I remember 13180 as WR at one time but don't remember less than that - maybe before my time

I remember going on a server after being absent for a long time and someone checking my current pb and seeing it 1326x when WR was about 13330 and declaring that I must be a cheat I had a hard time explaining to him it was from an old patch that was before they were reset.

Quote from lEl E Talon :

where does 1.8% come from?

It's the difference between fastest and slowest laps of a session that amp88 posted data for.

If the lap times were random I'd agree with shot but as there appears to be a clear trend in each session towards slower times over each consecutive lap I think it is fairly strong circumstantial evidence that the tyres do tend to "go off" over the duration of a typical stint. I don't think it is because of overheating tyres though and tend to think it is primarily to do with the change in the tyre over the stint, both in the chemical and mechanical structure of the tyre.

'70 Toyota Corona, '83 Holden VH Commodore, '86 Holden VL Commodore, '71 Toyota Corolla, '74 Ford Escort, '84 Ford Cortina, '88 Holden VL Commodore, '85 Ford Telstra, '90 Suzuki Vitara, '72 Datsun 120Y, '86 Mitsubishi L300, '89 Hodlen VN Commodore, '90 Ford Falcon, '99 Ford Fairmont, '08 Holden Commodore... That's the ones I can remember I think I've missed a few

http://www.bayarearidersforum. ... thread.php?postid=2568292

This is info about motorcycle tyres but interesting info still.

Quote from mrodgers :

Well, when it's youtube and you expect 3 pages of "WTF!!!!111!!" and "First I was..... Then I was..... and then I was....", you don't bother with spending the time scrolling through the pages on the very slim hopes that 1 comment was actually intelligent.

Which is when I employ the binary chop sort method

Quote from amp88 :

^ From the YouTube comments (username burmotec).

Looked like the right rear wing support failed resulting in the snap oversteer. Very big crash...surprising the driver was unharmed.

Meh page 3 of comments which I found even before I read past the op first post - reading can't be totally lost then heh

Perhaps one of the big differences to real life vs LFS is that tyres in rl reach an operating temp (depending on how aggressive the driver is weather or not that temp is coolish, in the optimum range or abit hot) and are then quite stable with a slight cooling off as the tread wears down.

Were what we currently see in LFS can be a trend where temps keep esculating instead of stabalizing once the have reached a certain level. This could simply be due to the yet incomplete simulation of tyre wear and damage under aggressive driving conditions. i.e. when driving at the limit the surface of the tyre should be getting quite hot but in this state it will also be experiencing rapid wear - if this were to happen in LFS that could mean a reduction in transfer of heat from the surface of the tyre to the inner core of the tyre.

This would then mean that a greater portion of the core temp would be generated by molecular exitment of the rubber rather than by heat transfer causing the tyres to take longer to heat at the core and also to be more stable at operating temp.

It apears to me that alot of the grip loss experienced in rl is caused by a change in tyre chemistry (i.e. flex, softness - characteristics in general) of the tyre over it's life span, equally if not more grip is lost by wear of the tyre (i.e. graining, chunking etc) having an impact on contact patch area. Not so much by temperature as in LFS as these other issues are far more pronounced and have impact long before temperature can have the sort of imact as it does in LFS.

amp88 could you please post one more lot of data for perhaps the M3 as that appears to have been a better handling car with more consistent runs and even tyre wear just for comparison? Don't be lazy

Last edited by Glenn67, Wed, 20 May 2009 23:04.

yeah I was thinking that that graph also wasn't exactly scientific but to serve only as a guide to how different tyres behave. Cold tyres certainly have more grip than zero

Quote from amp88 :

It was actually Winton

Attached it too.

That's it I knew I could rely on you! I wouldn't suggest that graph as being highly scientific but it does serve to illustrate that tyres do "go off" some worse than others depending on compound and tyre design.

Looking at the tyre from first and second stint it does look like there is a correlation to tyre wear/damage vs lap time also. This is were LFS is odd when towards an end of stint when tyres are cooling more you can work them harder and get the fastest lap times were in real life it is more likely that graining wear and damage to a tyre would result in worse lap times in this phase even though temps are less.

It is interesting that the graph you posted for temp vs traction does show a signicifacnt leveling out in the overheated region and that they don't bother graphing above 127degC which would indicate it's hard to get a tyre that hot - possibly due to tyre failure?

Last edited by Glenn67, Wed, 20 May 2009 12:20.

Again more interesting data...

