Mountain Biking - What psi do you run?

Yes, I'm a newb. What is a good recommended psi for on and off road use?

30-40 psi for me

140psi

Depends on the situation, but I commonly run 25 to 30 up front and 40 in the back

Depends on the situation, but I commonly run 25 to 30 up front and 40 in the back

Carefull with that low psi...you could be replacing a lot of rims if you ride rough trails

usually something around 45 works best

Carefull with that low psi...you could be replacing a lot of rims if you ride rough trails

Are you telling Maelstrom to be careful with his pressure in the front...if so...HAHAHA!



usually something around 45 works best

Maybe for your trails/you/bike setup. The optimal pressure will depend on a lot of things...your bike setup, tire size, trails, your weight, riding style, etc...

I usually go a little high because i hate pinch flats and soft punctures. So around 37 or so.

Are you telling Maelstrom to be careful with his pressure in the front...if so...HAHAHA!




Maybe for your trails/you/bike setup. The optimal pressure will depend on a lot of things...your bike setup, tire size, trails, your weight, riding style, etc...

not really...take a hit at 25 on your front and you will crease your rim...I've adjusted by running a 2.1 on the front for "float" and a 1.95 rear fro "drive" on one of my bikes

And yes...tire pressure depends on a lot of things, but unless you want to work harder getting a soft tire to roll on the trails, more pressure is better than less. At 25 you will sacrifice speed and safety with that softer sidewall

not really...take a hit at 25 on your front and you will crease your rim...I've adjusted by running a 2.1 on the front for "float" and a 1.95 rear fro "drive" on one of my bikes

And yes...tire pressure depends on a lot of things, but unless you want to work harder getting a soft tire to roll on the trails, more pressure is better than less. At 25 you will sacrifice speed and safety with that softer sidewall

You're making a lot of assumptions here. You have no idea what kind of riding he does, so why are you suggesting what his tire pressure should be.

The same goes for the OP, optimum tire pressure depends on the rider, bike and terrain.

Carefull with that low psi...you could be replacing a lot of rims if you ride rough trails

usually something around 45 works best
Not with fat tires and DH tubes. I run 25-28 front and rear and haven't pinch-flatted in a year.

not really...take a hit at 25 on your front and you will crease your rim...I've adjusted by running a 2.1 on the front for "float" and a 1.95 rear fro "drive" on one of my bikes

And yes...tire pressure depends on a lot of things, but unless you want to work harder getting a soft tire to roll on the trails, more pressure is better than less. At 25 you will sacrifice speed and safety with that softer sidewall

You're assuming everyone rides cross country on smoother trails.

With one of my bikes, if I ran 45 psi up front I would be sacrificing speed and safety.

You're assuming everyone rides cross country on smoother trails.

With one of my bikes, if I ran 45 psi up front I would be sacrificing speed and safety.

maybe, my home trails are hardpacked forest...mostly sand, hence the 2.1 @45 front

However, i do ride the trails on Blue Mountan, our local 800' "hill...mostly limestone, clay, with rock gardens and roots

here I use a bike with 1.95 Nevegals on Mavic 717's, but also @ 45 psi...I find that a stiffer sidewall works best in the rocks. My wife rides DH DDY rims with Kenda Megas at about 40...those wide tires offer more cushion, but I can only fit up to 2.3 in the fork and chain stays on this bike

I guess this is what makes life interesting

So I'd be good running about 40 front and back until I get a feel for the trails?

So I'd be good running about 40 front and back until I get a feel for the trails?

40 works well

I"m strictly a XC rider on singletrack. I run tubes with Slime. PSI front and rear is 37 for all conditions.

For on road use the tire is hard when I pinch it between my thumb and index finger.

For off-road use the tire is squishy when I pinch it between my thumb and index finger.

Actually thats pretty much what I do. I haven't actually checked the exact pressure of any of my bike tires in a long time.

On the mountain bike my front is a little squishier than the rear.

As much as possible to lower rolling resistance but still keep traction. You will need to experiment to find the "sweet spot".

Tire pressure is one of the biggest factors that will affect the way your bike handles and rides.

Thanks for the advice JM01, I will take that into account next time I am pumping up my tires for whistler mountain (little taller and rougher than blue)...

