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Even the website that Paul Young suggests estimates 32 psi for a rear tyre using FOUR cylinders.
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You can't get 32psi from using the standard bike air cartridges - no matter how many you attempt to put in/use, after 2 and a half cylinders the pressure in the tyre will equal the pressure in the cylinders so will not inflate any higher.

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This is less than the one up pressure specification of a GS and almost low enough to be illegal.
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I didn't think there was such a thing as an illegal tyre pressure
If you want to lower your pressure to go of raod or to suit the conditions thats down to you. How can a law decide that for you