You can see that the times from both stints degraded over the length of the stint and also that the second stint was slower than the first in general. This correlates to the aging of rubber exposed to heat as much if not more than from mechanical damage One would suspect that with the much higher tyre temps on the front in the first stint that was when it suffered chunking of the tyres. Do you have data from any of the other cars or more commentry of when the tyre sustained the physical damage?

Did you catch the coverage of V8Supercars which showed the graphs I refer to? Think it was Oran Park round (memory fails )

The graph you show only indicates temp and shows what I'd expect from different compounds, it would be interesting to see a graph that measured traction verses age of tyre.

Quote from ColeusRattus :

Well, that's a phenonemon limited to oval racing then.

Well no, add to that the V8Supercar serries... they posted some clear graphs of lap time degradation over a stint. Their normal control tyre can expect to see a second a lap difference from start of the stint till the end. They also have a sprint tyre they can run with much softer compound that has much more dramatic degradation of lap times over a stint of the same length.

Interesting post amp88, the evo tyre looks like it has suffered quite abit from overheating on the shoulder and a little on the edges of the tread blocks. It is suprising it didn't effect his lap times more.

My understanding though is that road tyres should be more stable in their chemical makeup than a race compound and therefore I'd expect it to have less performance drop off than a slick or true race compound. Did they have times from both stints?

Quote from sidi :

......i got old and slow

Hey you would never let me get away with pulling the age card!

Mercury has certainly a lot to be proud of, congrats on a successful 5th anniversary.

I still have good memories of the early days first with SRT then Team[400] servers and the many fun nights with vince, storm, viper, deadeye and sidi to name a few

Sidi I particularly have great respect for your fairness and the way you have conducted yourself over the years.
Vince (although I doubt he remembers lol) for helping me several times back in 2004 by doing laps with me and coaching on TS
Paul2k although I haven't had the opportunity to know you, I have great respect for how you have managed the team over the years with the various challenges you have had.

While your achievemnets have been outstanding on the track it's the people that have made it truely an exemplary team, I wish you all the best guys

Quote from Jamez08 :

Haha, point taken. I usually block out 95% of what OBP has to say anyway.

yeah Sam can be a bit of a chatter box when he gets going, but he is good value

How do you know his experience or knowledge level?

I've been running XP Pro since it was first released (NT before that), and while I have been happy enough with the stability of those OS's I have always played with the idea of changing to a Linux based OS. Have tried on a few occasions over the years but always found it too hard and reverted back to what I know.

About a month ago my XP install appeared to have been hacked, so I decided "stuff it I'll give Ubuntu 9.04 a serious go" I chucked in a new hard drive and proceded to do a fresh install.

It wasn't entirely without incident but went more smoothly than I expected, I am very happy with Ubuntu for my daily tasks (i.e. spreadsheets, email, wordprocessing, database, internet, etc) and was suprised how quickly I was able to adapt to the new environment. I haven't tried to run LFS or other games though and don't intend too, will be getting a second PC shortly for LFS.

Things I did and didn't do.
Did - search for possible problems that linux might have with my hardware (i.e. typed in my m/b chipset and linux as key words to a search to see what experiences others had had)
Didn't - plan or organise for the change in a smooth manner. I just bit the bullet and went with it, something I wouldn't normally recommend. I did it almost as a test to see if Ubuntu has improved over early versions.

The only issue I had was with the install - it took me about four failed attempts before I figured out that Ubuntu had a problem with my graphics card, once I worked out how to install with safe drivers it all went like a dream.

I think Ubuntu is a stable, fast and easy to use OS has extensive amount of quality software available and best of all it's free.

Here are some articles that a few might find interesting...

http://tyres.wordpress.com/200 ... tyres-and-the-grand-prix/

http://tyres.wordpress.com/2007/03/19/tyres-and-formula-1/

http://espace.library.curtin.e ... 0112&local_base=GEN01

Last edited by Glenn67, Tue, 12 May 2009 14:32.

Quote from Bob Smith :

a) It's likely that, at the level of motorsports that are televised, such mistakes are very rare in the first place
b) The drivers' level of skill is enough that you don't really see much difference from an external point of view
c) Anyone outside the pitlane likely has no idea about how hot tyres may or may not be during a race in the first place

This isn't defending LFS, you just can't make such circumstantial comparisons meaningful.

Add to that that for any given race serries the choice of tyre compounds etcetera have been sorted and therefore having overheated tyres is less likely than perhaps what we see in LFS

Quote from Matrixi :

Thanks mate, that did the trick. 6 years in and still learning new things!

