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Strange car behaviour #257

Closed Pawks666 closed 8 years ago

Pawks666 commented 8 years ago

I experienced a problem on skidpad 3, circuit track. Sometimes car just becomes uncontrollable...on times it goes reverse in forward gears, other times it just wanders off even flying through the air, engine revs very high with none gas applied - strange stuff in general. I haven't been able to figure out a pattern which triggers this, but I think that this only happens when tarmac tires are used in setup. At least i didn't notice this happening with gravel tires.

lucatabaton commented 8 years ago

I experienced the same. It looks like tires suddenly loose any kind of grip and/or friction. Infact if I brake it stops at least revving. It's strange as starting the stage for few corners it's normally working fine.

paskalip commented 8 years ago

Had the same issue in skidpad when I crashed in the invisible barrier that blocks the entrance to disabled areas. The car went into reverse no matter the gear and kept accelerating.

ghiboz commented 8 years ago

where is the point that happens this?

IronFly74 commented 8 years ago

i can replicate it on skipad using keyboard, without touching any wall.

just accelerate until you can engage the 4th gear, around 100km/h, keep it steered to the center of skipad, lift the throttle just to manage a little the understeer, accelerate again. the car will start to slide without any control and it will start to accelerate on its own.

you can even put to neutral and the car will still run back and forward, if you pull the handbrake, you will notice that the front wheels are running like the car was a TA or 4WD. check replay: https://drive.google.com/file/d/0By4gMxBMR6uiTU5PYlpnOHgzZFE/view?usp=sharing

Pawks666 commented 8 years ago

another example: https://drive.google.com/file/d/0Bw53RWSU8dfYOHVhdkxza3pvTUU/view?usp=sharing starts at around 2:20 onwards.

ghiboz commented 8 years ago

please try with the tyre window (F1) open and check if this strange behaviour happens when the pressure/temperature comes to a high value

IronFly74 commented 8 years ago

The issue arises when tyre pressure goes over 1.99 bar, at 2.00 the car start to slide and front wheels start to have traction as was 4WD. i managed to stop completly the car, no gear, brakes and handbrake on and noticed that temperature dropped very slowly (@0.01 rate) but pressure never went under 1.99.

temp

szdeak commented 8 years ago

Looking at the values in the picture, I have a feeling that the 134 bar pressure (and 10789 degrees) of the front right signals the issue better than "going over 2 bar" :D

IronFly74 commented 8 years ago

ahhaha yep that was the worst case, but you will face the car slide just passing the 2.00 bar pressure.

IronFly74 commented 8 years ago

yes, i confirm, it's pressure related. on setup screen, put 2,20 as pressure and enjoy the crazy 131 only on tarmac tyres!!!!