Results 1 to 25 of 28
Thread: MTB tire pressure?
-
08-14-2005, 05:06 PM #1
MTB tire pressure?
I was recently out riding with a group. One guy got a flat and we were eating huckleberries while he was fixing it talking tire pressure. The flat guy was running about 20psi and the others were runnig about 25psi. After all the snake bites I got this spring I've been running about 40-45psi. I recently softened up my suspensions and took the tube out of the back tire (mofo dh) my front tire has a heavy enough sidewall (Rokko ceramic) that I can almost ride with no air so I left the tube in. So what pressure would be a safe pressure to prevent flats but yet give me some traction on the rocks. 45psi sucks on rocks.
You are what you eat.
---------------------------------------------------
There's no such thing as bad snow, just shitty skiers.
-
08-14-2005, 05:12 PM #2
I hate to be that guy but it totally depends on the tire, rider, terrain, etc.
Lower it 3psi at a time until you start getting flats, then go back up a few psi.
-
08-14-2005, 06:55 PM #3
I run 26.57 back, 23.21 front. Yup.
Live To Ski!
-
08-14-2005, 09:01 PM #4
45 uphill and 18 going down. I don't get snakebites till about 12 lbs, on 2 ply tires. But I don't do drops either.
I want a 6" travel 20lb MTB. I found the 20lb MTB, but only good for riders under 87 pounds.
-
08-14-2005, 09:04 PM #5
Might want to also consider the strength of your rims and their width.
-
08-14-2005, 09:05 PM #6
Front Range XC, whats the general psi to run? 45?
-
08-14-2005, 09:10 PM #7Originally Posted by GT40Live To Ski!
-
08-14-2005, 09:14 PM #8Originally Posted by AfroMulletI want a 6" travel 20lb MTB. I found the 20lb MTB, but only good for riders under 87 pounds.
-
08-14-2005, 09:25 PM #9Originally Posted by AfroMullet
I run 22psi in the front with a Michi Comp32 on a D521 rim and 26 in the rear with a Comp16 on a D321. I weigh 175lbs, and this is for straight up downhill riding.
-
08-14-2005, 09:35 PM #10yelgatgab
- Join Date
- Oct 2002
- Location
- Shadynasty's Jazz Club
- Posts
- 10,249
I found that (on narrow rims) anything ~18 psi or under, and the tire won't pinch flat because there's not enough pressure to blow it out when it pinches. It works well, but you run the risk of damaging the rim. In my experience, with normal tires and tubes, 20-40 psi is the danger zone.
Go tubeless (or Stan's or Ghetto Stan's) or get heavier duty tubes. The thorn resistant tubes work well and aren't as heavy as DH tubes.Remind me. We'll send him a red cap and a Speedo.
-
08-14-2005, 10:30 PM #11
What exactly is Ghetto Stans?
-
08-14-2005, 11:55 PM #12Originally Posted by powwrangler
-
08-15-2005, 09:24 AM #13
Ghetto Stan's That's what I've done to my back tire. Two days, 1 ride, and I've still got 20psi.
You are what you eat.
---------------------------------------------------
There's no such thing as bad snow, just shitty skiers.
-
08-15-2005, 10:52 AM #14
My trail tires are at 35.
My DH tires are around 25-28.
-
08-15-2005, 04:01 PM #15Originally Posted by descender
Yeah, pretty similar. My trail bike has a pretty beefy Nokian NBX 2.35 UST up front that i run at 30, conti vert pro rear UST 35 psi.
My freeride, 25 front and rear. with stan's tubeless. I don't change pressure from climbing to descending. 25 seems to be good for both.
As already stated, the terrain, the tires, UST vs tubes, rider weight; all factor into tire pressure. There is alot of fine tuning involved depending on those factors.
-
08-15-2005, 10:24 PM #16Originally Posted by Z
I rarely get flats and of course last weekend i got 2 in the same day, but i believe the goat head was still in the tire causing the second flat, also from some drifting high speed airs which may have put some pressure on said goat head.More fucked up than a cricket in a hubcap
-
08-15-2005, 10:39 PM #17Originally Posted by Crinkle
-
08-16-2005, 09:26 AM #18
15-25 for DH, depends on conditions. On my old bike w/doublewides, you could easily run under 10. Those suckers would NEVER blow off the rim.
40+ going uphill on roads or smooth trails, lowered to 25-30 for the descent."Life should not be a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming, "Wow, what a Ride!"
-
08-16-2005, 09:41 AM #19
Don't forget to factor in the tire casing width you're running.
Road tire: 700x23c: 120 psi - but you can still squeeze the sidewalls
Mtn tire: 26x1.0 street slick: 90 psi - hard as a rock
Mtn tire: 26x1.95-2.1 XC knobby: I need to run tires of this size around 38-45 psi depending on terrain, or I'll get pinch flats.
Mtn tire: 26x2.5 DH/FR knobby: never ridden tires of this size, but since the volume is higher, a lower tire pressure = firmer tire.
My point is that a mtn XC tire at 40 psi is pretty firm due to its casing volume; a road tire at 40 psi is unrideable. So we can't just compare psi without including the type of tire, as well as the other factors (type of terrain, weight of rider)
-Karl
-
08-16-2005, 10:02 AM #20Originally Posted by Beaver
can you just uses stans for that???
-
08-17-2005, 05:23 PM #21
bump for my question ...
-
08-17-2005, 05:25 PM #22
I believe when Stan's first came out they included mold builder instead of the sealant used presently. I remember having to mix something.
Live To Ski!
-
08-17-2005, 05:37 PM #23Originally Posted by AfroMullet
so now, just use stan's in the cheap set up?
-
08-18-2005, 09:23 AM #24Originally Posted by mntlion"Life should not be a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming, "Wow, what a Ride!"
-
08-18-2005, 09:57 AM #25
Mold builder is cheap. I got enough to do about 100 tires for $15cad. Even cheaper on ebay
I went out yesterday with about 15psi in the back tire. I felt a couple rocks hit the rim but nothing too hard. I might put in a couple more pounds.Last edited by Beaver; 08-18-2005 at 10:00 AM.
You are what you eat.
---------------------------------------------------
There's no such thing as bad snow, just shitty skiers.
Bookmarks