Go Back  Bike Forums > Bike Forums > Mountain Biking
Reload this Page >

Tire pressure?

Search
Notices
Mountain Biking Mountain biking is one of the fastest growing sports in the world. Check out this forum to discuss the latest tips, tricks, gear and equipment in the world of mountain biking.

Tire pressure?

Thread Tools
 
Search this Thread
 
Old 07-04-07 | 06:12 PM
  #26  
On-One/Titus USA
 
Joined: Apr 2007
Posts: 146
Likes: 0
From: PDX

Bikes: Lots +1

Originally Posted by Hal Fisher
How do you get an accurate reading with presta valves? I mean the guage on my pump just flys up and down when I'm adding so I have no idea what pressure I'm at.
ummm...Using a presta head pump the gauge will show your current pressure on the up stroke or when you stop pumping, just like when inflating a schrader valve.

I may also use a separate digital gauge.
shiggy is offline  
Reply
Old 07-04-07 | 06:13 PM
  #27  
On-One/Titus USA
 
Joined: Apr 2007
Posts: 146
Likes: 0
From: PDX

Bikes: Lots +1

Originally Posted by DylanTremblay
I just us the "squeeze tire with hand" method so I'm really not sure. But I keep mine pretty damn firm.
That may be accurate to +/-20psi.
shiggy is offline  
Reply
Old 07-04-07 | 07:54 PM
  #28  
Senior Member
 
Joined: Jun 2007
Posts: 212
Likes: 0
I like to change the tire pressure while I ride. Keep it high for the ride to the trails on pavement. Let it out at the trailhead. Back up for the ride home. Like 4x4's.
iwantakona is offline  
Reply
Old 07-04-07 | 08:01 PM
  #29  
Malistryx's Avatar
Senior Member
 
Joined: May 2007
Posts: 73
Likes: 0
From: Aussieland

Bikes: Specialized Allez Sport, Jamis Dakota Comp

I usually run 35psi, maybe 40 if I'm not doing anything technical. I'm also pretty light at 115lbs so I can get away with it
Malistryx is offline  
Reply
Old 07-04-07 | 08:05 PM
  #30  
Senior Member
20 Anniversary
 
Joined: Dec 2003
Posts: 1,295
Likes: 0
Originally Posted by Hal Fisher
How do you get an accurate reading with presta valves? I mean the guage on my pump just flys up and down when I'm adding so I have no idea what pressure I'm at.
When my floor pump does that it means that I have not attached the pump fitting to the valve stem correctly. The valve is not opening sufficiently. If it's attached correctly, you get a steady reading.

Possibly your fitting is not pushed far enough onto the valve stem. These fittings seem poorly designed. I had to ream mine out a little with a round file to fit correctly.

Al
Al.canoe is offline  
Reply
Old 07-05-07 | 08:51 PM
  #31  
On-One/Titus USA
 
Joined: Apr 2007
Posts: 146
Likes: 0
From: PDX

Bikes: Lots +1

Originally Posted by Al.canoe
When my floor pump does that it means that I have not attached the pump fitting to the valve stem correctly. The valve is not opening sufficiently. If it's attached correctly, you get a steady reading...

Al
I have never used a floor pump where the gauge does NOT do that. Just the way they work. The pressure spikes during the downstroke.
shiggy is offline  
Reply
Old 07-05-07 | 08:53 PM
  #32  
On-One/Titus USA
 
Joined: Apr 2007
Posts: 146
Likes: 0
From: PDX

Bikes: Lots +1

Originally Posted by Malistryx
I usually run 35psi, maybe 40 if I'm not doing anything technical. I'm also pretty light at 115lbs so I can get away with it
You can go lower. I out weigh you by 50-60 pounds and run less pressure.
shiggy is offline  
Reply
Old 07-06-07 | 01:54 AM
  #33  
Junior Member
 
Joined: Feb 2006
Posts: 12
Likes: 0
My wifes 2.0 Tiogas run 28 front 30 rear. My 2.1 I run 25 front and 28 rear. I have run as low as
20 without a problem. Running Stans no tubes. 1 weigh 170
Doug4sail is offline  
Reply
Old 07-06-07 | 04:20 AM
  #34  
Senior Member
20 Anniversary
 
Joined: Dec 2003
Posts: 1,295
Likes: 0
Originally Posted by shiggy
I have never used a floor pump where the gauge does NOT do that. Just the way they work. The pressure spikes during the downstroke.

We are addressing two different problems. I understood the problem to be that his gauge was not getting a steady reading during the upstroke. That's the problem I was addressing. I couldn't imagine anybody not knowing that the gauge will spike during the downstroke. But, I could have been mistaken.

