The online racing simulator
Clutch temp info
(106 posts, started )
#76 - FL!P
Yes, this is with the FBM. I already use this method, pulling the paddle first and lifting off the throttle to switch gears, but thanks for the suggestion.

Dunno, maybe it's my throttle pedal that doesn't cut completely, sometimes.
I ran half a lap of Westhill in the UF1 purposefully stopping, then starting with extreme slipping of the clutch. I started, slipped the clutch purposefully through all the gears, stopped and repeated. That was half of a Westhill lap. I saw very very little heat in the clutch.

The second half of the lap, I moved to 4th gear and ran the rest with the throttle floored and the clutch halfway engaged. It wasn't until I was completed with the full lap that the clutch had enough heat in it to slip when fully engaged.

How are people overheating the clutch with just a single race start? Or even with poor shifting through a race? My Westhill lap had to have been the absolute worst thing you could do to the clutch and never would have happened during any normal driving or racing, yet it still lasted through a whole lap.

If you let the clutch slip as I've seen some folks posting videos of (JTbo?), you are guaranteed to burn it out. If you drove like I drove the Westhill lap, you are guaranteed to burn it out. How you are burning it out with just a race start or throughout a race is beyond me.
Quote from kaynd :I have been in situations going up a steep hill with many cars in front of you starting and stopping. You basically slip the clutch all the way up…
Also it is possible to keep the car stable stopped on a small hill by slipping the clutch in low rpm.
I know people doing that a lot, almost in every traffic light, and no one had any problems whatsoever… (I don’t like doing it because I know it stresses the clutch with no reason) I bet none who knows about car abuse that happens a lot when you are around 20-30yold… experienced the clutch getting loose so fast.


In the attached replay you can see the CT bar that gets red in 33 sec of sliping in around 2000-3000rpm with less than 1/5 of the clutch pedal release and less than ¼ of throttle @ an XFG…

Have you ever been in a trafic jam that lasts hours? if you had that kind of clutch in your car you would be off in 10minutes...

I could almost guarantee you that if you do the same thing with a real car, you could have this burning sensation inside the car even faster. You don't stand in a slope with clutch when you got 2000-3000 rpm, it will slip and smell. When pulling off maybe, but it doesn't take that long.

Not saying the clutch model is perfect. I still think it's not easy enough to stall, although starting on full revs and high gears seem to kill the clutch better than I first though. But having your revs all down below 300 and getting away with it seems a bit odd for me. Maybe the next thing on the list should be engine damage.

Quote from mrodgers :
How are people overheating the clutch with just a single race start?

Too long first gear and probably automatic clutch that leaves the clutch half open.


edit. Some clutch standing testing with automatic clutch, cbecause it can find the right point I can't. You can stand there quite a long time I think, had shorter gearing than the default setup and the red didn't feel that worn to be honest.

It's ridiculously hard to do that manually though, the revs just drop to zero like a rock some point. It might be because you can't feel the accelerations with your body of course.
Attached files
ZWR^vM.Pesonen_BL1R_XFG.spr - 30 KB - 156 views
Quote from mrodgers :
How are people overheating the clutch with just a single race start? Or even with poor shifting through a race? My Westhill lap had to have been the absolute worst thing you could do to the clutch and never would have happened during any normal driving or racing, yet it still lasted through a whole lap.

Why then you don't download the spr i attached above to see for yourself? and why don't you try tha same test with the XFG? i can see that there is not the same problem with all cars..

Pesonen i did download your spr to see what tests you did.

As for what you guarande, i have not timed for how long i have seen others keeping the car still by slipping the clutch, but it is a lot longer that a normal take off... the next time i am to a similar situation i hope i have something to video it...

[edit]

i saw your spr, you did the same test as me with the only difference, you are using the autoclutch which manages to keep the car still with something close to 1250 rpm...
I just did this manualy, and because i am not that automatic, you see the car going backwards when the clutch gets red... if after that you push the pedal flat the clutch slips and instantly heats up to the point that is completely useles, it is a matter of 2 sec after the ct bar goes red.
Quote from kaynd :Why then you don't download the spr i attached above to see for yourself? and why don't you try tha same test with the XFG? i can see that there is not the same problem with all cars.

