Jeff Wiltshire

I'm off to Brands on Wednesday 29th for a Tracksense trackday and wondered what tyre pressures people run on either normal road tyres or slicks.

Cheers


Jeff

JohnS

iTrader: (1)

Road tyres - use anything from 36psi upwards (some people go as high as 50psi!). This stops the tyres rolling onto the sidewall, and scrubbing off the shoulders. Best bet is to find some settings which suit your driving style.

Slicks - these use a different construction from most road tyres, and I think most people use pressures around 26 - 28psi to get the best results.

Jeff Wiltshire

Thanks John....

50 psi seems a mite high (images of exploding tyres) 36 sounds about right.

Interesting about the slicks needing less pressure.... I would have assumed in my ignorance the other way round, just as well I checked !


Cheers

TimK

Road tyres : 40psi front, 38psi rear

Slicks : start with 32psi front, 30psi rear. Then monitor closely throught the day.

Works for me

Cheers,
Tim

Stuart Knight

iTrader: (2)

Road tyres: use around 35psi give or take a pound or two, but check them after the first session, they will have gone up by up to 10 psi. let them back down to the starting pressure. Check again after the second session etc. You may find the left hand tyres (especially front) go up again, but they should stabilise after a couple of sessions.

Slicks, I use 26 in the cold/damp, 28-29 when its warmer. Use the same method as above for adjusting the tyre pressures after each session.

Stephen Read

Jeff,

I'm bored today so heres a long reply...

We all know that we should set tyre pressures cold - because they can rise due to friction and heat soak (from the brakes etc.) when in use.

On a dry or drying track, I have found they can rise by over 10psi per corner, so if you start of with 36 cold, you will be over 40 before you know it.

This can lead to increased wear in the centre of the tyre but as JohnS said, it will protect the outside shoulders a little.

Solution:

Set them cold,

Buy a guage,

Check them after each session,

Be prepared to release air to keep the pressures from creeping up to high,

Remember that if you have let air out during the day you should boost them before you drive home as a long motorway drive on reduced pressures will not do them any good either.

I have read that F1 tyres are inflated to less than half what we normally use on the road and they use pyrometers to measure the temperature across the tread while testing.

If the middle is hotter than the outside edges, they drop them slightly as the best performance will be obtained when the load is shared right across the 'contact patch'.

On the road, I run standard settings (rears slightly lower than the fronts) which gives me more comfort and grip (softer sidewalls, bigger contact patch).

On the track, I try to make it a little more 'tail happy' by raising the rears.

On my first dry trackday, I recon I lost the top 3mm from a virtually new set of OEM tyres. The next (dry) one was at the RSOC day at Silverstone in July and I decided to rent a set of partworns to avoid killing the remaining 4mm. However, when I handed them back they were still in pretty good shape.

My assumption is that if you start of with new tyres on a dry track day be prepared for significant wear (if your having fun). If they are already half worn the wear will be far less noticeable.

That's what I hope anyway! PS. I'm doing Snetterton on Sunday an might pop down to Brands for a look on Wednesday.

phil_ng

Jeff, Obviously depends on track conditions but I suggest you try to get to 45 all round hot. Last week at Donington slightly damp and cold starting off at 40 cold ended up about 45 hot. This was on 3/4 worn Toyos. Another guy there in a uk Impreza killed his sidewalls running standard pressures - tyres virtually scrap after 10 laps. Mind you he seemed to complete half each lap on the grass.

Phil

AlexM

Hi,

May I draw your attention to this: