake is rear first followed by front and release of rear then releasing front smoothly as the bike slows - weight moving backwards, grip decreasing, risk of lock-up increasing.

So, in summary the front brake should lock if squeezed to the Max immediately / if the forks bottom out/ or if too much brake is applied at slow speed. The rear brake will probably not lock on initial application but as a deceleration starts occurring and the weight moves forward the risk of locking hugely increases.

I will have a play on GpB later I'm sure there will be another factor such as the bike being used?

[Napalm Nick]

   Right then I've been out testing and these are my results. I record what I expected to see and whether or not it did occur based on my previous post.
    I tested on both a Moto3 and the Aprilia RSV4 both having the same results.
    Only assists on were Rider lean and Auto Clutch (I knew id be stalling a lot)
    No control Smoothing, Linearity 100% and Gain 100%
    I'm not rigged up to record the video but I analysed brake/wheel timing and reaction using the Orbit mode in replay at 1/5th speed in each case.

-Rear Brake Only full on at 60MPH TARMAC  - no lock -(Not Expected  should be no lock followed by a lock as weight transfers forward during deceleration) like below
-Rear Brake First then Application of Front Brake as well - no rear lock at first, rear lock as front applied (Expected)
-Rear Brake Only full on at 60MPH GRASS - Lock after 2 metres (Totally Expected - Low grip getting lower as weight transfers forward on deceleration).

-Front Brake Only Quickly Full on at 60MPH TARMAC - no lock but stoppie (Not Expected would of liked a quick lock up before the stoppie threw me 30 ft down road))
- Front Brake on Hard at 60MPH not reducing strength as bike slows - no lock (Not Expected would of expected a lock near to stopping speed)
-Front Brake on Hard on GRASS - front lock up - Expected  but the bike is too stable I could even steer with front locked up.

-Untested - Braking with forks bottomed out - couldn't reproduce.
-Untested - Does Auto clutch disengage the engine at low speed which would affect braking? hmmm I doubt it.
-Untested - changes in Linearity and Gain - think you already tested these?

Conclusion - better braking physics than I anticipated. Like everything in life there's room for improvement, and, of course this is based on my knowledge of braking physics which, also like everything, is debate-able.

I hope this helps you out with testing your observations a bit  tseklias.

Nick.

[HornetMaX]

Others have already reported that the front brake in GPB seems to be kind of more tolerant now than what it was before. Not going to double check this, but out of memory I can agree with that.

Also i believe that when your speed is high let's say 200kmh and you quickly press the front brake to 10%(not that i think it can be measured with a percentage but for the sake of the example) the motorcycle will start to lower speed. Now if you press the brake again at 10% but only this time with 20kmh the wheel will lock!

Just to be sure I understand you correctly, why do you think the same breaking force (10%) has a different effect at 200Kmh and at 20Kmh ?

I understand that temperatures raises on the discs under braking and you SHOULD gradually need to press it more and more as your brakes will start to faint, so this is beautifully simulated in GpBikes.

Actually this is not simulated at all in GPB, as far as I know.

As to if a motorcycle can actually lock the wheels under braking just think of it like that:
Motorcycles comparing to cars have much less contact patch and less weight right? Except the thing that cars have this thing(i don't know how it's called) that multiplies your pressure, yet cars can EASILY lock the front wheels. We agree so far? If we agree then there's nothing else to discuss cause just this example shows that you can lock the wheels on a motorcycle FAR EASY!

The logic above is totally flawed, it does not show/proof what you are saying it is.

Now if we don't agree, you know cars have also handbrakes where no multiplier interferes. You can or not lock the rear wheels of a car with your handbrake? Yes you can! And still keep in mind the contact patch and the weight of the car PLUS the tiny discs!

Tiny discs ?!

    I'm not rigged up to record the video but I analysed brake/wheel timing and reaction using the Orbit mode in replay at 1/5th speed in each case.

You may want to to have a look at that: http://forum.piboso.com/index.php?topic=1151.0
Wheelspeed (f and r) is available in the telemetry.

MaX.

[Napalm Nick]

Thanks for the link Max that looks an excellent tool.

[tseklias]

Others have already reported that the front brake in GPB seems to be kind of more tolerant now than what it was before. Not going to double check this, but out of memory I can agree with that.

I have witnessed that... so if the brakes were ok in the first place like you admitted at our first conversation why did piboso make a change on that?

Just to be sure I understand you correctly, why do you think the same breaking force (10%) has a different effect at 200Kmh and at 20Kmh ?

I told you i'm not a physician expert so an approach to try to explain it will make me sound stupid instead of giving you the image. Yet does this happen or not? My belief is that it happens out of experience i know i'm right.

Actually this is not simulated at all in GPB, as far as I know.

Well if this is not simulated can you please tell me why can i reach 100% of the front brake pressing it GRADUALLY without locking the front wheel? Why does this happen why?

The logic above is totally flawed, it does not show/proof what you are saying it is.

Not at all! I think calling it a flaw without stating why is not a try to explain it, it's a try to cancel me... but anyway

Opel astra opc 2013m: 2x355 discs pressed by 4 piston calipers 245 tires
Suzuki gsxr 600 04m: 2x300 discs pressed by 4 piston calipers(we don't know the contact patch of this)

So here's why compared to a car(710 total diameter of discs) a motorcycle(600 total) has huge brakes. Now the car is not a racing machine(at least not the example i brought), you're supposed to put all your family in(supposing you're 5 members total) raise the car's weight by a lot and still the car will lock the wheel under any circumstances easily! Now in this example if you think that the gsxr(and i chose an 600cc not a 1000cc to be more comparable) can't lock it's wheels well then what else can i say to give you an image, i don't know.

Tiny discs ?!

Well yeah compared to a bike yes the car has tiny discs at the back, like it does to the front. Yet once more despite this difference the car has the ability to lock it's wheels. If it didn't then there wasn't a reason to invent ABS. Think about it like that.

I don't know how else to state it to show you that the brakes system and how they function now in Gp needs massive changes. If a whole community of motorcycle simulators members does believe that motorcycles doesn't have the power to lock it's wheel well then i can't say anything more cause i think it will become gaza strip here. I don't know maybe the whole matter needs to be posted at a REAL RIDERS forum.

One more thing Max, if you think that Gp at the current state doesn't need changes why don't you go outside showing us how you can reach gradually 100% of your front brakes and not lock the wheel aswell as how can you heelkick the rear brake and not lock the wheel also? Im just desperate and mad(angry) to show you you're wrong on this matter so for the love of god don't do it!!!

[HornetMaX]

Others have already reported that the front brake in GPB seems to be kind of more tolerant now than what it was before. Not going to double check this, but out of memory I can agree with that.

I have witnessed that... so if the brakes were ok in the first place like you admitted at our first conversation why did piboso make a change on that?

Your initial message (a while ago) dealt only with rear brake locking. You stated it should always happen, instantly. It's wrong.

The logic above is totally flawed, it does not show/proof what you are saying it is.

Not at all! I think calling it a flaw without stating why is not a try to explain it, it's a try to cancel me... but anyway

You're trying to prove something via a logical deduction by analogy between two totally different cases, cars and bikes. See below.

Opel astra opc 2013m: 2x355 discs pressed by 4 piston calipers 245 tires
Suzuki gsxr 600 04m: 2x300 discs pressed by 4 piston calipers(we don't know the contact patch of this)

So here's why compared to a car(710 total diameter of discs) a motorcycle(600 total) has huge brakes. Now the car is not a racing machine(at least not the example i brought), you're supposed to put all your family in(supposing you're 5 members total) raise the car's weight by a lot and still the car will lock the wheel under any circumstances easily! Now in this example if you think that the gsxr(and i chose an 600cc not a 1000cc to be more comparable) can't lock it's wheels well then what else can i say to give you an image, i don't know.

Tiny discs ?!

Well yeah compared to a bike yes the car has tiny discs at the back, like it does to the front. Yet once more despite this difference the car has the ability to lock it's wheels. If it didn't then there wasn't a reason to invent ABS. Think about it like that.