Done. You held the car at a stand still with the clutch for nearly a full minute. What do you expect? Do you expect not to overheat a clutch disc by holding it at a standstill on a hill with the clutch and reving at 3000 rpms? Do you not expect that when the clutch is so abused like that, that when it does overheat and slips, moving the revs up farther would only induce more slip, thus heating it up more?

In comparison to what I wrote, I was saying that it was amazing that I was able to run and entire lap in the UF1 driving the way I did without the clutch slipping until the end of the lap. In reality, the clutch should have overheated much sooner with my test.

Sorry, I do not have a replay of it. Never thought to save a replay as I was only playing around and not trying to prove/disprove a point at that time.
Count it it. was less than 36 sec for the temp to go red… from then I did move the revs up further to show that the clutch was useless… I wasn’t trying to keep it cool. (note that you see the revs get higher but i do not increase the throttle i actualy decrease it a bit after the CT goes red...)

I haven't tested UF1's clutch... it may be way more durable.

Anyway i do not expect to keep cool. I expect the clutch heat up slower and have a bit more linear loss of effectiveness.

And if nothing of that happens, it would be good to change that CT bar so it’s range has to do with the effective temperature of the clutch... when the temp reaches half the bar, there is no clutch whatsoever so what's the point going further up? it could be focused to the working range of the clutch.

I said what I wanted to say. I stop here because I am giving wrong impression and I am not helping anything get better by repeating the same things.
I can live with the current clutch model.
Are the people that find clutches easy to burn all using lock diff?

I think you will find any high locking diff will now put alot more strain on the clutch causing it to overheat at least that is my impression.

The UF1 has an open diff most people driving the XFG are still probably trying to use the locked diff try the LSD with medium to low locking and see if your results are much different.

I agree though that the XFG does seem to be a little too sensitive.

A few comments though in a real life car slipping the clutch on a slope at average 2000 rpm isnt low rpm a normal hill start probably wouldn't use much more than 1200rpm if that, also first gear in a rl street car would be much much lower so less bite would be needed to keep car stationary.

But I get your point and yes I think it probably needs a little fine tunning. Like BBT said its probably just the heat curve that need fine tunning on some cars. And also people will need to adjust setups to siut new situation, and on thinking about it, its probably this later senerio that is more true as we have got away with quite unrealistic setup before.
To clarify that. and i am off
In my test, the XFG has 1ts gear that gives about 36km/h at 6000rpm… I wouldn’t call that a long gear.
Also I hardly believe that locking diff has an effect on that unless you take account the resistance which creates in slow speeds.
And because I do that test on stand still with the tires straight, the diff doesn’t affect anything.
After all that set has a clutch pack with 40% locking [edit]i checked again and i found that there is an open diff lol... i thought that there was the defaut's diff[[/edit] (anyway I hate locked diffs… I have removed them from all my sets for any car, since the addition of preload after patch W)
Quote from kaynd :anyway I hate locked diffs… I have removed them from all my sets for any car, since the addition of preload after patch W

I did the exact same thing
I do agree that the XFG clutch seems abit too weak, but its seems to be XFG related so probably just an adjustment on that car is needed. Also your probably right in that the friction heat build up is abit off at lower rpm, maybe accross the board haven't tested myself


One thing that has always bothered me in LFS is that mid to low rpm always "sounds like" its too low compared to RL. I mean if I go in my car and hold it at 2000rpm it sounds like 4000rpm in lfs or there abouts, so I think it gives a false impression that it is low rpm when its not. I have noticed an improvement in that in this patch but it still gives me that impression
#85 - JTbo
Just did 10 laps with XRG, after that 2 laps flat shifting and 2nd -> 3rd there is huge gap in this set, it took those two laps to heat up clutch have beginning of red even 2nd to 3rd shift was enormous slipping and I did make that shift quite often per lap.

No any trouble when driving normally.

