Go Back  Bike Forums > Bike Forums > Fifty Plus (50+)
Reload this Page >

What Tire Pressure?

Notices
Fifty Plus (50+) Share the victories, challenges, successes and special concerns of bicyclists 50 and older. Especially useful for those entering or reentering bicycling.

What Tire Pressure?

Old 08-14-11, 09:16 AM
  #1  
Senior Member
Thread Starter
 
Join Date: May 2008
Posts: 2,712
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 41 Post(s)
Likes: 0
Liked 1 Time in 1 Post
What Tire Pressure?

I've read lots of threads and information on tire pressure. But, there is such a difference I'm still confused. Maybe this forum of elders can help.

The bikes I have use two different size tires: 7:00x23 and 7:00x38. My nominal weight is 190 pounds. I ride on really rough roads and often encounter glass and other sharp things on the road. I currently use max tire label air pressure with no problems but if a lower Safe pressure would bring more comfort I'm all for it.

What should I run in each bike?
ModeratedUser150120149 is offline  
Old 08-14-11, 09:36 AM
  #2  
Watching and waiting.
 
jethro56's Avatar
 
Join Date: Oct 2010
Location: Mattoon,Ill
Posts: 2,023

Bikes: Trek 7300 Trek Madone 4.5 Surly Cross Check

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 11 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
I wish it was easy to answer this. https://sheldonbrown.com/tires.html is one of the better sites and they don't actually spell it out.
jethro56 is offline  
Old 08-14-11, 09:40 AM
  #3  
tsl
Plays in traffic
 
tsl's Avatar
 
Join Date: May 2006
Location: Rochester, NY
Posts: 6,971

Bikes: 1996 Litespeed Classic, 2006 Trek Portland, 2013 Ribble Winter/Audax, 2016 Giant Talon 4

Mentioned: 21 Post(s)
Tagged: 0 Thread(s)
Quoted: 76 Post(s)
Likes: 0
Liked 14 Times in 9 Posts
I use the chart at PSI Rx as a starting point and experiment from there.

There's also a calculator based on it here.
tsl is offline  
Old 08-14-11, 10:01 AM
  #4  
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Posts: 30,225

Bikes: Catrike 559 I own some others but they don't get ridden very much.

Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 1572 Post(s)
Liked 644 Times in 365 Posts
I'm in roughly your weight class.

On my Klein I used to run 700 X 23c tires at 100 psi front and 110 psi rear. On my Bridgestone with 700 X 28c tires I used 90 psi front and rear. for 700 X 38c's I'd use a little less air pressure - maybe 80 or 85 psi.
Retro Grouch is offline  
Old 08-14-11, 10:27 AM
  #5  
Galveston County Texas
 
10 Wheels's Avatar
 
Join Date: Nov 2007
Location: In The Wind
Posts: 33,245

Bikes: 02 GTO, 2011 Magnum

Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 1354 Post(s)
Liked 1,249 Times in 626 Posts
It comes down to personal preference as long as you have enough psi to avoid pinched flats.
__________________
Fred "The Real Fred"

10 Wheels is offline  
Old 08-14-11, 10:28 AM
  #6  
Senior Member
 
donheff's Avatar
 
Join Date: Jun 2007
Location: Capitol Hill, Washington, DC
Posts: 1,503

Bikes: Specialized Tricross Comp, Custom Steel Sport Touring, Specialized Turbo Vado 4.0 SL

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 59 Post(s)
Liked 40 Times in 27 Posts
Originally Posted by tsl
I use the chart at PSI Rx as a starting point and experiment from there.

There's also a calculator based on it here.
+1 I use that too. Here is the chart. The article is definitely worth reading.



