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darrob
04-04-2018, 06:13
So....

I cannot get my mind around the setup for tyres in wet conditions.
I've tried increasing pressures and some other stuff.
Basically I can never get operating temps into the tyres in wet conditions.
During private testing, the tyres just never get into the green and I feel like I'm driving on ice cubes.
It's really frustrating when driving an actual race. The tyres start a lovely green, but after a couple of laps I'm suddenly sliding all over the place.
Is there *any* way of turning off this feature. For me, it's taking the fun out of the game.

I'll be honest and say that the whole fiddling with adjustments is not my thing. It would be nice to have some basic setups available that are essentially "Here you go, this setup will make the car drivable in these conditions. Fine tuning can be done if you wish, but this setup will allow you to get around the track in one piece!"

Pekka Salminen
04-04-2018, 06:38
I haven't had such problems. In my understanding, wet tires are like softs; they are good when cold, but overheating is more of an issue. Maybe wrong pressures are the problem? Fiddling with brake ducts have big impact on tire pressures. My experiences are limited to GT3 and GTE cars, other classes might be different.

darrob
04-04-2018, 09:26
I haven't had such problems. In my understanding, wet tires are like softs; they are good when cold, but overheating is more of an issue. Maybe wrong pressures are the problem? Fiddling with brake ducts have big impact on tire pressures. My experiences are limited to GT3 and GTE cars, other classes might be different.

Hi

Thanks for the reply.
My understanding is that Cold tyres = no grip, regardless.

From what I can gather, wets are a softer compound. This is to help the car grip in the slippery conditions and to build up heat in the tyres.
My problem is that the tyres never heat up.
I can nose the car onto a wall and spin like mad for a while, and the rear tyres heat up. I then have grip for a couple of laps, then they go cold again and stay cold and I have no grip at all.

Been looking at some other posts on the subject of tyre temps, but they seem to be talking about dry weather and slicks. Nothing about wet weather so far :(

AbeWoz
04-04-2018, 10:56
what are the track temps you are running? its going to be hard to get temperature in your tires if its raining and 5C like it was at Oulton this past weekend for British GT.

Jordan_m6
04-04-2018, 10:57
Rain is a whole different monster. Being smooth is gonna be the hardest thing to control when you are racing. I have notice braking is not an issue in the rain with my driving style, but the desire to throw acceleration at the car during the turn while my tires are on the verge of breaking loose is what gets me everytime.

The big issue with this is that you cannot actually feel what the car wants to do. You can either tighten the cars steering or try to smooth your driving habits. The you can fine tune the car to gain speed in the correct places on the track. When and were you can add speed or knowing which corners you can push harder in the conditions correlate with drivability.

CastrolGT
04-04-2018, 11:20
in the wet, you have to lower the pressure. not only to get more contact surface, but also because the rain tyres have a lower optimal temperature. with a dry pressure, the wet tyres cannot get in temperature. so you'll have to lower the pressure to allow the tyres to work with flexibility and thus allowing them to heat faster and getting them in temperature. the higher pressure is used in hot race days to avoid the tyre to overheat easily. that's why in qualifications, you generally use more pressure than in the race. it's to be able to attack more without overheating. it makes the car slide easily when the tyres are cold, tho. and it will wear the tyre more easily. with a lower pressure, the tyre is less hard. allowing it to be more flexible. to work more. it creates heat. and more grip. that's why, if you look at dragster races, the tyres are almost flat. they are compressed. those tyres run very low pressure and needs to be a bit wet to start a burnout. and on the start, there's almost no wheelspin. try to do a dragrace with higher pressure on the tyres. you'll spin like hell because there's not enough flexibility of the tyres to give you more grip. so, in the wet and in cold weather, use low pressure :)

Bealdor
04-04-2018, 11:29
There's multiple things you can do to increase car handling in the wet.

- lower tire pressures, as castrol mentioned
- maximise aero (tires will be worked harder in faster corners which will increase temps)
- soften your suspension and ARBs for more mechanical grip
- increase ride height to compensate for the softer suspension and increased aero (and to not dip into the water with your underbody)

hkraft300
04-04-2018, 15:59
If you’re losing heat and pressure in your tires, you’re screwed.
Tune your tire pressures for the lower temperature running.
If you can’t keep heat in them, at least keep pressure up.
Close brake ducts and increase setup tire pressure will help.

darrob
04-04-2018, 16:08
what are the track temps you are running? its going to be hard to get temperature in your tires if its raining and 5C like it was at Oulton this past weekend for British GT.

Hi

Track is at 17C
The conditions are fog and rain, springtime at snetterton.
I'm trying the Lightweight KTM X-Bow
With the tyre pressure on initial setup at 1Bar, and the pits set to inflate to 1 bar, I cannot get the temps to above 18C at the front and 19C at the back.


There's multiple things you can do to increase car handling in the wet.

- lower tire pressures, as castrol mentioned
- maximise aero (tires will be worked harder in faster corners which will increase temps)
- soften your suspension and ARBs for more mechanical grip
- increase ride height to compensate for the softer suspension and increased aero (and to not dip into the water with your underbody)

As I said I've tried lowering pressure. I don't think that there's much in the way of aero on the KTM but I'll play with the suspension and ride height as well.

Thanks all for the replies :)

AbeWoz
04-04-2018, 16:18
17C is still bloody cold for a track, and with a light car like the X-Bow, you are bound to have some issues getting temperature into the tires.