• 07-30-2013
    bluntrager
    How often do I need to put air in my tires?
    I was just wondering...how often do I need to check the air pressure in my tires and fill them up? I've only had my bike for about a month, but they already feel a bit lower than when I bought it.

    Notes: 29er, NOT tubeless
  • 07-30-2013
    advres
    I check my tires before every ride.
  • 07-30-2013
    hankscorpio
    If they feel low......check them. I find my tires lose air over the course of a week or two so usually I just put the pump on them to see the level and end up putting a a little in. If i'm riding back to to back days or something I might just go.
  • 07-30-2013
    s0ckeyeus
    I usually check before every ride, but you could probably do OK with checking once per week.
  • 07-30-2013
    IslandCrow
    At the very least, I'd at least check them manually (i.e. push down on them with your hand) before you head out. You'll quickly learn what feels right. If they're 2 or 3 psi off, it's hardly going to ruin your ride, but this will allow you to catch a tire that's getting really low. Otherwise, I actually hook it up to the pump and check the pressure about every few rides or before a long (well, long for me) ride.
  • 07-30-2013
    bluntrager
    Cool, thanks everyone. I just checked and it turns out I've been running about 10 psi too low. Whoops! Just curious, how would running 10 psi too low affect the way the bike rides? I mostly ride rocky singletrack with occasional sand.

    Looking back, I feel like the bike was really sluggish on the ups and really squirrely on the downs.
  • 07-30-2013
    hankscorpio
    PSI is a big debate on here. What are you running them at now? PSI really depends on the rider weight, tire, and conditions. A lot of people like to run lower pressure to get the most contact with the ground (better traction) If you run too low you are more likely to pinch flat.
  • 07-30-2013
    rangeriderdave
    The pressure is too low when you pinch flat or if you don't like the tire squrming around. Try some different pressures to see what you like.
  • 07-30-2013
    bluntrager
    Quote:

    Originally Posted by hankscorpio View Post
    PSI is a big debate on here. What are you running them at now? PSI really depends on the rider weight, tire, and conditions. A lot of people like to run lower pressure to get the most contact with the ground (better traction) If you run too low you are more likely to pinch flat.

    I'm running them at 30 psi right meow. I weigh about 200 pounds (trying to lose some of that though!). The tires are Bontrager 29-2. Conditions are always dry and rocky where I ride.
  • 07-30-2013
    In-Yo-Grill
    I check them before every ride and usually need to add a little bit.
  • 07-30-2013
    Surestick Malone
    I generally find I can get away with adding air every week or so on my MTBs and every few days on my road bike.

    They'll be down quite a bit by the end of a month.

    Invest in a floor pump, a simple one with no bells and whistles shouldn't be too expensive, $20-30. Get a high pressure one if you ever plan on getting a road bike, get a high volume one if you don't.
  • 07-30-2013
    Tystevens
    Quote:

    Originally Posted by bluntrager View Post
    Cool, thanks everyone. I just checked and it turns out I've been running about 10 psi too low. Whoops! Just curious, how would running 10 psi too low affect the way the bike rides? I mostly ride rocky singletrack with occasional sand.

    Looking back, I feel like the bike was really sluggish on the ups and really squirrely on the downs.

    Rocky singletrack will result in pinch flats if the pressure gets too low -- a pinch flat is when the tube gets pinched between a rock and the rim, causing a puncture or tear (and an almost instantaneous flat).

    I give my tires a squeeze before every ride, and put the pump on to check the pressure if it feels too soft or if it has been more than a week since I've ridden. I ride on lots of rocky terrain, and run my tires at around 40 psi (when I have tubes, at least) to avoid pinching. I also don't like a squirmy tire, so I run my tubeless almost as high.
  • 07-30-2013
    bluntrager
    Quote:

    Originally Posted by Surestick Malone View Post
    I generally find I can get away with adding air every week or so on my MTBs and every few days on my road bike.

    They'll be down quite a bit by the end of a month.

    Invest in a floor pump, a simple one with no bells and whistles shouldn't be too expensive, $20-30. Get a high pressure one if you ever plan on getting a road bike, get a high volume one if you don't.

    A floor pump would be good, I never realized how much effort a hand pump takes to get those suckers where they need to be hah. My hand pump does have a high pressure and a high volume setting though. And it works!
  • 07-30-2013
    bluntrager
    Quote:

    Originally Posted by Tystevens View Post
    Rocky singletrack will result in pinch flats if the pressure gets too low -- a pinch flat is when the tube gets pinched between a rock and the rim, causing a puncture or tear (and an almost instantaneous flat).

    I give my tires a squeeze before every ride, and put the pump on to check the pressure if it feels too soft or if it has been more than a week since I've ridden. I ride on lots of rocky terrain, and run my tires at around 40 psi (when I have tubes, at least) to avoid pinching. I also don't like a squirmy tire, so I run my tubeless almost as high.

