£400 for a set of 'free' valve caps
Discussion
got a set of lovely porsche crested metal valve caps free when i purchased a pair of seat belt pads off ebay recently.
they looked very smart and promptly put them on my car.
at vmax on sunday my rear offside tyre loses all pressure and the cause is down to a hole in the valve stem rubbing hard against the alloy.
as a result the tyre runs flat and the inside wall of said tyre rubs on itself and wears down to the threads, thereby making the tyre dangerous and therefore needing to be replaced.
on closer inspection of the remaining 3 valve stems, i notice they all show sgns of wear against the alloy... why should this be i wonder.... basically the lovely shiny porsche crested valve caps although being light are 'top heavy' and the centrifugal force created when the wheels turn at high speed have caused the valve stems to bend over and rub constantly against the alloy, so much so that not only has it rubbed a hole into itself, but on one of the wheels it has damaged the alloy where the stem has rubbed so hard that the top layer of glaze or whatever it is on the alloy has completely rubbed off.
bottom line however is that two new rear tyres are required. cost to you sir... £400.
motto (as if you didn't know)... nothing in this life for free. and don't try and be flash - keep the plastic valve caps.
they looked very smart and promptly put them on my car.
at vmax on sunday my rear offside tyre loses all pressure and the cause is down to a hole in the valve stem rubbing hard against the alloy.
as a result the tyre runs flat and the inside wall of said tyre rubs on itself and wears down to the threads, thereby making the tyre dangerous and therefore needing to be replaced.
on closer inspection of the remaining 3 valve stems, i notice they all show sgns of wear against the alloy... why should this be i wonder.... basically the lovely shiny porsche crested valve caps although being light are 'top heavy' and the centrifugal force created when the wheels turn at high speed have caused the valve stems to bend over and rub constantly against the alloy, so much so that not only has it rubbed a hole into itself, but on one of the wheels it has damaged the alloy where the stem has rubbed so hard that the top layer of glaze or whatever it is on the alloy has completely rubbed off.
bottom line however is that two new rear tyres are required. cost to you sir... £400.
motto (as if you didn't know)... nothing in this life for free. and don't try and be flash - keep the plastic valve caps.
Early 911 s and Turbo 924 etc used to run small self adhesive supports stuck on the rims, especially wide ones , to hold longer valves straight against the centrifugal force ........rubber valves come in 3 lengths ..at least ,sorry, bit late i know but the shortest ones wont cause this prob.
I had the metal supports on a previous 3.2. For track days I always run metal valves which are effectively screwed tight. They are about a fiver each, do not move and don't look too bad.
I hope the tyre sidewall is fine now you have some decent pressure in, it didn't seem too bad and difficult to justify scrapping the tyre.
I hope the tyre sidewall is fine now you have some decent pressure in, it didn't seem too bad and difficult to justify scrapping the tyre.
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