What is a safe/practical amount of pressure to drop from a tyre like the Distanzia. .? I often take the short cut home down Chalkpit lane. ..it's a mixture of chalk and flint and lots of loose shingle for the last half mile. All the gullys and washout are no problem...but the loose stuff has the Tenere all over the place! , I've never dropped tyre pressure before so no nothing about it. .....Steve