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Suspension set up not working

Started by KG_03, October 09, 2017, 07:09:47 PM

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KG_03

October 09, 2017, 07:09:47 PM Last Edit: October 09, 2017, 07:21:17 PM by KG13
There is a problem with suspension set up. Rebound and compression damping do not work at all, and it has big consequences on bikes.

In short form:
Each movement on the bike causes rapid suspension compression and decompression and the bike acts like a ball. It has an impact on the bike behaviour because each faster direction change cause the bike going up and loosing grip of the tires - mainly front. The issue can be mainly visible for game pad uses that can change direction faster unlike using wheel where it is easier to make it smooth. I have tried to smooth out the release button to 100% and the problem still exists but has less impact. Unfortunately the lighter the bike the problem is bigger.

I have tested the problem in this way:
Track Victoria. Bikes - Original 125 and GP1000 bike. I have set the rebound and compression damping to 1 done some laps and then to 11 (both parameters) and also did some laps. There was a very little effect, I'd say there was none. The lighter the bike the problem is bigger. 125 cc jumps like a ball and in chicanes it almost always looses grip. The only way is to go very slow and smooth. Unfortunately in DEMO version there is only one bike - 125 and its the one most affected. I think that fixing it will let acoid frustration of possible new players who have to struggle with this problem in their early steps.

Here is video of the problem:
https://youtu.be/Ve8o3gQ_JuQ
Each direction change causes very fast decompression of suspension. No matter how fast it is done . The effect is inapropriate front tire load which losses grip becuse fast decompressed suspension pulls front wheel up.


In longer form:
I had a problem because each time I have changed the direction the bike was jumping like a ball. The biggest problem was in chicanes where I always lost seconds because I had to be very smooth and slow not to loose front end. In real life I would set rebound damping to higher to avoid too fast decompression that will cause instability in corners or even give softer spring. But here there is no such option. One of the solutions I found is to slightly brake in turns, when changing direction and to set smooth release to maximum. But for me its temporal solution. Ok I know that in real life racers move body weight to upright position as last thing to avoid suspension decompression and grip changes. But here it happens too fast. As seen in video posted above each turn gives significant changes to suspension.

Suggested solution:
Fix the compression and rebound damping
Returning to upright position should be affected by speed and bike setting. At this moment no matter if I ride 300 kph or 50 kph the bike leans and goes upright with the same speed. Wheelbase has no affect in this matter. 


janaucarre

Hi,
One of solution can be changing the range, for example :
In txt file of the bike, dont know if we have this, put 100 in place of 10 and try it.
Dont know if this change the scale or if it divises the 1 to 10 in 100 parts.

KG_03

Ok I will try. I have found one more thing that might help in supersport class. Turn with throttle idle or throttle up so the front wheel will go up (helpful in slow corner exits) in all other situations the front will jump up 🙁

janaucarre

Hi,

I made some test until now and you can download the three murasama_rc990_03.cfg i transformed with other suspension settings that can be possible.

- Extract the bikes.pkz and put ther extracted files in the bikes folder (GPBikes/gpbikes/bikes)
- Take the bikes.pkz, cut it and past it elsewhere, on the desktop for example
- Put one of my files, rename it in "murasama_rc990_03", in the GPBikes/gpbikes/bikes/murasama and replace the existing one
- Try in game and look the front supsension settings, now you must have 20 possibility for bump and rebound

Each of these three files are differents, you can look at
"front_suspension"
                           "Damper"
                                         "Bump"


AND

"front_suspension"
                           "Damper"
                                         "Rebound"



KG_03

October 09, 2017, 11:35:54 PM #4 Last Edit: October 16, 2017, 04:19:08 PM by janaucarre
Thank you ! I have tested all of the files. The third one seem to be the best of them....but still the effect is a bit too explosive even if I set the damping to 20. I wonder how will it look like if I set it to 40... will the fork go slower to its initial position and slower compress?
I don't know the structure of the suspension code but I would double the strengh of rebound and compression damping. Still with hardest springs and hardest compression damping at hard braking there is exclamation mark, and when I release the brake the front rapidly moves up. Murasama is very easy to ride, the suspension issue was mostly visible at lighter 125/Moto3 bikes.

This video shows abit what I mean:
https://www.youtube.com/watch?v=jj2BRE0Unck
It looks like the motorcycle in GP Bikes rebounds too fast no matter how I set it.
Or here:
https://www.youtube.com/v/mJV-jhEtjz4
<- front suspension damping
https://www.youtube.com/v/=SXDL_jREhEE
<- I miss that slower compression/rebound effect as shown at the start of video.



janaucarre

Hi,
try this new one, i double the values.