Don't know about XFG, that is FWD and those I don't drive
this set is crap man it's an old attempt of me to make a road going stable set which i just took and lowered the first gear just for the test. lol there is no point driving it

[edit]
OMG I can't help mysefl i have to stop thinking about it
anyway just a quote

Quote from TomM :Also the clutch in the car is very easy to overheat. Two uses and its essentially overheated and unusable. You'd really have to ride the clutch for a lap to even notice a difference. Now, within seconds you can completely ruin it which isn't very realistic. I've never heard of a clutch on the FBMW going bad from normal use, let alone misuse, and there is definitely some misuse. I used the clutch on downshifts when I raced in 04 (then moved to GT cars and left foot braked, backwards I know) and had zero problems with the clutch.

http://www.lfsforum.net/showthread.php?p=623661#post623661

I hope that's my last word about clutch overheat.
I will try hard I promise
Yesterday I was online driving the new BMW, Lx6, F08, FZR and umm the 4wd gtr thingy and not once did the clutch heat up more than it did on initial driving off from the pits.

I don't understand how one can heat it up? Or is it the auto clutching? With 3 pedals and a H shifter for the cars who use it.. No issues whatsoever!
#88 - JTbo
Quote from Niels Heusinkveld :Yesterday I was online driving the new BMW, Lx6, F08, FZR and umm the 4wd gtr thingy and not once did the clutch heat up more than it did on initial driving off from the pits.

I don't understand how one can heat it up? Or is it the auto clutching? With 3 pedals and a H shifter for the cars who use it.. No issues whatsoever!

put auto clutch and 3rd gear in and floori it, keep it floored against pitwall, I guess that is only way?
I have noticed that under "normal" driving conditions, the clutch is fine, but if someone hits you in the behind, it heats the clutch up alot, also, if you spin off you tend to heat the clutch up alot too.
The clutch doesn't only wear out 2 times too fast, it wears out, or maybe I should say loses grip 2000 times too fast. I got stuck (and almost died, literally) in the "October storm" in Buffalo NY last October. I got stuck in a drift in my wifes 1995 200SX-Se-R with about 95,000 miles on it and the original clutch. A relatively light weight 140HP front wheel drive car. The car has a stock limited slip differential, but that only helped a little with the 205-50-15 tires in the heavy wet snow. I had to forward and reverse probably 300 times before I got it unstuck. I got that old clutch DAMN hot and I thought I was going to kill it, but at the time my life seemed more important so I kept rocking the car back and forth, spinning the tires, getting a little grip, slipping the clutch like crazy for about 2.5 hours. I finally got unstuck after using an ice scraper to shovel paths in the snow for the tires to get some grip while getting soaked to the bones in 30F degree weather.. I thought for sure I cooked the damed clutch, but guess what? On the 12 year old clutch in the 12 year old car after a night of horrible abuse, the thing still works fine, it lets out a little higher, but still works fine. I also never felt it slip once while I was torching it for hours trying to get the car out of the drift. I just think in that situation my clutch laster about two thousand times longer than if it was simulated in LFS.

I love the new shifting simulation in LFS.. it makes it way more realistic and fun to drive, but the clutch loses it's function (it slips), way way way too soon, especially when stopping and starting after a spin and whatnot.. Other than that it's a great patch.

before...



during...


after...


That was one scary 4 days w/o power.
#91 - JTbo
Maybe torque rating of clutch?

My IRL car had 160nm torque from factory, clutch can however handle 300nm of torque from engine, which means it can temporarily take lot more.
Quote from BigTime :The clutch just simply overheats too quickly. After a few spins or stops it begins to slip

Quote from danowat :I have noticed that under "normal" driving conditions, the clutch is fine, but if someone hits you in the behind, it heats the clutch up alot, also, if you spin off you tend to heat the clutch up alot too.

Yep, I've noticed the same.
I'll admit that I did spin a few times and had to drive away. As soon as I know I'm going to spin, I fully press the clutch. Driving away depends on what you want; harsh with a bit of wheelspin doesn't heat the clutch, smooth road car type launches do, a bit, but even then I drove away a few times with the clutch temp still in orange; never red!

I haven't been hit from behind yet, though I did notice the AI needs some tweaking in this regard..

Are we all playing the same sim??
During actual racing it seems fine, but if you do a quick couple of tests with the clutch to test how much it can take, it just goes to red instantly with any amount of intentional slippage. Then it quickly becomes unable to hold the power of the engine. At least in the new car.


