When I first started riding mountain bikes I was lucky enough to have Tris Kerns look after my bikes. Tris, who was Jill Kintner’s (Queen of Crankworx) mechanic and travelled the world, knows a fair bit about bikes. One of the most important things I learned from Tris was the importance of tyre pressures, and a couple of ways to work out how to set them.The thing I remember most was that tyre pressures should not be run really low to get more grip, as that is the job of properly tuned suspension. Taking the time to make sure you are running the correct tyre tread and compound will help with grip, but the important thing about tyre pressure is to make sure you finish the ride or race, and it should be set to compliment the tread pattern, rubber compound, terrain, rider weight and riding style.
There are so many people running crazy low pressures like 18 psi on all sorts of surfaces, like hard, rocky surfaces, trying to get grip when they should really be looking at setting up and tuning their suspension to get grip or making sure that the tyre being used is correct for the riding conditions. Running these low pressures, especially on rocky trails, just increases the chance of you getting a puncture when the tyre deforms, or damaging rims because the side walls don’t have enough support when you hit rocks or have bad landings. Using super gravity or double down tyres can help this, but that is way more expensive and heavier, and can be avoided.
When we first decided what pressures to run for my weight and riding style, Tris taught me to run high pressures when I first set up my suspension on an intermediate trail using the tyre tread and compound suited to the trail. Once I had found that sweet spot for keeping traction, I started to reduce my tyre pressures, 1 psi at a time, keeping the suspension working the same. Once I started to notice a change in how my bike felt with things, like tyre squirm or maybe slowing down when pedalling due to tyre drag, I recognised that I had probably gone too low and I would put some air back in. Even 1 or 2 psi made such a huge difference to how the bike rides.
I did this and found the tyre pressure that worked best for me, and I do this test sometimes when I change suspension, for exampled from air to coil, or change tyre brands. It won’t necessarily work for everyone, but it worked well for me and it is advice I have always appreciated.
By Sam Luff - Pushys Sponsored Rider