Heat and Pressure
Fresh from IAM Observing yesterday I was reminded how vital it is that we know our tyre pressures and that we check them.
We always do a POWDERS check (see Blog post of 9 April) and that includes asking about tyre pressures, as part of the pre-ride briefing. Yesterday I was with a rider whom (like me) has the tyre pressure read-out on his bike dash display and that we can see as we ride along what the pressure is showing, using a sensor in each wheel.
I suggested that he makes sure he checks with a gauge, and always when the tyres are cold - don't only rely on the display.
The main reasons are:-
Tyres are designed to absorb heat and that affects the pressure when riding, so the hot pressure reading will be higher than when cold, meaning if you look at the display on your screen after riding for a while, that reading will be HIGHER;
The tyre pressure affects how the bike handles, grips and stops, therefore an over or under inflated tyre, when warm, will make controlling the bike more of a challenge;
Wrong tyre pressures cause the tyres to wear out faster
Tyres are what keeps us stuck to the tarmac and riding in dry warm weather, they will be sticky sooner, which we all want.
I check mine more often during warm conditions, as I find my tyres do deflate faster in warm riding, especially if the riding is "enthusiastic"...
For example, on the last rides in the Pyrenees my tyre pressures expanded by almost 15%! Plus my back tyre lost around 5% almost every other day.
I carry a small portable compressor which runs off the bike power source, which means I am always ready to top up, but please do check those tyres, now we have some warm riding weather; and use a gauge not only the dash display.