    Is 40 too high for a 29er? The guy at my LBS said I shouldn't need to go above 32...
  • 07-31-2013
    jeffj
    Quote:

    Originally Posted by bluntrager View Post
    Is 40 too high for a 29er? The guy at my LBS said I shouldn't need to go above 32...

    IMHO, yes.

    I weigh 270 and I'm currently running Bontrager 29-3 tires (tubeless) on 19.5 mm inner width rims. I never need more than 30 psi and see no need to go over 32 psi for what you have described. In four years of running tubeless, I have never needed to tun more than 30 psi in any 29" tires.

    Performance will suffer with overly inflated tires as well as under inflated tires.
  • 07-31-2013
    hankscorpio
    The answer is really whatever you like best. The best advice I've read is to start somewhere (40 for example) and keep dropping 2 psi or so until you find the sweet spot or pinch flat. When I first started out on my Marlin also at about 200 lbs I was riding around 40 or maybe even a few higher. Then I started riding more comfortably around 35. Now on my WTB's i'm down to about 30-32
  • 07-31-2013
    Pilgrimm
    How often do I need to put air in my tires?
    I'm 160 soaking wet and I ride at between 34-36 depending on conditions. Tire pressure can affect ride performance, play around with with to see what you like. Those have always been my magic numbers.
  • 07-31-2013
    JoePAz
    Quote:

    Originally Posted by advres View Post
    I check my tires before every ride.

    Same here. I am running about as low a pressure as I want when using tubes and it easy to get small leak and lose a few psi. If I loose too much I can get a pinch flat on the trail. So best thing to check before each ride and set them right where I wan them 30psi front and 35 psi rear.
  • 07-31-2013
    Gasp4Air
    I change the air in my tires about once a week. Fresh air performs noticeably better than worn out stale air. Something about the molecular co-valences getting depleted, I think.

    Also, since I run tubeless, I have top off the pressure every couple of days.
  • 07-31-2013
    Kiwi_GR_Biker
    I had a puncture this week and realised it must have been a pinch flat because I haven't put air in my tires in months. I always checked them with my thumb but I think I have been running them way to low. After changing the tube on the side of the trail I repaired the old tube at home and it had two holes near the valve. I have a floor pump with a gauge and when I inflated the tyre to the recommended minimum of 27 psi it felt rock hard compared to previously. I hope the gauge is accurate. It's a pretty old pump. On the other hand I'm looking forward to riding the bike with the 're inflated tyres because the bike has been feeling a bit sluggish lately and I have been putting that down to my own fatigue and lack of fitness. It will be interesting to see how differently it handles on the trail. It feels so hard compared to before I'm worried the rear tyre may spin out on climbs. I guess I will find out next time out.

    Anyway lesson learned, I will be checking the air pressure at least once a week from now on.

    Oh yeah one other thing. The small hand pump I carry in my Camelbak does the job but it takes a lot of pumping to inflate the tyre to a level you can ride. Initially I didn't think it was working at all because the tyre didn't seem to be inflating but eventually could tell there was some air getting in there. Took a lot of further pumping to get the tyre inflated enough to ride home. What a PITA but I guess it is only for trail side repairs so hopefully not needed very often.
  • 07-31-2013
    Kiwi_GR_Biker
    Quote:

    Originally Posted by Gasp4Air View Post
    I change the air in my tires about once a week. Fresh air performs noticeably better than worn out stale air. Something about the molecular co-valences getting depleted, I think.

    Also, since I run tubeless, I have top off the pressure every couple of days.

    LOL - not sure if serious! :skep:
  • 07-31-2013
    Gasp4Air
    Quote:

    Originally Posted by Kiwi_GR_Biker View Post
    LOL - not sure if serious! :skep:

    Sure I'm serious. My riding buddies taught me this, said it was one of the secrets of the pros. Been doing it for years. Doesn't everyone do this? Huh? Anyone?

    :rolleyes:
  • 07-31-2013
    shiggy
    How often do I need to put air in my tires?
    Quote:

    Originally Posted by Gasp4Air View Post
    Sure I'm serious. My riding buddies taught me this, said it was one of the secrets of the pros. Been doing it for years. Doesn't everyone do this? Huh? Anyone?

    :rolleyes:

    I make sure I use front and rear specific air.
  • 07-31-2013
    Kiwi_GR_Biker
    Quote:

    Originally Posted by shiggy View Post
    I make sure I use front and rear specific air.

    Me too and specific air for the suspension fork that has to be replaced weekly. More than a week old and the fork won't perform to it's optimum.
  • 07-31-2013
    manbat
    Re: How often do I need to put air in my tires?
    I capture all my farts in an old irn bru bottle and save them up till theres about 80psi in there...then I inflate my standard tyres on ztr flow rims...they ALWAYS inflate super easy and stay up for months