KG_03

October 10, 2017, 04:41:25 PM #6 Last Edit: October 16, 2017, 04:20:10 PM by janaucarre
Fantastic! Thank you :-) As for the configuration file nr 4
In my opinion rebound damping set to 15 should be the zero value (no damping at all) value 20 (middle setting setting) value 25 or even 30 maximum damping. Same for compression.
I feel bad because I take your time, and still not fully satisfied..Im really sorry. Maybe there is way I could change the settings by my own not to bother you and present the results after testing ?
I attach video from maximum rebound and compression setting with medium spring, when changing directions with little throttle aplied, so there was similar compression to both suspensions. Is it possible to give similar settings to rear suspension (rear decompress faster then front and the setting allows only value 11)
https://youtu.be/eWdXSa7NykI



janaucarre

no problem.
you can change all what you want, the part you need is bold (look next)
Try as many as you need.
There is the same settings for rear suspension next to front suspension (in the txt file), i didn't change anything to the rear.
I don't know what are these data but for sure someone here will answer if you ask.
Waiting your results.
Please note that it probably can't be the same scale/range for other bikes.


front_suspension
{
   Mass = 4.25
   InertiaBox = 0.4, 0.4, 0.4

   Spring
   {
      range = 10000, 500, 13000
      setting = 4
   }

   Area = 0.0016
   AirLengthBase = -0.055
   AirPressure = 100      ; kPa
   Oil
   {
      range = 0.08, 0.01, 0.14
      setting = 3
   }

   Damper
   {
      BumpThreshold = -0.1
      Bump
      {
         setting0 = 0, 100
         setting1 = 200, 180
         setting2 = 400, 260
         setting3 = 600, 320
         setting4 = 800, 400
         setting5 = 1000, 480
         setting6 = 1200, 560
         setting7 = 1400, 620
         setting8 = 1600, 700
         setting9 = 1800, 780
         setting10 = 2000, 860
         setting11 = 2200, 920
         setting12 = 2400, 1000
         setting13 = 2600, 1080
         setting14 = 2800, 1160
         setting15 = 3000, 1220
         setting16 = 3200, 1300
         setting17 = 3400, 1380
         setting18 = 3600, 1460
         setting19 = 3800, 1520
         setting20 = 4000, 1600



      }
      BumpSetting = 6

      ReboundThreshold = 0.15
      Rebound
      {
         setting0 = 0, 260
         setting1 = 100, 300
         setting2 = 200, 340
         setting3 = 300, 380
         setting4 = 400, 420
         setting5 = 500, 460
         setting6 = 600, 500
         setting7 = 700, 540
         setting8 = 800, 580
         setting9 = 900, 620
         setting10 = 1000, 660
         setting11 = 1100, 700
         setting12 = 1200, 740
         setting13 = 1300, 780
         setting14 = 1400, 820
         setting15 = 1500, 860
         setting16 = 1600, 900
         setting17 = 1700, 940
         setting18 = 1800, 980
         setting19 = 1900, 1020
         setting20 = 2000, 1060


      }
      ReboundSetting = 6
   }

KG_03

Thank you! 😀
What program do I need to edit cfg file?
And shall I pack the whole bike files again to pkz to make em work?

Syd

Good luck with this KG13, I have a feeling you are on the cusp of something big here!

janaucarre

You only need wordpad It's in every windows

Napalm Nick

Quote from: KG13 on October 10, 2017, 07:27:37 PM
Thank you! 
What program do I need to edit cfg file?
And shall I pack the whole bike files again to pkz to make em work?

My tip is to not unpack the files but to work directly from the pkz (in effect a zip). Click to list files in your zip program and double click file to open it and amend it in notepad/wordpad then save it back. All stays in a pkz prefix then.
"The post you are writing has been written at least ten times already in the last 15ish years. Its already been reported, suggested, discussed, ignored or archived (but mostly ignored). Why are you doing it again?"

KG_03

Quote from: Syd on October 10, 2017, 07:43:35 PM
Good luck with this KG13, I have a feeling you are on the cusp of something big here!

I'm very motivated, but need to figure out if my expectations can meet possibilities :-)

Thank you janaucarre and Napalm Nick :-)

KG_03

Mwahahaha I am master of the suspension :-D  just kidding - anyway I have copied bump values to rebound and front wheel in hardest setting is not poping up anymore :-D
I will try to base my modifications on Ohlins suspensions  :-D
https://www.ohlins.com/app/uploads/world/2017/05/MI_FKR120_0.pdf

BTW can anyone explain me what both values do the first one and the second one in the row?

setting0 = 3000, 1220
I mean what describes number 3000 and what 1220 ?


Napalm Nick

Slow and fast damping Forces as applied to either bump or rebound distance - (in newtons x acceleration?)



"The post you are writing has been written at least ten times already in the last 15ish years. Its already been reported, suggested, discussed, ignored or archived (but mostly ignored). Why are you doing it again?"