Do you generally pump up to the max PSI? below? over?
05-06-08, 06:46 AM
#26
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... I'd like to go lower, but (I may be wrong, correct me please if so) it is my understanding that one of the three things that keeps tires on carbon tubies is tire pressure (the other two being glue and curvature of the rim. I was also told by the mechanic that the chemical bond between glue and carbon is a lot weaker than between glue and aluminum--true? I dunno).
Read that paper. It is very informative.
05-06-08, 06:57 AM
#27
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My tires are rated 170, so I pump to 120 or more I am 150. No teeth chatter for me.
05-06-08, 07:06 AM
#28
Bike ≠ Car ≠ Ped.
Fixed it now.
05-06-08, 08:10 AM
#29
shedding fat
180 Lb give or take. Tubular tires rated to 180 PSI. I pump both to 110 PSI always.
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Arguing with ignorant people is an exercise in futility. They will bring you down to their level and once there they will beat you with their overwhelming experience.
05-06-08, 09:50 AM
#33
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I'm keeping my mouth shut on this one. I figured someone would at least point to it by now. 
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05-06-08, 09:51 AM
#34
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05-06-08, 10:14 AM
#36
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https://www.bikeforums.net/road-cycling/410701-psimet-s-tip-day.html
edit: haha, just read the page 2 posts from psimet. This thread contains all you need to know. I just went down on my pressures - 95 front, 105 back. About 10 - 15 psi less than that marked on the sidewall.
edit: haha, just read the page 2 posts from psimet. This thread contains all you need to know. I just went down on my pressures - 95 front, 105 back. About 10 - 15 psi less than that marked on the sidewall.
05-06-08, 10:45 AM
#38
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I air up every few days based on what my tires look like when I pinch them and when I'm on the bike. I used to air up to the max it said on my tire (usu 100-110).
The other day I noticed she rolled away from me on a slight downhill when we "raced" from a dead stop. Now my bike is lighter, has carbon bits, and costs at least 3x as hers and the only other obvious difference is that I religiously pump my tires to 100-110 and hers to 75-85 (for comfort). I'm starting to think that rolling resistance is coming into play here.
The other day I noticed she rolled away from me on a slight downhill when we "raced" from a dead stop. Now my bike is lighter, has carbon bits, and costs at least 3x as hers and the only other obvious difference is that I religiously pump my tires to 100-110 and hers to 75-85 (for comfort). I'm starting to think that rolling resistance is coming into play here.
05-06-08, 10:47 AM
#39
Peloton Shelter Dog
Conti GP 4000 clinchers, 120psi. Conti Sprinter tubulars, 160 psi.
That is all.
By the way, that's been working since 1992/3, so it's not changing anytime soon. But feel free to do some BF hand wringing over it, that's the entertainment here.
That is all.
By the way, that's been working since 1992/3, so it's not changing anytime soon. But feel free to do some BF hand wringing over it, that's the entertainment here.
05-06-08, 11:44 AM
#41
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I pump mine up to 100 psi front, 110 psi rear.
My tires are rated for 120, and I used to keep them pretty close to that. I enjoy the ride much more now that I have the tires at a lower pressure.
My tires are rated for 120, and I used to keep them pretty close to that. I enjoy the ride much more now that I have the tires at a lower pressure.
05-06-08, 12:22 PM
#42
Senior Member
You and your bike's weight determine what tire pressure to use, not the max listed on the sidewall. Use this chart. The chart is for one wheel's worth of load so if you weight 180, your bike weighs 20, then together you weigh 200 and each wheel load is 100 lbs. Find 100 lbs on the x (horizontal) axis and go up to your tire and then go left to the y axis to find what psi you should use.
If you find the psi you need is up close to the max psi printed on the sidewall the solution is simple, get a wider tire.
If you find the psi you need is up close to the max psi printed on the sidewall the solution is simple, get a wider tire.
05-06-08, 01:18 PM
#43
AiM SmAlL mIsS sMaLl
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So according to the chart you just posted i should be going to 125/120, but I am currently on 110/105 and the ride is great and any more pressure and the ride feels like crap even with the carbon fork and carbon supports and the zertz (allez elite A1 frame)
05-06-08, 02:48 PM
#47
Portland Fred
For most tires, I like to ride around 120psi for most conditions. I drop that slightly for wet, cold, and when there is a lot of small debris.
Riding tires a bit hard has other advantages. For one thing, you can usually detect small leaks a lot faster. A little extra time to know you have a tire going down can be a big deal in a high speed descent.
05-06-08, 02:55 PM
#49
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dang, after reading this I decided to knock 10psi off my rear tire just for laughs, and pumped it up to 110 this morning. 3 miles into my lunch ride and BLAM, not only do I flat, I shred my tire (Conti GP4000).
Back to 120 for me.
(note total lack of empirical evidence that the lower pressure was the cause of my travails, but that I'll go ahead on that assumption anyway)
Back to 120 for me.
(note total lack of empirical evidence that the lower pressure was the cause of my travails, but that I'll go ahead on that assumption anyway
)
05-06-08, 03:01 PM
#50
Senior Member
Cool - I was hoping for a weird and wonderful explanation to be honest!