Tyre Pressure

[evotell]

Last year I put a post on Blatchat regarding running CSR rear rims on an SV.

 

We have played around a lot with the geometry and made some huge changes. However we are at odds regarding rear tyre pressures. The CSR runs with I believe its 22 lbs however we have found that way too hard and at present are running 16lbs.

 

Any thoughts or opinions would be much appreciated.

 

Terry

 

Caterham SV 1400 Hayabusa

WHEN QUICK JUST ISN'T FAST ENOUGH!.

 

www.my7.ca

 

Edited by - evotell on 7 May 2008 18:06:19

[brianmurray325hotmail.com]

you got csr wheels to fit your SV without fouling anything?

c7 bmu

[tricky dicky]

We have played around a lot with the geometry and made some huge changes- says it all really

[barong77]

i fitted csr wheels to my sv and all i had to do was fit the longer caterham wheel studs and fit 5mm wheel spaces, this allows plenty of room for any tyre deflection at speed, i have run like this at a number of track days and so far had no problems, other than oil surge as with the bigger boots and no dry sump its i suppose similar to running slicks maybe . it do look good though .

[6speedmanual]

Hi Terry

 

How's life in Red Deer? Long time since the post 50 Years of the 7 sauna!

 

Low pressures like 16psi sound ok to me for cold. As the tyres fitted are wider with greater ground contact patch, I understand part of the equation is that they need less psi to support the weight of the car static. There are other considerations of course, such as flatness of tyre across contact patch, how much deflection is influenced by pressure and whether ride issues (bounce frequency) affects grip on bumpy corners

 

What pressure do they rise to when warm/hot?

 

On my CR500 205 section rears, running 22 psi hot on dry trackdays. Usually set to 18psi cold then check and set after first 20 minute session.

 

Wet/cold days, I start with 18 but they tend not to go over 20 as can't get enough warmth into them.

 

CR500 is a tricky customer sub 10degCelcius! 😳

 

cheers

Peter

 

 

6SpeedManual

*tongue*There's no such thing as too much BHP per Ton 😬

[Rowland Cook]

Was on a curborough outing with the LADS crowd with my new 8" rears and 6" fronts and was messing with tyre pressures.

 

It rained and I span off into the centre and drove quietly back and parked up and went for calming tea in the rest tent.

 

After a minute or two I could clearly see that there was a strip down the middle of the rear tyres that had dried out and also down each side of the front tyres.

 

So I dropped pressure at the rear (running on the centres) and pumped up the fronts (running on the edges). Finished up with 16 psi rear and 20 psi front as optimum.

 

No wonder I span out. I think you've got it about right.

 

Regards

Rowland