You're assuming the power of a braking system depends on the disc diameters (and only on it). If you compare two bikes, using the disc diameter to compare can be roughly true (assuming everything else is similar), but comparing a bike and a car, this is totally not true. Way too different. Pads characteristics, pads surface, disk thickness and mass and, of course, tire characteristics, CoG position are all factors that make your comparison (and your deduction) irrelevant.

BTW, in your example the car has 355mm discs, the bike 200mm discs and you say the car has tiny discs. I'm lost ...

I don't know how else to state it to show you that the brakes system and how they function now in Gp needs massive changes. If a whole community of motorcycle simulators members does believe that motorcycles doesn't have the power to lock it's wheel well then i can't say anything more cause i think it will become gaza strip here. I don't know maybe the whole matter needs to be posted at a REAL RIDERS forum.

We have some here (and some of them have a good understanding of why a bike does what it does).

One more thing Max, if you think that Gp at the current state doesn't need changes why don't you go outside showing us how you can reach gradually 100% of your front brakes and not lock the wheel aswell as how can you heelkick the rear brake and not lock the wheel also?

I asked the same to you for the rear brake a long ago and haven't seen anything coming ... not that it would prove much though: I don't have a motogp rear tyre.

Can a bike lock the rear or the front ? Yes of course, in some situations (otherwise we wouldn't have ABS systems for bikes).

Does it happen instantly ? No, never.

Does it happen in GPB ? Under some circumstances yes (both rear and front).

Should it happen more (or more easily) ? I don't know, I'm open to riders' feedback on this.

You seem to think that a good braking system must allow you to lock the front. The part in quotes below is taken from the book "MotoGp Technology" (N.Spalding, second edition, pages 249-250):

"... These brakes are very powerful, and it is no longer the size of the brake, or the amount of braking that is available, that is the limiting factor on a racing motorcycle. Front tyre grip is now so good that, with the height of the center of gravity and the quality of the front tyre and suspension, with most brakes it is possible to flip the bike over in a giant stoppie if too much brake is applied."

[read this carefully]
"In MotoGP, the work of the brakes has increased as the tyres have evolved. It used to be that the tyre grip was the limiting factor, but now tyres have developed so much that the only way to achieve maximum braking is to slam the brakes on hard in order to squash the tyre hard against the track, effectively increasing the the are in contact with the track and, in turn, increasing the amount of stopping force that can be applied. This strategy has been so successful that the limiting factor now is a motorcycle's propensity to trip over the front tyre, and flip over, if the brakes are applied too savagely."

In case it's too hard to understand, it says that (at least on top end racing bikes), you don't lock the front that easily because most of the time, before being able to lock, your bike will be flipping over.

Designing a braking system that can provide more braking force than what the tyres can handle (on straight and under load) is always bad because that extra braking force can never be used.
That's why they don't do that: they design to get the max breaking power the bike+tyre can handle, then they try to minimize the mass (which is rotating and unsprung, so a gain there is very important).

MaX.

[tseklias]

You're assuming the power of a braking system depends on the disc diameters (and only on it). If you compare two bikes, using the disc diameter to compare can be roughly true (assuming everything else is similar), but comparing a bike and a car, this is totally not true. Way too different. Pads characteristics, pads surface, disk thickness and mass and, of course, tire characteristics, CoG position are all factors that make your comparison (and your deduction) irrelevant.

BTW, in your example the car has 355mm discs, the bike 200mm discs and you say the car has tiny discs. I'm lost ...

No the motorcycle has a total of 300x2 discs for a very small contact patch the car has 355x2 discs for a 245x2 total tire patch. So the car comparing to the car has tiny discs.

I asked the same to you for the rear brake a long ago and haven't seen anything coming ... not that it would prove much though: I don't have a motogp rear tyre.

Can a bike lock the rear or the front ? Yes of course, in some situations (otherwise we wouldn't have ABS systems for bikes).

Does it happen instantly ? No, never.

Does it happen in GPB ? Under some circumstances yes (both rear and front).

Should it happen more (or more easily) ? I don't know, I'm open to riders' feedback on this.

You seem to think that a good braking system must allow you to lock the front. The part in quotes below is taken from the book "MotoGp Technology" (N.Spalding, second edition, pages 249-250):

"... These brakes are very powerful, and it is no longer the size of the brake, or the amount of braking that is available, that is the limiting factor on a racing motorcycle. Front tyre grip is now so good that, with the height of the center of gravity and the quality of the front tyre and suspension, with most brakes it is possible to flip the bike over in a giant stoppie if too much brake is applied."

[read this carefully]
"In MotoGP, the work of the brakes has increased as the tyres have evolved. It used to be that the tyre grip was the limiting factor, but now tyres have developed so much that the only way to achieve maximum braking is to slam the brakes on hard in order to squash the tyre hard against the track, effectively increasing the the are in contact with the track and, in turn, increasing the amount of stopping force that can be applied. This strategy has been so successful that the limiting factor now is a motorcycle's propensity to trip over the front tyre, and flip over, if the brakes are applied too savagely."

In case it's too hard to understand, it says that (at least on top end racing bikes), you don't lock the front that easily because most of the time, before being able to lock, your bike will be flipping over.

Designing a braking system that can provide more braking force than what the tyres can handle (on straight and under load) is always bad because that extra braking force can never be used.
That's why they don't do that: they design to get the max breaking power the bike+tyre can handle, then they try to minimize the mass (which is rotating and unsprung, so a gain there is very important).

Yeah i read Max, yet i don't see somewhere written that it can't lock the wheel. I really doubt that if for example you run with 300kmh and you jump on the front brake you're gonna flip over. The front wheel will lock in the example above. If you run with lower speed then yes it is most likely that the motorcycle will flip over. You also said before that the shifting time mustn't be faster cause Gp doesn't currently simulate modern MotoGP physics. Yet the ability of a huge tire grip that will flip the bike over is simulated(modern). Yes, no, i like, i don't like... decide!

Also i don't have a problem with flip overs, my problem is that if YOU GRADUALLY PRESS THE FRONT BRAKE YOU CAN REACH 100% AND THE BIKE WON'T FLIP OVER OR LOCK THE WHEEL. I can't make it more clear please read carefully. If also you run into grass the WHEEL LOCKS AND THE RIDERS KEEPS GOING TILL THE BIKE STOP. THIS IS TOTALLY FAKE! No man in the world can lock the front wheel and go for let's say 20m and stay on the bike! I currently haven't witnessed any front lock in Gpb as you say, so if you ever did please say it or better post a video here. Meaning the bike is standing upright(vertical).

Well if it was so easy for me to make the video i would have not asked random guys on youtube to help me with that neither i would write down lines and lines here. The story of my life?! I don't think so...
Yet BE SURE that when i have this chance i will make the video.

[HornetMaX]

As you want man, I tried. Good luck.

MaX.

[BOBR6 84]

At very high speed you brake as hard as possible  Initially!, You dont apply more brake as you get closer to the corner. The tyre loves hard braking. It Does not lock up..

Maybe when they tried anti-dive forks the front could lock up..? They scrapped that idea for a reason tho..

Personally I think the brakes in GPB are excellent! Sure, slightly more forgiving than previous beta's but probably down to more feel..

I raced today  I was abusing the front brake right into the corner.. As long as you dont suddenly apply more brake, you can get away with braking with good lean angle too.. Bike tyres are amazing 

[BOBR6 84]

Look at pedrosa's endo at motegi  he braked hard enough with carbon brakes for the rear to lift.. Rear lift will always happen before locking up.. Thats why they dont lock up 

[Daniel_F]

that would defend on the bike configuration i guess.. in my bike (cbr 600 f 2001) the wheel blocks even b4 bike thinking of lifting rear wheel...

anyway i think any bike with cold tyres and without abs would lock b4 lift the rear

[BOBR6 84]

So are you saying your front wheel/tyre locks up and skids when braking on your bike??