You need to accommodate the differing wheel loads to use the chart:

Attached Images
File Type: jpg
tirepressure.jpg (68.9 KB, 61 views)
File Type: jpg
tirepressureWheelLoad.jpg (26.1 KB, 40 views)

Last edited by donheff; 08-14-11 at 10:33 AM.
donheff is offline  
Old 08-14-11, 10:44 AM
  #7  
just keep riding
 
BluesDawg's Avatar
 
Join Date: Feb 2005
Location: Milledgeville, Georgia
Posts: 13,560

Bikes: 2018 Black Mountain Cycles MCD,2017 Advocate Cycles Seldom Seen Drop Bar, 2017 Niner Jet 9 Alloy, 2015 Zukas custom road, 2003 KHS Milano Tandem, 1986 Nishiki Cadence rigid MTB, 1980ish Fuji S-12S

Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 173 Post(s)
Liked 33 Times in 22 Posts
Experiment. As long as you aren't going so low that you get pinch flats on the rough roads, you are probably OK. I have never found a need to run the max pressure printed on a tire, not even when I weighed 220.

The charts can give you an idea where to start, but you don't need a weatherman to know which way the wind blows.
BluesDawg is offline  
Old 08-14-11, 10:59 AM
  #8  
Senior Member
 
Join Date: Jun 2010
Location: Pearland, Texas
Posts: 7,579

Bikes: Cannondale, Trek, Raleigh, Santana

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 308 Post(s)
Liked 5 Times in 5 Posts
HawkOwl, I'm close to your weight and I run 15% less than max pressure in both 23Cs on the roadie, 125 PSI max labeled at 100 PSI. The touring bike's tires are 35C and have a labeled range of 60-80 PSI. Unladen I run 60 PSI while 75 PSI worked well in the rear when loaded (no extra front loading).

These pressures have worked well riding Houston's sometimes less than stellar streets.

Brad
bradtx is offline  
Old 08-14-11, 11:05 AM
  #9  
Senior Member
 
Soma Roark's Avatar
 
Join Date: Apr 2010
Location: Los Angeles, CA
Posts: 378

Bikes: Trek 600 Series, Miyata 610, Palo Alto Touring, Schwinn Paramountain

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by donheff
+1 I use that too. Here is the chart. The article is definitely worth reading.



You need to accommodate the differing wheel loads to use the chart:

Yup, this is the way to go... in practice I just go around 80s, maybe 90's in the back since i ride more upright
Soma Roark is offline  
Old 08-14-11, 11:10 AM
  #10  
Senior Member
 
ItsJustAHill's Avatar
 
Join Date: Oct 2010
Location: NorCal
Posts: 188
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
If your roads are rough, I would consider swapping the 700 x 23s for a set of 700 x 25s. Doesn't sound like much, but it makes a difference on bad pavement. My two road bikes are currently on Michelin Pro Optimums, 80 psi front/85 psi rear. Very good puncture resistance with these as well.
ItsJustAHill is offline  
Old 08-14-11, 11:48 AM
  #11  
Senior Member
 
digibud's Avatar
 
Join Date: Oct 2009
Location: Further North than U
Posts: 2,000

Bikes: Spec Roubaix, three Fisher Montare, two Pugs

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
Note that Donheff's chart is referencing weight for each wheel of course and the rear wheel gets more weight. You can roughly figure your 190 lbs of weight results in 110lb of weight on the rear wheel and 100lb for the front (if your bike weighed about 20lb with tool kit and such). It doesn't matter if you're a few lbs off on those numbers. That would show you good starting points of about 110lb of pressure for the rear and 100 for the front. Dropping each of them 10lbs won't, in my experience, make much difference with regard to flats. It won't be too low to cause a pinch or so low it would pick up anything worse. Tire type and where you ride will have a much greater effect. My wife rides to my right most of the time and gets many more flats than I do because she is more apt to be catching worse junk. I've gotten one flat in the last 1000 mi this summer and she has probably gotten 4 before she decided to put on Gatorskins. The Gatorskins make a huge difference in comparison to our preferred Conti 4000S which I still use for day to day riding. I used my Gators for my recent Century+ ride. I also recommend 25C. The weight difference is minimal, as is the rolling resistance, but the lower pressure really does make the ride more comfortable. With your larger tires you can drop even more pressure before worrying about pinch flats. I can drop my 2.25 studded tires to 15lb if I want. You could drop a set of 25C to 85lb rear (I think) and get away with it safely. The horrible thing about pinch flats is they can happen in multiple places. You can end up with four holes in a tire. I only carry compressed air so they really have to be avoided! Just stay off really nasty roads like they have in Colorado and Alaska and you'll be OK.

