Repair notes
Getting Tyre Pressure Right for Your Weight and Your Tyres
I spent years running my tyres at whatever pressure was printed on the sidewall, wondering why some rides felt harsh or why I was getting pinch flats on perfectly decent roads. Turns out that maximum pressure stamped on your tyre is just that—a maximum, not a recommendation. Getting tyre pressure right for your actual weight and riding conditions makes a massive difference to comfort and control, and it's something I wish I'd figured out earlier. Here's what I've learned from plenty of trial and error in my cold garage.
Why the Sidewall Number Isn't Gospel
Every tyre has a maximum pressure rating moulded into the sidewall, usually something like 65 PSI or 120 PSI depending on the tyre type. For ages I thought that was what I should be running, but that number is just the structural limit of the tyre casing—the point where the manufacturer says it won't fail. It's not optimised for your weight, your bike, or how you ride. A 55kg rider and a 95kg rider on identical tyres need completely different pressures. I weigh about 82kg with my kit on, and I was massively over-inflating my 28mm road tyres by just following the sidewall. The ride was harsh, I was bouncing over imperfections rather than rolling over them, and honestly my grip in corners wasn't great either. Once I started experimenting with lower pressures based on actual guidelines, everything improved.
Starting Points Based on Tyre Width and Rider Weight
There are proper calculators online now that factor in your weight, tyre width, and even weight distribution between wheels, but I've found some basic starting points work well for initial testing. For road tyres around 25-28mm wide, I start around 70-80 PSI for my weight. When I had 32mm tyres on my hybrid, I was down around 55-65 PSI. My mountain bike with 2.3 inch tyres runs best around 25-30 PSI depending on terrain. The heavier you are, the more pressure you need to prevent the tyre compressing too much and risking pinch flats against the rim. The wider the tyre, the lower you can go because there's more air volume supporting your weight. I keep a little notebook in the garage where I've written down what works for each bike and tyre combination, because I absolutely cannot remember these numbers otherwise when I'm standing there with a cold pump in February.
Testing and Adjusting From Your Baseline
Once you've got a starting pressure, you need to actually ride and pay attention to how it feels. I do a loop around my neighbourhood that includes some rough tarmac, a smooth section, and a few corners. If the bike feels skittish or harsh, or I'm bouncing on rough surfaces, the pressure is probably too high. If the tyres feel sluggish or I can feel the rim bottoming out on bumps, it's too low. I adjust in 5 PSI increments for road tyres, maybe 2-3 PSI for mountain bike tyres where the pressures are lower anyway. It takes a few rides to dial it in properly. I also check pressure before every ride now because tyres lose pressure over time—butyl tubes lose maybe 5-10 PSI per week just sitting there, and if you've gone tubeless like I did on one bike, you need to check even more often. A floor pump with a reliable gauge is essential. Those little frame pumps are lifesavers for roadside emergencies but useless for accurate pressure setting.
Conditions and Terrain Matter More Than I Expected
I used to set pressure once and forget about it, but I've learned that adjusting for conditions makes a real difference. When I'm riding on wet roads, I drop pressure by about 5 PSI because the lower pressure gives me a bigger contact patch and better grip, which I need when things are slippery. On my mountain bike, trail conditions change everything—hardpack dirt I'll run closer to 30 PSI, but if it's muddy or loose I'll drop to 24-25 PSI for more traction. If I'm carrying extra weight like panniers for a longer ride, I add about 5 PSI to account for the extra load. None of this has to be complicated or precise to the decimal point, but paying attention and making small adjustments has eliminated most of my pinch flats and made rides noticeably more comfortable. Your tyres are the only contact point with the ground, so it's worth spending ten minutes getting the pressure right rather than just blasting them up to whatever and hoping for the best.
Questions people ask me
Can I damage my rims by running lower tyre pressure?
You can if you go too low and get pinch flats where the tyre compresses fully and the tube gets pinched between the rim and the road. This is why you still need adequate pressure for your weight. I've found that staying within reasonable ranges based on tyre width prevents this—I've never damaged a rim from proper pressure, only from running things too low or hitting obstacles too hard. If you're running tubeless, you can generally go a bit lower safely since there's no tube to pinch.
Do I need different pressure in front and rear tyres?
Yes, usually. Most of your weight is over the rear wheel, especially if you're carrying anything. I run about 5-10 PSI less in my front tyre than the rear on my road bike. The front tyre does most of your steering and braking, so slightly lower pressure there gives better grip and comfort without much downside. On my mountain bike the difference is smaller, maybe 2-3 PSI. It's another thing to experiment with, but rear slightly higher than front is a sensible default.
How do I know if my pump gauge is accurate?
Honestly, most cheap gauges aren't very accurate, but consistency matters more than absolute accuracy. I tested my floor pump against a separate digital gauge I borrowed and found mine reads about 3 PSI high, so I just account for that. If you're getting good performance and no flats, your gauge is probably fine. What matters is using the same gauge consistently so your adjustments are relative to a known baseline. If you're having persistent problems or racing where watts matter, investing in a proper digital gauge might be worth it, but for general riding, a decent floor pump gauge is adequate.