No more flats, with Steve Peat. Preventing flats is as much about technique as it is about tech.
Your expert: Steve Peat
Steve Peat is the original OG of mtb. Born in Sheffield he raced (and won) pretty much everything going in DH, from World Cups in the 90s and Noughties to the World Champs in Camberra in 2009. Peaty is a true icon and has shaped the sport like few others.
Talent beats tech
Back when I started racing there was no tubeless sealant, no tyre inserts and definitely no dual-ply DH casing tyres – only inner tubes and even the best mountain bike tyres were thin (basically XC) tyres. So I’ve definitely learned a few tricks and techniques over the years.
The biggest part of avoiding flats is by improving your riding style. Once you know the trails, you can use better lines to go around the hard edges, avoid braking in the rough stuff and pick your landing spots for a smoother exit. Keep your head up and look far ahead on the trail too, it helps you spot sharp objects and stops you having to brake aggressively because you’re on the wrong line. This will not only help prevent flats but it’ll make you faster too. Smooth = no flats!
Choose your tyres wisely
Dual-ply tyres – or Kevlar-reinforced tyres – can really help because the tyre casing is so much stronger than single-wall tyres and really helps to prevent sharp objects puncturing through. Most brands offer varying levels of sidewall protection, with the most protection (and weight) designed for downhill or e-bike use, and the least protection and lowest weight for XC. As a general rule of thumb, go for more sidewall protection in the rear where you’re more likely to puncture.
Tubeless plus sealant
We have so much more tech to help to prevent flats these days and tubeless sealant, combined with tubeless tyres, has probably been the biggest game changer. Tubeless sealant is a thin (usually latex-based) liquid that creates an airtight seal between the tyre bead and rim wall so you can get rid of those heavy inner tubes. It’ll help you seat a tyre, then the residual liquid sealant left inside is flung to the outside when the wheel spins. This means if you do pierce the tyre, the pressurised sealant will squirt out and block the hole before much (if any) air escapes. Most of the time you won’t even realise you’ve punctured.
How to fix it
No two punctures are the same, so it’s still possible to get a puncture that doesn’t seal with tubeless sealant, and in spite of all of the above advice. Chances are it’ll be on the sidewall because punctures on the top of the tyre are more likely to seal themselves as that’s where the sealant gets flung to when the tyre spins. Most tyres only have dual-ply casing on the top of the tyres too, so the sidewall and the bead is the vulnerable spot.
You may need to use a tyre plug to get a reliable seal. Tyre plugs (aka bacon strips, aka dog poos) are super-sticky strips of rubber that are usually 1.5mm or 3mm thick – push one into a puncture using the small metal fork tool. This gives more structure to the hole and works together with tubeless sealant to achieve a reliable seal.
Pinch flats (aka snake bites) were the most common reason for punctures back in the day because we hardly had any suspension and sometimes we had to run pretty low tyre pressures to get grip in wet conditions. If we pumped our tyres up too hard in dry conditions we ran the risk of slices and cuts from scuffing rocks or even rolling over thorns.
Tyre pressure, then, is crucial for helping prevent flats. Run pressures too low and you’ll probably get a pinch flat or roll the tyre off the rim. Run the pressure too high and sharp rocks or thorns will more easily puncture the tyre, plus it’ll reduce your grip and comfort.
How do you get it spot on then? There’s no right answer because there are so many factors affecting the optimum pressure – how rocky or fast the trail is, the weight of you and the bike, the wheel size, your riding style and skill level, the tyres you’re running, and plenty more all determine the ideal pressure. The only answer is trial and error – buy a decent pressure gauge and start experimenting. Start at around 22psi in the front and 24psi in the rear and go from there.
Inserts can really help
Tyre inserts can be a great help to prevent pinch flats, especially when you’re still learning and find yourself casing jumps or piling into gnarly rock gardens heavy on the brakes on the wrong line. A tyre insert is a hoop of dense foam padding that sits inside the tyre, it’s job is to cushion the rim and stop it slicing into your tyre if you slam into a rock or root. Inserts also help to stop the tyre from rolling off the rim. This is because the insert pushes against the tyre bead and helps to keep it in place when running low pressures or shralpin’ turns.
“For the Santa Cruz Syndicate team set-up we use Peaty’s Tubeless Sealant, Peaty’s Rim Tape and Peaty’s MK2 Tubeless valves combo on Reserve carbon rims. I have also been fortunate enough to race and ride on Maxxis tyres for a very long time. With this set-up I don’t feel a need for rim inserts or anything similar.”
“Being a bigger guy, I probably run my tyres a little harder than most people out there. I can actually tell the difference when the tyres lose 1psi because I lean heavily on the edges of the tread in corners so the pressures are crucial for me. Just keep your head up, spot good lines and try to stay off the brakes in the rough stuff!”