Oh, I just tested the AI.. damn, they just ram you like you aren't even there... not even trying to pass. I thought they fixed that? I guess that must another thread.
Quote from tristancliffe :I managed to get a slipping FBM clutch to cool down whilst racing by only using 70% max throttle. Okay, I was 5 seconds a lap slower than usual, but it did eventually cool.

Having never had a hot, slipping clutch in real life, either in cars, bikes, trackdays, single seaters etc I still feel that something isn't right in that regard. But it does make races more... variable... just not very realistically.

The typical question would be: Do you shift IRL on trackdays like you do in LFS? Prolly with not lifting the throttle? As if you lift throttle correctly, it works fine, and there is basically no heat.
@ BWX

That sounds like a crappy time

As far as your clutch though.... Isn't the point that you were stuck with very little traction?

Not saying LFS's doesn't have problems with starts ( I think racing/driving is fine, and not sure how to rectifiy the starting issue ), but how long do you think that clutch would've lasted if you were rocking back & forth slipping the clutch for hours on pavement instead of snow?
#97 - JTbo
Quote from Ball Bearing Turbo :@ BWX

That sounds like a crappy time

As far as your clutch though.... Isn't the point that you were stuck with very little traction?

Not saying LFS's doesn't have problems with starts ( I think racing/driving is fine, and not sure how to rectifiy the starting issue ), but how long do you think that clutch would've lasted if you were rocking back & forth slipping the clutch for hours on pavement instead of snow?

I think he has possible fall on RPM trap, 3000rpm does not sound that bad in LFS, but you can't do same thing to clutch IRL as RPM feels too much.

If I try to start uphill at blackwood with similar rpm as I do with my IRL car(s) I end up jus stalling it even clutch bar moves that 1-2 pixels It needs 2-3krpm and we are at square one again.
Hm can we play the drivetrain flex card here?

From my playing around with the clutch ive come to the conclusion that it slips a lot more than I´d expect it to.
Shifting with just a small lift on the xfg reminds me a lot of the old fiat tempra my parents had. Both cars slip themself slowly into the correct rev match even if you let the clutch engage with a "digital" driver input.
Oh just for the record when driving quickly with the tempra I´ve never had any issues with the clutch (no smell, no noticeable degradation, no nothing) despite tons of slip on each shift.

Anyway point is that if you take your foot off the clutch pedal swiftly even when flatshifitng most cars I´ve driven don´t slip the clutch at all.
The result is usually a loud bang, a noticeable jolt going through the car and, presumably, engine mounts crying for mercy.

To get back to my original point, I think on a real car the engine mounts will take a lot of the stress from a quick change in engine revs instead of the clutch as it currently does in LFS.
#99 - JTbo
Quote from JTbo :I think he has possible fall on RPM trap, 3000rpm does not sound that bad in LFS, but you can't do same thing to clutch IRL as RPM feels too much.

If I try to start uphill at blackwood with similar rpm as I do with my IRL car(s) I end up jus stalling it even clutch bar moves that 1-2 pixels It needs 2-3krpm and we are at square one again.

I did manage to do this better now in X31, but I guess only me and my controls have changed meanwhile.

But still I need loads more throttle than IRL to keep it stalling, would be interesting to compare LFS vs IRL part throttle torque levels below 2000rpm :color: But still I think it can be my driving that sucks.

However that powershifting situation is a bit puzzling.

Anyway Scawen did mention in another thread that engine model + clutch do need work, but it is not going to happen to patch Y, so maybe we should just drive until patch Y is done

I need proper clutch and shifter
Very good point Shot.

Although even with that, the point is that the clutch is strong enough in most real cars, especially sporty ones, that you can jolt the car like that. The LX6 is really strange having so much slip.

Mounts should be really easy to simulate and would probably help the sim a lot. Can be hard for race cars and soft for road cars. All you need is basically a progressive spring model between the engine and trans so that the transfer is "buffered" by the spring. Would make for some very interesting results methinks, and not very hard to implement at all!

Clutch temp info
(106 posts, started )
FGED GREDG RDFGDR GSFDG