Let me clarify...since "ranges" make people upset

Xc - 35 up front and 45 rear. I like a soft front for those nice rainy days when a square tire gets better traction on roots and rock faces than a round pointy 50psi. If I was riding the shore, I drop the psi a little more, head north to Kamloops, I increase by 5 to 10 psi. Different terrain, different weather, different needs. Most of the time, I am a set and forget, 30psi up front suits everything for me.

Dh - 25 to 30psi depending on the tire I am using, 40 in the rear max, usually closer to 35. On the muddy days I usually drop the pressure a little more. I know there are two lines of thinking on that. Narrow and high pressure cuts the mud, wide and low pressure sits on top. Since I weight enough to make any tire "cut" through mud, I figure I need any traction advantage I can take.

In all those setups, I have never pinch flatted. I am a very large rider with the skill of a ryno running through the woods. If I don't pinch flat I am either lucky or I am doing something right.

not really...take a hit at 25 on your front and you will crease your rim...I've adjusted by running a 2.1 on the front for "float" and a 1.95 rear fro "drive" on one of my bikes

And yes...tire pressure depends on a lot of things, but unless you want to work harder getting a soft tire to roll on the trails, more pressure is better than less. At 25 you will sacrifice speed and safety with that softer sidewall

Likely the difference, I don't/can't ride tires that small. My "xc" tire is 2.3. 1.95 is for my commuter tires.

140psi

4*35?

I am a very large rider with the skill of a ryno running through the woods.

LOL! A nimble rhino maybe.

LOL! A nimble rhino maybe.

You didn't see me in my tootoo did ya?...:D

No but thanks for the visual <fiercely gouges minds eye with coathanger>

Ouch! Ouch! Turn it off! Turn it offffffffff!!!!

27 to 29 front and 2 lbs more in the rear.

Al

New rider here, hope it's okay if I butt in but this is something I've been giving a lot of consideration. I just bought a 21 inch Rockhopper disc comp last saturday, took it straight to the woods from the shop, after they told me everything was ready to go. Nice ride, took it down about a 80 percent grade for a quarter mile over deep sand pockets, large loose rocks, foot deep rain ruts etc. at about thirty miles an hour, this would have exploded any bike I had when I was a kid and the rockhopper just ate it up.
But anyway, I was checking it out after and thought the tires seemed a little flat, now I'm a big guy, six foot three, three hundred pounds.
I went back to the shop and bought a pump and guage and after reading around these forums a bit put the pressure at fifty pounds.
My question was, when I checked the pressure those guys had it at it was only twenty five pounds. The tires are twenty six by two inch rated for thirty five to eighty pounds so it would appear they were inflated well under the rating. Are these tires okay to run at that low of pressure under the conditions I just described? Or do you think when the shop was checking out the bike they just forgot to air them up? Am I lucky not to have gotten a flat on my little suicide run? Or is that normal?
The tires are the stock "Specialized Adrenaline" tires.

I haven't taken it back out in the woods yet, still waiting for my butt to heal. :o)
But I'm already hooked.

Ouch! Ouch! Turn it off! Turn it offffffffff!!!!

haha and you haven't even met me yet...

note to self, rotten egg smell in marriott during stay :D

For me it depends on where I'm riding, what tires are mounted, who I'm riding with, the tide, moon phase, if I've had lunch, if I took a dump before we left, and any number of other variables which make it impossible to give anyone a straight answer in regards to tire pressure. Keep it in between what's written on the side wall of the tire and adjust to find your sweet spot.

haha and you haven't even met me yet...

I have an overactive imagination - - it's an art-hack thing.



note to self, rotten egg smell in marriott during stay :D
Haha!
"Made with real wolverine urine." - -

http://www.thwartcatrepellent.com/images/newbanna.gif

Haha!
"Made with real wolverine urine." - -

http://www.thwartcatrepellent.com/images/newbanna.gif
Actually the dead birds thing is the cat version of meals on wheels. You've made it obvious that you're a poor hunter and are unable to feed yourself so the cat is trying to feed you because it pities you.


Don't even get me started on people who let their pet cats run loose it won't end well.

I have this weird feeling I am out of some loop?...

