Tires and air occupy a lot of cyclists’ time when they’re getting their ride set up. Just like all things bicycle, there’s a serious learning curve for seemingly simple things. Tire inflation is something that a newbie needs to learn, otherwise, they’ll find out the hard way.
How hard should bike tires feel?
Most bicycle tires should feel firm-to-hard when they’re at the right pressure. However, proper pressure (and firmness) varies between bike types, so feel is not a very accurate indicator. But, as a general rule, road bike tires should be quite hard and mountain bike tires will be firm, but with a little more “give”.
Tire pressures are a complicated matter, and just judging by squeezing the tire isn’t the best way to do things. The truth is that you need to ask the right questions, and to that end we’ll answer the following for you:
Should Bike Tires Be Hard?
How hard your bike tire is will depend on the type of bike you’re riding. In general, off-road capable bikes should be less hard than those which are intended only for road use but it depends on a wide number of factors.
Should Road Bike Tires Be Hard?
A typical road bike tire is held at a very high PSI compared to other types of tire. Due to that simple fact they’ll often feel very hard if you poke or squeeze them, especially when compared to bikes that are intended to go off-road.
Should Mountain Bike Tires Be Hard?
Mountain bikes often change their tire pressures depending on what type of riding is being done. In any case, they’ll never be quite as hard as road tires but they’ll usually still be very firm to the touch. They may feel a bit soft when at the bottom ranges of acceptable pressure for riding off-road.
Should Hybrid Bike Tires Be Hard?
Hybrid bikes often straddle the line between on-road and off-road pressures. Sitting firmly in the middle, they’ll usually feel hard to the touch when in the top end of their range but at minimum, they should be very firm.
How Much Air Pressure Do Bike Tires Need?
The best way to figure out the PSI your tire requires is to take a look at the sidewall. You’ll find the range there and that will make a solid, safe starting point to start finding the pressure you like on your bike.
For those curious, keep reading and we’ll go over the typical PSI ranges for the various types of bicycle. You can also find a calculator online, since rider weight can affect the optimal pressure.
Typical PSI Range for Road Bikes
Road bikes run the highest pressures, usually ranging from 85-110 PSI. This leads to a hard that grips the road well and most roadies will experiment with the pressure until they find the right fit for their riding style and area.
Road tires run at much higher pressures than other types of bike tires. 110 PSI is a lot of pressure, your car’s tires usually top out at around 45 PSI. The high pressure works great on long, smooth areas where you aren’t likely to encounter obstacles.
Lower pressure can help if you’re riding on rougher roads or hard-packed dirt. The high pressure of road tires can make hitting obstacles a bit jarring.
Typical PSI Range for Mountain Bikes
Mountain bike tires generally run 30 PSI when riding trails or off-road. If you choose to use the bike on the road, then 40-50 PSI is about right. Normal mountain bike tires will work fine in either range.
Mountain bikers who also ride on the road will have to change pressures most of the time. The 30 PSI which allows awesome grip and obstacle handling on trails also lead to a slower bike that requires more effort on the road.
That said, 30 PSI is rideable on the road and it’s not necessary to change the pressure for a quick ride to the store.
Typical PSI Range for Hybrid Bikes
Hybrid bikes straddle the area between road bikes and mountain bikes, and the pressure in the tires shows it. The tires typically run from 50-70 PSI, while also straddling the width between road bike and mountain bike tires.
Hybrid bikes occupy a niche in between dedicated mountain bikes and road bikes. The tires are wider than road tires, allowing them better handling off-road and reducing the required amount of pressure to get a good ride.
Running on the lower side is a good idea if you’re primarily riding trails, but the higher side may be better if you’re riding on roads in good condition.
How to Check Bike Tire Pressure (Without a Pressure Gauge)
Tire gauges are great, but you may not have one lying around.
If that’s the case, then there are a few ways to get a general overview of your tires’ readiness to ride. Once again it depends on your bike’s style:
- Road Bikes-Squeeze the sidewalls together. At the proper pressure, you should have trouble squeezing the tires at all.
- Mountain Bike- Sit on the bike and take a look at the tires. For proper off-road riding, they should protrude a millimeter or so on the sides, but anything further than that means they’re underinflated. For road riding just make sure there’s a tiny bit of give left and don’t spend too long at the pump.
- Hybrid Bike- A hybrid bike should have just a touch of give when you poke down on the tire and squeeze inwards a little bit if you pinch the sidewalls.
You should still check with a gauge at the first opportunity. Most gas stations have tire pressure gauges attached to their air pumps if you don’t have one at home but the above guidelines will be enough to get you home at the very least.
Always err on the side of caution if you feel like you’re overinflating a tire.
What Happens If You Over-Inflate Bike Tires?
If you overfill your tires you’re in for a hard ride. Tires filled too much tend to “bounce” more on obstacles and you’ll feel a lot more vibration than normal.
In more serious cases the tube can protrude from the rim and pop, or the tire can be permanently stretched and made useless. If the tire’s bead holds, you may even witness explosive decompression.
Few people will pump air into a tire until it fails completely. Most of the time you’re just in for a bad ride. Hard tires lead to a lot of vibration and really don’t help if you hit any obstacles.
Of course, once in a while, someone feels the need to push it.
Can Bike Tires Explode?
In some rare circumstances, tires can have a catastrophic failure that results in explosive decompression. It’s not a common occurrence, but it does happen if a tire is seriously overinflated.
Explosive decompression can cause injury to the rider, or even just the person pumping up the tire. If you want to learn more, check out our article about why tires explode and how to avoid it.
What Happens If You Under-Inflate Bike Tires?
Underinflated tires have a lot of rolling resistance, leading to a slower ride that can feel sloggy. You may also run into problems with pinch flats and hitting obstacles too hard can cause damage to your rims. In general, you’ll be slower, and your bike will be more vulnerable to damage.
Few people underinflate their tires when they’re working without a gauge, but it does happen. Slow leaks can also cause underinflation at inconvenient times.
As a general rule, you’re just going to be slower with an underinflated tire. In severe cases, you may damage the rim on obstacles, since there’s less protective air cushion in between the rim and whatever you hit.
The increased rolling resistance will noticeably affect your ride in most cases. If your bike seems to take a lot more effort to pedal than normal, the first thing you should take a look at is the tires.
Read our article on wether you can ride a bike with a flat tire to learn more.
How Should Bike Tires Look When Riding?
Your tires should look almost the same when you’re on the bike, with just a little bit of give to the sides with your weight all the way on the bike. If they look drastically different or don’t give at all, you most likely have the wrong pressure in your tires.
Occasionally a new rider will notice that their tires seem to be bottomed out when they’re actually on the bike, although they felt fine in the first place. This happens with larger riders especially.
In most cases, it’s just a matter of underinflation for their size. A bigger rider may need higher pressures, but the most common culprit is checking the pressure by hand and just assuming it’s good despite the evidence to the contrary.
Tires can also look a bit odd while riding to new cyclists while they’re riding. You’ll get used to it, as long as the pressures are okay you’ll be great!
If in doubt, check the pressure.