Still doesn't explain the very hot tire grip levels though.

Wasn't going to mention the 2003 registration and not knowing thing

When tyres get too hot the surface rubber melts this is evident when a driver flat spots a tyre i.e. less grip - longer baking distance and rapid localised wear -flatspot. It also shows up in other forms such as blisters which are detrimental to tyre usefulness and life.

I think that the surface temps in LFS do approximate what I'd expect to happen in real life but I don't think the core temps are a good approximation of real life tyres.

The heat model seems to be centered around frictional heat, while this is accurate for suface temps I don't believe its a good model for the core temp of the tyre carcuss.
Rubber is actually a good insulator and hence the surface temp and core temp can be very different for extended lengths of time throughout a race. The core temp should be predominately influenced by the stresses passed through the tyre rather than the surface temp of the tyre radiating inwards.

For these reasons I suspect LFS tyres tend to heat too quickly and also often heat in an unbalanced way i.e. driven wheels can maintain temp well while the non driven wheels often remaining less than optimum. This is also why you often hear that the fastest way to drive in LFS is to slide the car around more than you would in real life and why you see hybrids on the rear of the GTi etc, etc. Because the core temps are so closely linked to the surface temps the surface temps I believe tend to esculate at a much faster rate than what would happen in real life.

On a side note - tyres will tend to give there best performance early in there life cycle, this is because the chemical make-up of a tyre is continually undergoing change thoughout its life cycle. In the coverage of the latest round of V8Supercars at Winton they threw up a few interesting graphs of tyre performance of a 20 lap stint. The standard control tyre would see it's fastest lap time in the first few laps and have dropped off by 1-2 sec a lap after 20 laps, while a soft sprint tyre was much faster upto 2 sec a lap faster over the control tyre its degradation was much more severe. At the end of 20 laps the sprint tyre would be 2 or more sec slower per lap than the control tyre.

Press f9 to display tyre temps (tyre body temp) then while tyre temps are being displayed hold down ctrl-shft to view surface temps.

Many people that play LFS don't really care for graphics as much I personally have a fast enough PC with good broadband but I have dl skins turned off all together and race with white cars mostly. It's not about the money I'm probably an extreme example but you get my drift.

Also the way it is now will scale with high res skin usage well enabling the dev to cover some of the bandwidth costs. Are you proposing that if you race alot on populated servers that you should pay alot more than most as you skins will be getting downloaded more? Because thats how it will need to be to be consistent with the current way its done.

Torana XU1 with a Holden VL turbo motor

http://www.uniquecarsandparts. ... den_torana_lc_gtr_xu1.htm

Wouldn't it be better if a large percentage of people worked from home?

We are meant to be in the information age are we not? So why do so many commute to and from work each day? I would have to think that there is huge potential to cut immissions by simply enabling/allowing information related workers to work more from home. I know some that already do but I'm sure it's only a small fraction of whats possible. There needs to be a major shift in concept of what constitutes a work environment and how we as individuals go about daily business. It has started but it has a very long way to go..

Quote from Gener_AL (UK) :

Sorry to point out you Glenn

I was bored... what can I say

First off let me say I respect all drivers that have or have had WRs, I also respect fair drivers and just about anyone else unless they are being a total dick

I'm with you in not liking going around in circles. I tend to ignore most comments about such things as "exploits", I myself have enjoyed LFS in many forms - some more realistc some less and have been able to have exciting races in all formats.

BC is one of those topics though that alot of myths and half truths abound in regards to it and unfortunately I find myself compelled by some un-natural force to type a response even though I know I would be better off not responding and keeping to myslef :Kick_Can_

I agree that it would be cool to have hotlap charts that could be filtered for different controls - maybe that would even encourage more people to break away from the norm

As for the circular arguments I think that comes about because LFS is unfinished as much as any other reason i.e. it does and will have bugs from time to time... some which are found and rectified quickely others that aren't so apparent and or take longer to fix.

Quote from arrowkart4 :

err, well burnout said button clutch is not faster, which is just stupid

The button clutch is not faster but it does net faster lap times

Quote from Becky Rose :

I hate very little, I either love things, am abivillent, or petrified. I seem to be missing the hate part of the spectrum.

I think that has someting to do with age hating is just too much effort for me

Quote from Overboard Productions :

Hello Fellow LFS Drivers.

G'Day m8 good to see that your doing well with the project! I hope you see it's full potential. I'm currently on forced leave of LFS but when I return I will be sure to visit