I have eliminated front end wobble 80%

[HornetMaX]

iv felt so far on gpbikes that in general the bikes understeer a tad too much..
feels more like the front end doesnt track properly to me though (like the bike pushes at an angle through the corner).

Thank you sir! I have always felt that way and even tried to make a case that this is a bug (http://forum.piboso.com/index.php?topic=665.msg6249#msg6249), but obviously not many seemed to not see a problem there (or maybe didn't understand what I meant). I still see this problem, mostly when accelerating on high lean angles...

Yep, I remember that discussion. Recently, reading the book that describes the tire model used for GPB, I've found this:

A draw-back of the adapted formulae is the fact that at a given large value of alpha or gamma the asymptotic level of the side force that is approached at increasing large value of gamma or alpha respectively may (unintentionally) become (much) too low.

In the above, alpha is the sideslip angle of the tire while gamma is the camber angle. What the above means is that when both alpha and gamma are large, the formula used may underestimate the lateral force the tire generates. In practice, on a turn with the bike leaning significantly and the front tire "not pointing in the direction of motion" (i.e. significant sideslip angle), the front tire could generate less lateral force than it should. That could be the "poor tracking" bob is referring too (and somehow related to what we discussed Stout).

As the above applies to the rear tire too, I was also wondering if the fact that the asymptotic side force in such situations is too low could also play a role in the fact that powersliding is so difficult to control properly.

It's mostly speculation though, as we really can't investigate this properly, only Piboso can.

MaX.

[Vini]

I know what you mean.
For example on Mugello (turn 8 and 9) it looks weird.

[Stout Johnson]

Yep, I remember that discussion. Recently, reading the book that describes the tire model used for GPB, I've found this:

A draw-back of the adapted formulae is the fact that at a given large value of alpha or gamma the asymptotic level of the side force that is approached at increasing large value of gamma or alpha respectively may (unintentionally) become (much) too low.

In the above, alpha is the sideslip angle of the tire while gamma is the camber angle. What the above means is that when both alpha and gamma are large, the formula used may underestimate the lateral force the tire generates. In practice, on a turn with the bike leaning significantly and the front tire "not pointing in the direction of motion" (i.e. significant sideslip angle), the front tire could generate less lateral force than it should. That could be the "poor tracking" bob is referring too (and somehow related to what we discussed Stout).

As the above applies to the rear tire too, I was also wondering if the fact that the asymptotic side force in such situations is too low could also play a role in the fact that powersliding is so difficult to control properly.

It's mostly speculation though, as we really can't investigate this properly, only Piboso can.

MaX.

OOOh nice info there MaX! (I guess it is a nice positive side effect that comes with you not having a gaming PC at the moment - you have plenty of time to read ) If I understand correctly, there is this formula to estimate the lateral forces of a tire (and this forumla is used in GPB) - and at high lean angles this formula may underestimate the forces right? This could indeed be the a cause of the "not pointing in the direction of motion"-problem.

But as for the powersliding control - you rarely have large lean angles when powersliding. At least they are very very hard to control anyway and mostly end in a high-sider irl. My assumption for the cause that powersliding is so hard to control, imo seems to be that the virtual rider seems to need a fine-tuning for such on-the-edge situations. It is the same when you try to get trail-braking to work... The initiation works, but then the virtual rider always seems to make a counter-steer which counterfeits a long powerslide/trail-brake. If one continues with the applied acceleration/brake it seems to build up due to the reaction/counter-reaction of the virtual-rider (it is very visible in slo-mo replay - the rider goes left/right/left/... although I have steering/leaning constant [using auto rider lean ofc]) and ends in a high-sider/crashes. If one adapts and releases throttle/brake a bit you can save it but only have minor powerslides or trail-braking situations.

[HornetMaX]

OOOh nice info there MaX! (I guess it is a nice positive side effect that comes with you not having a gaming PC at the moment - you have plenty of time to read )

Actually I read it before moving from scotland, but it's true it was at a time where I had a lot of time.
I didn't want to discuss it here immediately because I wanted to do some tests before (and also because I'd need Piboso to at least have a look at the curves I get to confirm I've implemented the formula correctly, didn't seem quite the right moment for that), but then the discussion re-surfaced so here it is

If I understand correctly, there is this formula to estimate the lateral forces of a tire (and this forumla is used in GPB) - and at high lean angles this formula may underestimate the forces right? This could indeed be the a cause of the "not pointing in the direction of motion"-problem.