Don't even get me started on people who let their pet cats run loose it won't end well.

loose cats make GREAT dog food and loose dogs make great pavement patches
BTW , I run between 18 and 35 psi on my Cinders,depending on if I feel like filling them weigh 200#, and ride aggressive XC. Ive oly had 1 pinch flat in 3 years that way and I believe I was below 18psi. my Mavic 321 rims clang on roots and rocks at below 20 but Ive yet to kock one out of true from it.
I ride with a fellow who is 260# and keeps his Cinders at 40-50psi and looks like he's riding on flat tires.
telling Mael how to keep his tires is like telling the wind how to blow. if anything you should be asking him for advice, not giving it

Actually the dead birds thing is the cat version of meals on wheels. You've made it obvious that you're a poor hunter and are unable to feed yourself so the cat is trying to feed you because it pities you.[/B].

Silly cats just dont understand the fine art of the microwave like D does.

45 psi trail.
110 psi road.

40-50 depending on how much trail and how much road.

Depends if you use hydrogen, helium, or air (mostly nitrogen). It is very complicated and I am tired and therefore will not go into detail.
Seriously, just ride a lot, try different PSI's and I'm sure you will figure it out.

Depends if you use hydrogen, helium, or air (mostly nitrogen). It is very complicated and I am tired and therefore will not go into detail.

I'm sure talking out of your ass is very complicated, and would make you too tired to go into detail. :rolleyes:

I have this weird feeling I am out of some loop?...Oh, it just digressed because of my obscure reference. I was trying to outdo you with something more obnoxious than rotten egg smell and came up with wolverine urine (one of the most noxious substances on the planet). But the only image I could find was of a product actually made with it. And then it just unraveled from there . . ..

There is this cool thing on the tubes. Called a valve. Fill when needed on the road, let some out when not needed off road.

Pedaling up the road to the top of the Ribbon in Fruita Tuesday morning, had mine filled to about 50psi. Dropped them down to ~30psi once at the trail portion of the ride.

No gauge there, but that is what I normally run most of my tires at, and I've grown accustomed to what they feel like by hand when letting air out.

*Generally speaking* larger volume tires and stiffer sidewalls will let you run much lower pressures. I've run some 2.7" Intense DH tires at 20psi with no ill effects.

As others have pointed out: what you ride, where you ride, and how you ride should be more indicative of what pressures you run than what a bunch of internet posters say.

Yes, I'm a newb. What is a good recommended psi for on and off road use?

Your optimum PSI is dependent on:

* Terrain
* Weight
* Tire Volume
* Riding Style

In general for off road riding you need to fill the tires with enough air so that there is a slight "bulge" at the bottom. This allows the tires to dynamically mold to the terrain which supplies the greatest amount of traction.

Some people take this to an extreme and run as little air pressure as possible. This is a recipe for pinch flats. Choose this at your tire changin' peril.

I suggest that you get yourself a frame pump to take on the trail with you. Play around with pressures until you get it right.

I'm sure talking out of your ass is very complicated, and would make you too tired to go into detail. :rolleyes:

Speaking of what is coming out of my @$$-- ahhh, methane! I never thought about that. Like hydrogen, it is less dense than air but it is flammable; something to be awary of around open flames. I would hate to see my new Kenda and Cinder go up in flames--- Cinder, go up in flames, that is funny.

But what psi did you run on the Andy's hike-a-bike?



Oh, upon getting to that point, it was instant deflation. I'm never pedaling up that damn road again, either.

I actuall never check the actual psi Im sure its around 40, i just keep them rock hard. Ive gotten too many pinch flats to go soft. plus you go faster on hard tires.

......... plus you go faster on hard tires.


Thats total BS.

I'm going with 40 on the trails to start, but what about on the beach? The same?

I'm going with 40 on the trails to start, but what about on the beach? The same?

Again two theories. Wide tires low psi sits on top. Narrow high psi cuts through the sand. Personally, I like wide low psi.

not to jack a thread, but i was riding some dry dry trails, and my back end slid out on a lot of the downhill turns. is this cause my rear tire has too much air?

I run 35-40. I tried 80, the max the tires were rated for, under the dilusion that I would have less rolling resistance and would increase my speed. :rolleyes: It went really fast right up until I hit the first log/bridge jump, then I crashed on what was an otherwise easy, routine jump. So much for that experiment.

not to jack a thread, but i was riding some dry dry trails, and my back end slid out on a lot of the downhill turns. is this cause my rear tire has too much air?

Could be the wrong tire for dry dry conditions.

It went really fast right up until I hit the first log/bridge jump, then I crashed on what was an otherwise easy, routine jump.

Yes, In my experience crashing usually decreases my speed too :p