Al
Al.canoe is offline  
Reply
Old 07-06-07 | 04:25 AM
  #35  
Senior Member
20 Anniversary
 
Joined: Dec 2003
Posts: 1,295
Likes: 0
Originally Posted by Doug4sail
My wifes 2.0 Tiogas run 28 front 30 rear. My 2.1 I run 25 front and 28 rear. I have run as low as
20 without a problem. Running Stans no tubes. 1 weigh 170

I have a friend who used to run his Stan's conversion in the very low 20's until his front tire burped and he ran off a bridge into a creek. He was about 40 lbs heavier than you at the time I think. However, it could be the tires as some hold the rim better than others.


Al
Al.canoe is offline  
Reply
Old 07-06-07 | 06:13 PM
  #36  
Orlock's Avatar
Plays in mud
 
Joined: May 2006
Posts: 31
Likes: 0
From: Pittsburgh, PA

Bikes: Gary Fisher Big Sur, Specialized Allez Elite Comp.

I run the front and rear tire at 25. However one time my rear tire was down to 15, I didn't get any flats but the bike sure was slow.
Orlock is offline  
Reply
Old 07-06-07 | 07:29 PM
  #37  
alumrock12's Avatar
the sun never sets on me
 
Joined: Oct 2006
Posts: 581
Likes: 0
From: the bAy

Bikes: 853 Hardtail

do the psi's differ if you run tubless compared to tubes?
alumrock12 is offline  
Reply
Old 07-06-07 | 08:28 PM
  #38  
On-One/Titus USA
 
Joined: Apr 2007
Posts: 146
Likes: 0
From: PDX

Bikes: Lots +1

Originally Posted by Al.canoe
We are addressing two different problems. I understood the problem to be that his gauge was not getting a steady reading during the upstroke. That's the problem I was addressing. I couldn't imagine anybody not knowing that the gauge will spike during the downstroke. But, I could have been mistaken.

Al
I think you are mistaken.
Originally Posted by Hal Fisher
...I mean the guage on my pump just flys up and down when I'm adding so I have no idea what pressure I'm at.
Has to be spiking on the downstroke, otherwise the gauge will not go up and down.
shiggy is offline  
Reply
Old 07-06-07 | 08:30 PM
  #39  
On-One/Titus USA
 
Joined: Apr 2007
Posts: 146
Likes: 0
From: PDX

Bikes: Lots +1

Originally Posted by alumrock12
do the psi's differ if you run tubless compared to tubes?
Only if you set the pressures differently.
shiggy is offline  
Reply
Old 07-06-07 | 11:05 PM
  #40  
Member
 
Joined: Jul 2007
Posts: 38
Likes: 0
From: NC
Depends on the tire and the tube. A lot of street riders who are jumping down flights of stairs and high **** like that run 60+. I run ~50 on my mt bike. If the front is low you will regret it on a sharp turn. Someone earlier said they have the back at a higher psi, i do the opp. I run it softer in the back so that I get more traction from my drive tire, especially in mud. Blue neon had the right idea, experiment. You don't want it to look squashed at all when you are just sitting on the bike
trainwrecked45 is offline  
Reply
Old 07-06-07 | 11:43 PM
  #41  
Obeying Gravity
 
Joined: Oct 2004
Posts: 2,962
Likes: 1
From: Bellingham, WA
Depends where I'm riding, and what tires I'm running.
MattP. is offline  
Reply
Old 07-07-07 | 04:46 AM
  #42  
Senior Member
20 Anniversary
 
Joined: Dec 2003
Posts: 1,295
Likes: 0
Originally Posted by shiggy
Only if you set the pressures differently.
The main reason folks in my area use tubeless is to run much lower pressures without the worry of pinch flats. The reason for lower pressures is for the higher speed and better traction. Some folks use them because they have a thorn problem in their area and it's a way to avoid flats.

I've ridden a trail is SE Tenn. (Bush Creek) where I was the only one out of four who didn't flat.

I use the Stan's conversion of tube tires vice true tubeless tires to save rotating mass as I like good acceleration. The tubeless tires are just too heavy. I do happen to have rims designed for tubeless tires, but with Stan's, that's not necessary.

Al
Al.canoe is offline  
Reply
Old 07-07-07 | 06:09 AM
  #43  
Senior Member
20 Anniversary
 
Joined: Dec 2003
Posts: 1,295
Likes: 0
Originally Posted by shiggy
I think you are mistaken.
Has to be spiking on the downstroke, otherwise the gauge will not go up and down.

Yup!

Al
Al.canoe is offline  
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.