The formula may be wrong for high lean and high sideslip at the same time. High lean only is not enough (nor is high sideslip only).

But as for the powersliding control - you rarely have large lean angles when powersliding.

One thing that I'm not sure is what "high" means in this context. I'm under the impression (from the usage of "high" done in the book) that in the book "high lean" could be even something as low as 20 degrees (and maybe even less). It's "high" compared to "no lean at all", meaning the behavior is significantly different from the no lean situation. This means you don't need motogp-like leaning of 60deg to be in trouble.

MaX.

[rodney007]

Its interesting listen to you guys woffle on about so much stuff.

No-one is yet to even try what I have suggested to edit.

For the record, The throttle effect doesn't matter if you have a R6 club bike or a 2014 motogp bike. The physics are the same,
The compression is barley noticeable on a GPbike because of there space-technology suspension that must resist such power and
torque.

Here is a short clip of me testing my new suspension some years ago: (managed to shave 5 secs off these laps later)

https://www.youtube.com/watch?v=gxbjR3Era_E

See: 0:22, 0:45, 1:28 are few good examples.

Same thing happens with any bike... now before we go talking about other stuff again just try my
file edits to the tyre and see what you think!

[BOBR6 84]

Lol 

Im not gonna mess about with files etc.. That would end in tears..

If you can upload a file to download im intrested to try it out for sure!!

[Hawk]

Its interesting listen to you guys woffle on about so much stuff.

No-one is yet to even try what I have suggested to edit.

For the record, The throttle effect doesn't matter if you have a R6 club bike or a 2014 motogp bike. The physics are the same,
The compression is barley noticeable on a GPbike because of there space-technology suspension that must resist such power and
torque.

Here is a short clip of me testing my new suspension some years ago: (managed to shave 5 secs off these laps later)

https://www.youtube.com/watch?v=gxbjR3Era_E

See: 0:22, 0:45, 1:28 are few good examples.

Same thing happens with any bike... now before we go talking about other stuff again just try my
file edits to the tyre and see what you think!

Lol 

Im not gonna mess about with files etc.. That would end in tears..

If you can upload a file to download im intrested to try it out for sure!!

Hi Rodney.

Bob is right. Most people can't get their head around messing about with the physics files. If you want people to try your theory/results it's best to just provide a download link for an altered physics file so that others can just copy past it into the bike file required, then you'll get people testing what you have done. 

This does sound very interesting..... Hope you'll give us a download link so we can try. 

Hawk.

[HornetMaX]

Its interesting listen to you guys woffle on about so much stuff.

No-one is yet to even try what I have suggested to edit.

For the record, The throttle effect doesn't matter if you have a R6 club bike or a 2014 motogp bike. The physics are the same,
The compression is barley noticeable on a GPbike because of there space-technology suspension that must resist such power and
torque.

Here is a short clip of me testing my new suspension some years ago: (managed to shave 5 secs off these laps later)

https://www.youtube.com/watch?v=gxbjR3Era_E

See: 0:22, 0:45, 1:28 are few good examples.

Same thing happens with any bike... now before we go talking about other stuff again just try my
file edits to the tyre and see what you think!

I would try them, but at the moment I can't (no PC available for a few more weeks).

However, you are wrong: squatting when accelerating doesn't happen for any bike. I may trust you it happens on your, but that's not the case for any bike. I have books with world-known researchers and bike experts stating this (I mean, it's not my word you should take for granted). A less technical explanation, click on the link and search for the paragraph "Does the rear actually RISE under acceleration?": http://www.promecha.com.au/myths_misconceptions.htm

BTW, you didn't answer my question: do you actually know what are the parameters you changed, what they mean physically ?

MaX.

[rodney007]

Its interesting listen to you guys woffle on about so much stuff.

No-one is yet to even try what I have suggested to edit.

For the record, The throttle effect doesn't matter if you have a R6 club bike or a 2014 motogp bike. The physics are the same,
The compression is barley noticeable on a GPbike because of there space-technology suspension that must resist such power and
torque.

Here is a short clip of me testing my new suspension some years ago: (managed to shave 5 secs off these laps later)

https://www.youtube.com/watch?v=gxbjR3Era_E

See: 0:22, 0:45, 1:28 are few good examples.

Same thing happens with any bike... now before we go talking about other stuff again just try my
file edits to the tyre and see what you think!

