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Thanks!

After few days of troubleshooting bit by bit I finally nailed it.

The issue was with the output structure being 4 bytes shorter (from m_iVersion till m_sData part) than the structure you posted. Can't say what's exactly missing in the game output but that's it. It's weird if it works for you at the same time but that's what I get from my GP Bikes.
I removed "int m_iSplit;" (just random value) and it works well now. I especially compared several times to your code, but yep, no other difference.

Thanks Max, I appreciate it!
I just have a feeling something obvious is missed so maybe second look can help. Insterestingly though, state parameter of the structure is read well, problem is just with telemetry data.
I can post a code but there's just copy paste from Piboso's and your code from the first page.

Hi,

I don't have the time to look into this, hence just speculating: looks like garbage, so potentially data structure misalignment.
Have you compiled your app as x64 ?

Just tried x64, no change.
Ye, apparently something with data structure but I've just copy pasted structure code posted by Piboso so no idea really where mistake can be.

Hey guys, can you please help me out?
Sorry for possibly a noob question but I'm tad confused. I'm using Max's test code from the first page and getting the data, but it's in some strange format like this when starting the bike:

''Speed940.48Kmh
Revs1117953633Rpm
State: 2
Speed938.721Kmh
Revs1117925790Rpm
State: 2
Speed936.422Kmh
Revs1117905668Rpm
State: 1""

So data isn't too realistic.

So what am I doing wrong here, is the data in some specific format?

Interestingely enough, I can see the reply but it's empty i.e. I see black screen when clicking to some bike attached cameras. But prolly I just don't have this bike. I think fraps + youtube is the best idea here. 

You should notice that I'm talking about "peak slip angle" and "maximum performance out of the tyre". I'm not talking about any possible slip, that's obvious.. Type of physics that I'm trying to discuss here is "racing-wise" not just "any slip of anything anywhere".

So you mean that with a rigid tyre the peak slip angle is zero ?

No I mean that:

peak slip angle would tend to 0 while stiffness of the wheel tends to infinity (if we take regular rubber static/slipping frinction values).

no more no less. It's tending to 0 only with regular rubber friction coeffs but not necessarily for others materials.

Or maybe by "peak slip angle" you mean "the smallest slip angle at which the tyre generates the maximum force over all possible slip angles" ?
Which would be a pretty unusual definition of "peak" ...

No I meant "slip angle when tyre generates max lat force".

Because you told Hawk he was correct before adding something that, in facts, says he was wrong (thing on which I agree).

Maan.. ye, lets just finish it.

Slipping as "slipping friction" - no, it's a physical process when friction surfaces are moving in relation to each other while in contact.
Slipping of the tyre - as a physical phenomena when rotation direction of the tire (not a deam vector , but where the wheel is "pointed") is not matching direction of its headway motion - yes, I can say that it's caused by tire flex, cause otherwise peak slip angle would tend to 0 while stiffness of the wheel tends to infinity (if we take regular rubber static/slipping frinction values).
So if it weren't for tyre flex - there would be effectively no slip angle while going around the track fast "i.e. having maximum out of the tyre".

I disagree. Slipping, longitudinally or laterally, does not happen because of tyre flex. You can slip with a perfectly rigid "tyre".

You should notice that I'm talking about "peak slip angle" and "maximum performance out of the tyre". I'm not talking about any possible slip, that's obvious.. Type of physics that I'm trying to discuss here is "racing-wise" not just "any slip of anything anywhere".

Correct. To be exact: it's always slipping while producing force, not just in motion.

So in fact it's not correct: it's slipping if it is generating force. Ideally it could be in motion (constant speed and direction) without any slip.

You said incorrect and just repeated what I wrote.

P.S. Anyhow, I long lost the taste for fights over physics, that's what I've been doing for years in the past so if you want recognition - I subscribe to your latest explanations about tyre dynamics. They are accurate.

What I'm really interested here - is only fixing the issue in the game that's obvious to all of us.

I wonder if this discussion would interest Piboso?

I hope so. Not the whole discussion but at least the bug we are talking about. Vehicle behaviour is imho the most important thing for a simulator so I guess a lot of people would appreciate that fix (eventhough they might not realize what's exactly the problem while playing GP Bikes, but they should definitely feel the improvement).

But ... slipping happens because of tyre flex  ?!

