How much air pressure should I put in my tires?

Question

I'm a first time cyclist and I need some good advice on how much air I need in my tires for my mountain bike. My tires say 50psi but even my tire gauge for my car doesn't go that high. Little background info: I'm about 225lbs, 6ft tall and plan on riding it to work (mostly streets, some dirt) about 10miles one way.

Thanks in advance.

Answer 1

You should definitely go up to the max rated pressure at your size. If you plan on commuting, invest in a floor pump with a guage, you can usually get a decent one for less than $50, and if you take care of it, it will last ten years easily.

Also, think about a smooth high pressure tire. They can handle smooth dirt roads, and you can pump them up higher so it's alot less work.

Answer 2

Your tire sidewall should actually show TWO values for air pressure. One is the lower 'safe' region, primarily used for dirt/mud riding and is typically 40 psi (2.7 bar = 276 kPa); the other is the upper 'safe' region', primarily used for hard surface - like roads - riding and is typically 65 psi (4.5 bar = 448 kPa).

Being a relatively big guy and having mostly hard surfaces to cover, I'd put your pressure around the midpoint of the range ... say 50-54 psi (3.4-3.7 bar = 345-372 kPa). This is because you're going to need a little more 'give' to the tire as a cushion, and any bump you take will further stress your sidewall and tube.

If you're planning on riding fairly regularly - and definitely, if it will be frequently - invest in a good bike pump with a dial-type pressure gage as part fo the pump. These are often 'foot pumps' ... so called because you stand on small tabs at the bottom to steady it while you pump. A reasonably good one will run you about US$30. Just check it works for the valve type used on your tube (either a Presta or Schrader)!

And besides ... you can always use the same pump to top up the pressure in your car tires, provided it has a Schrader option.

Answer 3

A lot depends upon the type of tyre that you have. Car tyres are thicker, especially on the side walls. This means that you can run with lower pressures. Tubeless tyres also have the different pressure requirements.

The optimum psi for a mountain bike that does a road and XC is 45psi. The less pressure that you have, the plusher your ride, but this increases the chance of a pinch flat. Higher pressure means higher speed, less chance of a pinch flat, but a rougher ride.

I run at about 60 psi, but some race riders go higher to 70. Because you are looking at mostly road, I would consider about 55 +. You might also look at fitting road tyres, this could increase your speed by a considerable margin, although if the dirt is XC, rather than trail, this might not be best.

Luck

Answer 4

I am 5'4" about 240 lbs. and also have a mountain bike. I keep mine between 52 and 54 pounds for on road and check periodically to make sure the tires have enough air. My small pump that plugs in goes to about 200 psi. We have used it to fill the car tire. Over the past 30 years I've ridden the mountain bike on both dirt and gravel roads and trails. One year I rode it over 300 miles just on short 5-10 mile rides around home as well as going on some 20 mile rides on bike trails. Had the bike trail near our house been completed 20 yrs ago my husband would have ridden his bike to work. (10 miles) We're retiring this year and are going to enjoy the trail.

Answer 5

You can get bicycle (and other high-pressure) tire gauges at most bike shops which will go up a good bit higher than your car tire gauge. Otherwise, if you get a good bicycle tire pump, it will tell you the pressure. You'll want to keep your pressure on the higher side of 50 to prevent pinch flats, which means you'll want to keep check your pressure at least once a week or every time you go out if it's less frequent than that.
Good luck, and don't get discouraged with the commuting. It's totally worth it.

Answer 6

All good answers, let me add one thing. Remembe when you ckeck the air pressure in your tires you will lose a little bit each time. Had a customer who checked weekly...and her tires kept losing air and she couldn't figure it out! So when you "check" prssure, be prepared to add more.

Answer 7

50 psi, if the bike fits you the tire pressure is correct. always trust the pressure reccommended on the tire and or tube.

Answer 8

Get a new gage, then 52 psi

Answer 9

he's right. 52 psi.

Answer 10

put about 52psi