My new T25 came running on a set of Borbet alloys 71/2J x 17 with 225/45R17 tyres all round. what should the tyre pressures be?
Does anyone know where I can get a wheelnut cover plate key from or alternative tool?
https://1drv.ms/f/s!Ag7PCj4gRrgFjRKlqN-rdHbo7Ibm" onclick="window.open(this.href);return false;
thanks in advance
steveh
Tyre pressures on Borbet Alloys and key tool
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Re: Tyre pressures on Borbet Alloys and key tool
With low profile/wide tyres best to buy a cheap IR thermometer (or a tyre pyrometer) and find out experimantally. There is no magic formula.
What you are looking for is an even temperature gradient across the tread i.e. the same temp all the way across or an even change between one edge, the middle and the other edge. This allows for wheel camber.
Start at 30psi, drive for 5 miles in the dry on a decent flat straight road and have an assistant ready to jump out and check one wheel at a time between runs iver the same stretch of road (take an average temp left vs right) because the tyres will cool off fast.
Ich fahre einen Bulli. Ich hilfe mir selbst...meistens!
What you are looking for is an even temperature gradient across the tread i.e. the same temp all the way across or an even change between one edge, the middle and the other edge. This allows for wheel camber.
Start at 30psi, drive for 5 miles in the dry on a decent flat straight road and have an assistant ready to jump out and check one wheel at a time between runs iver the same stretch of road (take an average temp left vs right) because the tyres will cool off fast.
Ich fahre einen Bulli. Ich hilfe mir selbst...meistens!
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Re: Tyre pressures on Borbet Alloys and key tool
I put my standard tyres on and it came up with a close enough value.
http://www.tyresafe.org/check-your-pres ... alculator/" onclick="window.open(this.href);return false;
http://www.tyresafe.org/check-your-pres ... alculator/" onclick="window.open(this.href);return false;
AGG 2.0L 8V. (Golf GTi MkIII)