Slipping as "slipping friction" - no, it's a physical process when friction surfaces are moving in relation to each other while in contact.
Slipping of the tyre - as a physical phenomena when rotation direction of the tire (not a deam vector , but where the wheel is "pointed") is not matching direction of its headway motion - yes, I can say that it's caused by tire flex, cause otherwise peak slip angle would tend to 0 while stiffness of the wheel tends to infinity (if we take regular rubber static/slipping frinction values).
So if it weren't for tyre flex - there would be effectively no slip angle while going around the track fast "i.e. having maximum out of the tyre".

As I understand the theory, a tyre is slipping all the time it's in motion, whether under acceleration or not?

Hawk.

Correct. To be exact: it's always slipping while producing force, not just in motion.

You're gonna make somebody angry with that
Of course real slipping happens in the game engine: when they tyre diagram (force vs long slip or lat slip) crosses the origin, that means that if the tyre is not slipping it is not generating any force.
As in GPB you're able to take turns and to accelerate from stop, slipping is happening

Thanks cap, I agree 

Also, what my tool show are the diagrams in pure longitudinal (i.e. no side slip) and pure lateral (i.e. no longitudinal slip). In real conditions you normally have both at the same time (and the maximum force is somehow shared between the two components).

I double that.

with "slip angles being defined by the tyre spec": the tyre model does not define a "slip angle".

well, it does in a way. Of course in collaboration with other factors i.e. what the bike is doing on the road etc but lets not argue over nothing.
Most importantly, tyre model is something that should define a max slip angle that could be reached with that tyre and that's not happening with GP Bikes.
What I meant when I say that, is that I'm not sure if this "unrealistic dragging of the front tyre" is caused by slip angle being calculated in the phys. engine (because as noted by Stout Johnson it indeed doesn't look like regular slipping or the tyre) or it is just some "game magic" overlayed on physics and causing this dragging. Anyway it's very wrong and remains a problem.

So as the bottom line: I don't doubt that slipping is modelled in the phys. engine, that's something that I checked first hand while playing with tyre characteristics. I doubt that this weird slipping is the same kind of slipping as "normal one" happening because of the tyre flex, while generating force.

But I am not sure whether this is a good title for the behaviour, as I doubt that there is actual front wheel slip happening. What we see is the front wheel somehow being dragged unrealistically which in reality would have translate to front wheel slip. But in GPB I assume it is rather a visual/geometry/resultant force bug which causes it to look like front wheel slip.

You are right, that's something we already figured out here. I'm also not sure if real slipping is happening or not in the game engine, but its definitely not related to slip angles being defined by the tyre spec.
Anyway, I called the topic like that because visual position of the bike in relation to the surface IRL is determined exactly by front to rear slip angles relation, that's why "unrealistic front wheel slip" was the first logical assumtion.

i can make a replay of it, but a replay is not going to give you the feel  of what is happening, so that's useless.
and it definitely feels like the grip is actually forcing me over, it doesn't feel like a front washout.

Please make one if you can, I'm very good at looking at replays..) Just beetter make 2: tank view and outside (auto).
+

and it definitely feels like the grip is actually forcing me over, it doesn't feel like a front washout.

Does this sudden grip force your front out or inside the turn?

Max, so by that reckoning, then what is happening to me in this situation is correct?
am i just asking too much grip at too low/high an angle...?

         

Eventhough, I still don't fully understand what's happening I can tell you that what you describe sounds strange. In fact, front wheel never ever can wash away after you already started accelerating (that's possible only in the very first moment of opening the trottle on max lean angle, because of the front tyre instant unload).When you are already acelerating our of the corner - only rear tire can slip away.

Now a question for me: how can a front tyre crawl on the side if you'r picking up the bike? How can this happen geometrically-wise? I don't understand how can a front tyre start gripping in the B section if the section itself is fully determined by the lean agle, that's what's bugging me in your explanation.

i can feel the tire gripping nicely on the bottom side of the tire.
then, instead of gripping more onto the main tread of the tire as i try to lift and accelerate at the same time, it seems to start gripping more and more up the side of the tire, so that if i keep accelerating, it just 'bites' back down on the SIDE of the tire and causes the front to tuck in.(BITE in, more like) 

To be honest I don't quite understand the concept of "bottom" and "side" of the tire in your explanation. I mean: part of the tire gripping the ground depends on the lean angle so how side of the tyre can start gripping more if you'r lifting the bike out of the corner? I'm confused. 

Yea, I added it a "second" after the post) showing the last setup I tried, but yeah.. it's not really needed anymore after I made sure myself that the issue is not in tyres specification.