Tyre pressure on track

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phuk72
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Re: Tyre pressure on track

Post by phuk72 » Fri Feb 29, 2008 12:43 pm

Quan-Time wrote:[If you are asking the question, you probably aint the biggest racer in the pack. Thus, its a good place to start.

Normal riding on the road can provide upwards of 5psi on a nice warm day. So it will something you are familiar with. You can build from there.
Sorry if it sounded like a joke or a bit retarded, But for someone just starting to track ride, its a reasonable place to start.
OK - I see what you are saying.

personally, my advice is still to leave tyre pressures alone
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HansJ
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Re: Tyre pressure on track

Post by HansJ » Mon Apr 21, 2008 1:41 pm

Yup, I'm with phuk (and QT, in a way). Remeber, lowering the pressure means the tyre get warmer... It also depends on the track, at one track here in Sweden (Gotland Ring, known for wearing down tyres because of the surface), a (very fast) TRX rider found the Racetechs held much better with higher pressure, 2.3-2.4 bar. It also depends on what tyres You're running, both intended working temperature but how much hotter they'll run with lower pressure.
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Triton

Re: Tyre pressure on track

Post by Triton » Fri Jun 13, 2008 9:11 am

Just did a ride day at Eastern Creek last Sunday. A cool day which maxed out at 19 degrees C and track temperature well down. It rained briefly but heavily first thing and then cleared enough for the track to be 95% dry by 11.00am.

I used a 120/70 Diablo Corsa front and a 170/60 Evo SC2 (medium compound) rear - John M also has one of these which were a special tyre brought in for Buell X1 Lightnings for racing in the now defunct ARRC Naked Lights series and they ARE sticky. I also used Bandit tyre warmers and this time out had a tyre temp probe (ex-Klaffi Honda WSBK team, thanks guys).

I sat out the second session after almost binning it in the first - the back was absolutely f'in 'orrid in the wet! So the old girl got over an hour and a half on the race stands with warmers. The rider got three coffees and half a pack of Arrowroot bikkies!

Pre-session temps/pressures were: F 82/34, R 84/32. After a good fang and average 1:47 lap times (yeah, yeah I know, Criville's lap record is a 1:30, but there were still a few damp patches and lots of muggles) the temps were: F 86/36, R 93/38. Just thought it was interesting and I've no real idea if these are normal in "proper racing" but it's interesting that the back increased pressure much more than the front, yet looks like it had hardly done any work - no cold tearing, just a smooth consistent roughness right to the edges. Anyone know why? I ask because I am not a rear end hero, sideways action is not my domain. :oops:

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