sorens2
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| posted on 3/9/09 at 09:06 PM |
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Tyres not warm enough... Why ?
My Toyo R888 wonīt come over 40-45 deg C at trackdays.
20 PSI
MNR VortX ZX12
Laptimes are ok but should be better if tyres would warm up.
Weather is 25 deg C.
Is my driving skills really that bad ?
http://www.youtube.com/watch?v=Py492-hxLh8
Soren S2
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dan__wright
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| posted on 3/9/09 at 09:07 PM |
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20psi seems pretty high, im running about 16
FREE THE ROADSTER ONE
!!
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Dangle_kt
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| posted on 3/9/09 at 09:27 PM |
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yeah, your rubbish! 
Now stop pretending your slow, and admit your showing off! 
Do you feel you are spinning up, or loosing grip on the front? Under braking or in the corners? turn in or on the power out? I'm curious why you
think there is a problem, as you look pretty smooth.
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coozer
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| posted on 3/9/09 at 09:56 PM |
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I have 14psi in mine and they get warm to the touch but nowhere near 45 degrees..
I would suggest more power, faster driving may get them warmer..
Have you seen the bird who rips round faster than everyone else in a transit van??
[Edited on 3/9/09 by coozer]
1972 V8 Jago
1980 Z750
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sorens2
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| posted on 4/9/09 at 05:18 AM |
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Sabine Schmitz. Seen her in person. Nice girl.
I just know that the R888 should be between 85 and 95 deg C.
There they have grip.
I canīt brake late enough.
I canīt corner fast enough.
I canīt go on the throttle early enough.
I canīt figure it out.
Soren S2
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jeffw
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| posted on 4/9/09 at 05:36 AM |
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Certainly dropping the pressure will improve the situation. What was the track temperature when you measure your tyre temperature ?
The only comment on your driving I would make is you need to learn to heel and toe on the downshift, sounds painful in a BEC.
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smart51
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| posted on 4/9/09 at 07:07 AM |
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I can't speak for R888 but I tested tyre pressures in Proxes T1S (or T1R I can't remember) in my R1 VortX at Mallory Park. I started off
at 16 PSI all round and went up in 1/2 PSI steps. Each 1/2 PSI gave me about 2 more MPH round Gerrards - the long fast corner at Mallory. At low
pressures the car was wobbly on turn in and a bit edgy in steady state cornering. Higher pressures (19 - 20 PSI) felt much more solid and in control.
Each seven is different but 16 PSI is very very low.
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progers
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| posted on 4/9/09 at 07:35 AM |
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Hi Soren,
You don't mention whether the tyres are 20psi hot or cold. If when you come in the pressure is 20psi, then you may want to put 1-2psi more in
the tyres. I run yokohama 048's in a race series in the UK and they like to be around 21-22psi hot (i.e. on track). I set them to 21psi when I
come in from a run.
Regarding temps, it hard to measure how hot the tyres are on track, by the time you circulate round the track on a slow down lap and come in, the temp
will fall off considerably. Its just as important that you are getting even temp across the tyre (maximises grip). You can optimise this my changing
wheel camber (more negative camber will help inside of wheel warm up, if centre is cool it indicates too low tyre pressure).
Regarding driving your lines look good, it looks to me as though you could carry more speed through the corners with a bit of trail braking and
getting the car to drift a little bit more. The circuit is very tight with not very high speed corners, this will make getting tyres upto temp more
difficult (there is nothing like a drifting round a 100mph corner to get your tyres warm...)
Last thing to mention of course is suspension setup. You need to have a good balance so that you can confidently operate at or near the limit of
adhesion with confidence. Your car looked a little understeery, which you can dial out with some suspension tweaks (soften front suspension/stiffen
rear suspension/raise rear ride height/increase front camber). Its upto you to figure out which way works best - thats the fun of these cars :-)
Hope that helps
Paul
[Edited on 4/9/09 by progers]
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turboben
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| posted on 4/9/09 at 12:11 PM |
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What size are they?
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Frosty
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| posted on 26/10/09 at 09:53 AM |
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The important things here are:
1) Tyre pressures - is 20psi hot or cold?
2) Tyre sizes? What are tyre sizes both front and rear.
These two facts will give us a much better idea what is going.
Also, how are you measuring the tyre temperatures? Are you looking at surface temperature, or core?
A probe type pyrometer will give you the true story. An infrared gun will only give you the surface temperature of the tyre, which by the time you
have measured it will not be very accurate.
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