Last edited by digibud; 08-14-11 at 11:49 AM. Reason: clarify
digibud is offline  
Old 08-14-11, 03:57 PM
  #12  
Senior Member
Thread Starter
 
Join Date: May 2008
Posts: 2,712
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 41 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Would a summary of: "Use the charts and experiment. Whatever feels good and doesn't give you flats is good." be fairly accurate? That certainly is what I've gotten from this thread. Of course I could be off base a little, or a lot.
ModeratedUser150120149 is offline  
Old 08-14-11, 04:13 PM
  #13  
Procrastinateur supreme
 
CrankyFranky's Avatar
 
Join Date: Sep 2006
Location: Franko barada nikto
Posts: 1,216

Bikes: Enough bikes...for today!

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 34 Post(s)
Liked 3 Times in 2 Posts
Originally Posted by HawkOwl
Would a summary of: "Use the charts and experiment. Whatever feels good and doesn't give you flats is good." be fairly accurate? That certainly is what I've gotten from this thread. Of course I could be off base a little, or a lot.
The caveat is simply that if you are riding in conditions which present large angular trap rock, etc. then you should forget about comfort achieved by slightly lowered pressure. So long as you've got modern rims and don't blow 'em off at max pressure, that's where i'd be. I just hate pinch flats.
CrankyFranky is offline  
Old 08-14-11, 04:23 PM
  #14  
Banned.
 
DnvrFox's Avatar
 
Join Date: Aug 2001
Posts: 20,917
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 12 Times in 10 Posts
120 psi front and back 700x25's 210 lbs. Done this for 13 years now, never a problem.
DnvrFox is offline  
Old 08-14-11, 04:58 PM
  #15  
Senior Member
 
digibud's Avatar
 
Join Date: Oct 2009
Location: Further North than U
Posts: 2,000

Bikes: Spec Roubaix, three Fisher Montare, two Pugs

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
I think Hawk Owl's got it. Some folks are tough enough they can run high pressure and not care. Others need to get as gentle a ride as possible. Both of my shoulders have fully torn rotator cuffs. 120 in both tires would be a literal pain for me. A chart...or the max pressure on the tire is a good starting point then experience will eventually take over. I experienced my wife's tire right into a pinch flat at one point...but now we have even more experience and she has as soft a ride as is reasonable. If I'd just pumped to 120 she'd be running for years with unnecessary harshness.
digibud is offline  
Old 08-14-11, 05:20 PM
  #16  
Senior Member
 
ericm979's Avatar
 
Join Date: May 2007
Location: Santa Cruz Mountains
Posts: 6,169
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 1 Time in 1 Post
https://www.michelinbicycletire.com/m...rpressure.view
ericm979 is offline  
Old 08-14-11, 05:50 PM
  #17  
Banned.
 
DnvrFox's Avatar
 
Join Date: Aug 2001
Posts: 20,917
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 12 Times in 10 Posts
"For riders above 180 lbs, inflate to maximum pressure indicated on tire sidewall"
DnvrFox is offline  
Old 08-14-11, 06:10 PM
  #18  
rebmeM roineS
 
JanMM's Avatar
 
Join Date: Jan 2006
Location: Metro Indy, IN
Posts: 16,216

Bikes: Bacchetta Giro A20, RANS V-Rex, RANS Screamer

Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 653 Post(s)
Liked 347 Times in 226 Posts
I don't entirely agree with this fellow:

Running 50F 80R for 32-559 85psi max tires on my long wheelbase bike with lightly-loaded front wheel - I really do need to weigh the bike to figure out the front/rear loading.
Attached Images
File Type: gif
michelin_man_hi.gif (81.6 KB, 16 views)
__________________
Bacchetta Giro A20, RANS V-Rex, RANS Screamer
JanMM is offline  
Old 08-14-11, 06:12 PM
  #19  
just keep riding
 