I would try them, but at the moment I can't (no PC available for a few more weeks).

However, you are wrong: squatting when accelerating doesn't happen for any bike. I may trust you it happens on your, but that's not the case for any bike. I have books with world-known researchers and bike experts stating this (I mean, it's not my word you should take for granted). A less technical explanation, click on the link and search for the paragraph "Does the rear actually RISE under acceleration?": http://www.promecha.com.au/myths_misconceptions.htm

BTW, you didn't answer my question: do you actually know what are the parameters you changed, what they mean physically ?

MaX.

I know what the parameter does to effect the bike, in terms of puting a name to it no. I went through each line with positive and negative values then tested.

In-terms of your research. Sure it makes complete sense - though the games result on suspension will not equal "real lifes" effect on the line radius.

Motogp bikes suspension compresses in corner and on a straight. If you don't know this watch some onboard footage.

Hi Rodney.

Bob is right. Most people can't get their head around messing about with the physics files. If you want people to try your theory/results it's best to just provide a download link for an altered physics file so that others can just copy past it into the bike file required, then you'll get people testing what you have done. 

This does sound very interesting..... Hope you'll give us a download link so we can try. 

Hawk.

Download the Yamaha M1 for 5b,

Unzip these files into the bike folder (backup)

As I said race some laps first so you can feel the change best.

https://www.dropbox.com/s/3ktq7z2n4epl63q/Yamaha%20YZR-M1.zip

Please just try it, motorbike physics are a science on their own... I have been caught up in arguments in real life and there is never a winner.

[HornetMaX]

I know what the parameter does to effect the bike, in terms of puting a name to it no. I went through each line with positive and negative values then tested.

In-terms of your research. Sure it makes complete sense - though the games result on suspension will not equal "real lifes" effect on the line radius.

Motogp bikes suspension compresses in corner and on a straight. If you don't know this watch some onboard footage.

Hmm ... OK then. Good luck.

MaX.

[BOBR6 84]

just tested it.. thanks!

it has to be said.. feels awesome!!!

front end has bags of feel and grip.. no wobbles only nice wobbles.

bike turns alot better.. generally feels great! lol

weather its right or wrong i have no idea but i like it alot lol

only thing is... do not crash because the game crashes in a nasty way..

[FastFreddy]

https://www.dropbox.com/s/3ktq7z2n4epl63q/Yamaha%20YZR-M1.zip

Bad irrealistic feeling. Change some numbers at random will not make better gp bikes. Even in this case.

[rodney007]

https://www.dropbox.com/s/3ktq7z2n4epl63q/Yamaha%20YZR-M1.zip

Bad irrealistic feeling. Change some numbers at random will not make better gp bikes. Even in this case.

This is why I was hesitant to offer my findings

[girlracerTracey]

https://www.dropbox.com/s/3ktq7z2n4epl63q/Yamaha%20YZR-M1.zip

Bad irrealistic feeling. Change some numbers at random will not make better gp bikes. Even in this case.

This is why I was hesitant to offer my findings

It is the easiest thing in the world to post undiplomatic comments on a forum of this type. We can all do that. If we choose to..

Rodney, please do not be dissuaded. Experimentation of this type is in my opinion a worthwhile exercise. For it is only experimentation. What is the harm in that? You never know experimentation of this nature might provide some of the answers we are searching for..

I will try your modification for myself later on today.

Furthermore your bike mods are I have to say a very worthwhile contribution to the gpbikes community. I for one cannot wait to sample your TZ750 and its physics model.

grT 

[Hawk]

https://www.dropbox.com/s/3ktq7z2n4epl63q/Yamaha%20YZR-M1.zip

Bad irrealistic feeling. Change some numbers at random will not make better gp bikes. Even in this case.

This is why I was hesitant to offer my findings

Hi Rodney.

Don't worry about it.... You'll always get those who will denigrate your findings or think they know better. Same you will get others who think your changes are great....  Others like Max will try to look at your findings and work things through with you to fully understand what you have done and it's effects. So just make your tests and post the results/files(like you now have done.) for everyone to give it a good test. If people don't like it then so be it, no problem at all. If you get a community consensus and the backing of the bike MOD authors then who knows, your changes may even be added to the bike MOD/s.

So really, don't worry about what others think, it's just part and parcel of what forums are about(debate and differences of opinion), and this is a great forum. At least your giving it a go and testing things and trying to improve things.... Good on you mate I say!   

Hawk.