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Tire pressure?

Old 07-04-07, 06:12 PM
  #26  
shiggy
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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.
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Old 07-04-07, 06:13 PM
  #27  
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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.
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Old 07-04-07, 07:54 PM
  #28  
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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.
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Old 07-04-07, 08:01 PM
  #29  
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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
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Old 07-04-07, 08:05 PM
  #30  
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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
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Old 07-05-07, 08:51 PM
  #31  
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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.
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Old 07-05-07, 08:53 PM
  #32  
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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.
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Old 07-06-07, 01:54 AM
  #33  
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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
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Old 07-06-07, 04:20 AM
  #34  
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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
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Old 07-06-07, 04:25 AM
  #35  
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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
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Old 07-06-07, 06:13 PM
  #36  
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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.
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Old 07-06-07, 07:29 PM
  #37  
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do the psi's differ if you run tubless compared to tubes?
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Old 07-06-07, 08:28 PM
  #38  
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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.
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Old 07-06-07, 08:30 PM
  #39  
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Originally Posted by alumrock12
do the psi's differ if you run tubless compared to tubes?
Only if you set the pressures differently.
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Old 07-06-07, 11:05 PM
  #40  
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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
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Old 07-06-07, 11:43 PM
  #41  
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Depends where I'm riding, and what tires I'm running.
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Old 07-07-07, 04:46 AM
  #42  
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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
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Old 07-07-07, 06:09 AM
  #43  
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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
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