BluesDawg's Avatar
 
Join Date: Feb 2005
Location: Milledgeville, Georgia
Posts: 13,560

Bikes: 2018 Black Mountain Cycles MCD,2017 Advocate Cycles Seldom Seen Drop Bar, 2017 Niner Jet 9 Alloy, 2015 Zukas custom road, 2003 KHS Milano Tandem, 1986 Nishiki Cadence rigid MTB, 1980ish Fuji S-12S

Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 173 Post(s)
Liked 33 Times in 22 Posts
Originally Posted by DnvrFox
"For riders above 180 lbs, inflate to maximum pressure indicated on tire sidewall"
Written by lawyers, no doubt.
BluesDawg is offline  
Old 08-14-11, 07:05 PM
  #20  
Ridin' South Cackalacky
 
dahut's Avatar
 
Join Date: May 2010
Posts: 1,918
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by HawkOwl
I've read lots of threads and information on tire pressure. But, there is such a difference I'm still confused. Maybe this forum of elders can help.

The bikes I have use two different size tires: 7:00x23 and 7:00x38. My nominal weight is 190 pounds. I ride on really rough roads and often encounter glass and other sharp things on the road. I currently use max tire label air pressure with no problems but if a lower Safe pressure would bring more comfort I'm all for it.

What should I run in each bike?
Pump em up to max.
dahut is offline  
Old 08-14-11, 07:37 PM
  #21  
Senior Member
 
Join Date: Jun 2004
Location: Illinois (near St. Louis)
Posts: 852

Bikes: Specialized Expedition Sport, Surly LHT

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by tsl
I use the chart at PSI Rx as a starting point and experiment from there.

There's also a calculator based on it here.
+ 1 on PSI Rx. I run 35's at 80 PSI. Sidewall max is 110. MUCH more comfortable ride, and no noticeable difference in speed or perceived effort.
Dellphinus is offline  
Old 08-14-11, 08:49 PM
  #22  
Dan J
 
chinarider's Avatar
 
Join Date: Jul 2006
Location: Iron Mountain, MI
Posts: 1,244

Bikes: 1974 Stella 10 speed, 2006 Trek Pilot 1.2

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 18 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by HawkOwl
Would a summary of: "Use the charts and experiment. Whatever feels good and doesn't give you flats is good." be fairly accurate? That certainly is what I've gotten from this thread. Of course I could be off base a little, or a lot.
I think this is correct. For more opinions and info check this:https://www.bikeforums.net/showthread...for-road-bikes
chinarider is offline  
Old 08-15-11, 09:11 AM
  #23  
Senior Member
Thread Starter
 
Join Date: May 2008
Posts: 2,712
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 41 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Guess this group of elders has reinforced general opinion. I'm going to continue using the pressures I've been using since they work.
ModeratedUser150120149 is offline  
Old 08-15-11, 09:16 AM
  #24  
Senior Member
 
bobbycorno's Avatar
 
Join Date: Sep 2007
Posts: 2,454
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 6 Times in 6 Posts
Originally Posted by Retro Grouch
I'm in roughly your weight class.

On my Klein I used to run 700 X 23c tires at 100 psi front and 110 psi rear. On my Bridgestone with 700 X 28c tires I used 90 psi front and rear. for 700 X 38c's I'd use a little less air pressure - maybe 80 or 85 psi.
80 psi in a 700x38c is WAY overinflated. I'm 6'3", 185 lb and run my 650x38b's at 50 and 60 psi, and 700x25c's at 80 and 90. IME, optimal tire pressure is pretty much inversely proportional to width: ie, 38's are 1.5x as wide as 25's, so they should have 2/3 the pressure.

SP
Bend, OR
bobbycorno is offline  
Old 08-15-11, 09:16 AM
  #25  
Senior Member
 
bobbycorno's Avatar
 
Join Date: Sep 2007
Posts: 2,454
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 6 Times in 6 Posts
Originally Posted by dahut
Pump em up to max.
Why?

SP
Bend, OR
bobbycorno is offline  

Thread Tools
Search this Thread

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

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.