Notices
Clydesdales/Athenas (200+ lb / 91+ kg) Looking to lose that spare tire? Ideal weight 200+? Frustrated being a large cyclist in a sport geared for the ultra-light? Learn about the bikes and parts that can take the abuse of a heavier cyclist, how to keep your body going while losing the weight, and get support from others who've been successful.

Tire pressure

Old 08-12-22, 09:57 AM
  #1  
Newbie
Thread Starter
 
Join Date: Apr 2012
Location: Pensacola, FL
Posts: 29

Bikes: 2013 Giant Defy 2

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Tire pressure

Hey y'all. I've been out of the cycling community for a while. I used to ride a lot about 10 years ago, but life happened and I had to hang up my cleats. I just recently purchased a "new" bike and began riding again. Recently I've been seeing articles online about lower pressure in your tires is better and can make you faster. I thought the school of thought was the more tire pressure, the less rolling resistance. Anyway, I run 25mm tires and found a calculator online that said the correct psi for my size and tire size is 94psi in the rear and 92 in the front. What tire pressure does everyone ride with and do you feel like a lower pressure makes you faster?
Suprdav95 is offline  
Old 08-20-22, 02:48 AM
  #2  
Old guy on a bike
 
Join Date: Dec 2018
Location: Central FL/ DownEast ME
Posts: 103

Bikes: Fuji “mountain” bike, Lynskey GR260 & Firefly Allroad

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 33 Post(s)
Liked 47 Times in 18 Posts
I like the Silca calculator and when I input all my info for my panaracer gravelking 32’s I got 67/64 front/rear
Then I measured the tires and they measure 36mm, and the calc changed to 55/53.
Takeaway is measure your tires if you want to use a calculator for pressure
Mmassey338 is offline  
Likes For Mmassey338:
Old 08-24-22, 09:27 AM
  #3  
Senior Member
 
mr_pedro's Avatar
 
Join Date: Sep 2012
Posts: 645
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 75 Post(s)
Liked 75 Times in 48 Posts
I get about the same for my 25 mm tires. Depends on your weight, surface conditions and speed.
More weight is more pressured, more speed is more pressure and better surface conditions is more pressure.
mr_pedro is offline  
Old 08-25-22, 09:00 AM
  #4  
Full Member
 
Join Date: Oct 2014
Location: KCMO
Posts: 200

Bikes: 2022 Ribble Endurance Disc Sport 2018 Trek Emonda Al4, 2012 Motobecane Heat Ti,

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 19 Post(s)
Liked 222 Times in 67 Posts
On my bikes that have clinchers, Gp4000s on one and Gp5000 on the other, both tires are 700x25. I inflate to 80 lbs. I way 240 lbs. I usually never have flats or other problems. On my newer bike that has tubeless tires (Schwable pro ones) 700 x 28 I inflate these to 65 lbs.

Hope that helps!
Frank72 is offline  
Old 08-25-22, 01:02 PM
  #5  
Senior Member
 
Join Date: Dec 2010
Location: northern Deep South
Posts: 8,891

Bikes: Fuji Touring, Novara Randonee

Mentioned: 36 Post(s)
Tagged: 0 Thread(s)
Quoted: 2593 Post(s)
Liked 1,922 Times in 1,206 Posts
I use the Silca calculator to find my ideal tire pressures, pump my tires up to 2-5 psi over those numbers...

and then use the thumb test to decide if I need to pump them up again in the next week or two.
pdlamb is offline  
Old 08-25-22, 04:25 PM
  #6  
Pennylane Splitter
 
Join Date: Sep 2012
Location: Orange County, California
Posts: 1,878

Bikes: Yes

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 1781 Post(s)
Liked 1,434 Times in 984 Posts
I just look at the sidewall of the tire and pump it up a little below the maximum pressure molded into the tire body. Currently alternating between two bicycles for daily road rides, running 700x32 and 700x35, and they get pumped up to about 75-80psi. I check it weekly and top off a necessary. No pinch flats, blow-outs, or other tire problems so it seems to be working.
skidder is offline  
Likes For skidder:
Old 08-29-22, 03:33 PM
  #7  
Senior Member
 
Milton Keynes's Avatar
 
Join Date: May 2016
Posts: 3,947

Bikes: Trek 1100 road bike, Roadmaster gravel/commuter/beater mountain bike

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 2281 Post(s)
Liked 1,710 Times in 936 Posts
Originally Posted by skidder
I just look at the sidewall of the tire and pump it up a little below the maximum pressure molded into the tire body. Currently alternating between two bicycles for daily road rides, running 700x32 and 700x35, and they get pumped up to about 75-80psi. I check it weekly and top off a necessary. No pinch flats, blow-outs, or other tire problems so it seems to be working.
That's what I do. On my road bike, which has tires with max. inflation of 110 PSI, I usually put in about 90. On my gravel bike with 65 PSI tires, I usually make sure they're at around 60.
Milton Keynes is offline  
Likes For Milton Keynes:
Old 09-01-22, 06:10 AM
  #8  
Newbie
 
1sp33d's Avatar
 
Join Date: Jul 2022
Posts: 62

Bikes: 2022 Cervelo Caledonia -- 2022 Surly Ghost Grappler

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 27 Post(s)
Liked 49 Times in 23 Posts
Originally Posted by Suprdav95
Hey y'all. I've been out of the cycling community for a while. I used to ride a lot about 10 years ago, but life happened and I had to hang up my cleats. I just recently purchased a "new" bike and began riding again. Recently I've been seeing articles online about lower pressure in your tires is better and can make you faster. I thought the school of thought was the more tire pressure, the less rolling resistance. Anyway, I run 25mm tires and found a calculator online that said the correct psi for my size and tire size is 94psi in the rear and 92 in the front. What tire pressure does everyone ride with and do you feel like a lower pressure makes you faster?
I'm in the same boat. Everything has changed in the last 10 years. After getting a flat, the guy at bike shop was being kinda jerky to me about pumping up my tires to max, like what used to be the recommendation. I had to explain I'm working from 10 year old bike knowledge. Now everything is about lower pressure.

Originally Posted by Mmassey338
I like the Silca calculator and when I input all my info for my panaracer gravelking 32’s I got 67/64 front/rear
Then I measured the tires and they measure 36mm, and the calc changed to 55/53.
Takeaway is measure your tires if you want to use a calculator for pressure
Thanks for recommending the Silca. I entered all my info to get their recommendations.
1sp33d is offline  
Old 09-04-22, 07:34 PM
  #9  
Newbie
 
Join Date: Sep 2022
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
I'm on GP5000's 700x28 and run in the ballpark of 100psi for most rides (Trek Emonda SL5 with Alto 52mm deep carbon wheelset). I'm 295ish. For some reason, lower pressures make me worry about stress on the wheelset. Good luck!
moborb is offline  
Old 09-09-22, 06:55 AM
  #10  
Thread Killer
 
Join Date: Aug 2008
Location: Ann Arbor, MI
Posts: 12,427

Bikes: 15 Kinesis Racelight 4S, 76 Motebecane Gran Jubilée, 17 Dedacciai Gladiatore2, 12 Breezer Venturi, 09 Dahon Mariner, 12 Mercier Nano, 95 DeKerf Team SL, 19 Tern Rally, 21 Breezer Doppler Cafe+, 19 T-Lab X3, 91 Serotta CII, 23 3T Strada

Mentioned: 30 Post(s)
Tagged: 0 Thread(s)
Quoted: 3129 Post(s)
Liked 1,696 Times in 1,026 Posts
Yeah, there’s lots of talk about “lower pressures,” but few really understand the context and variables, or at least fail to articulate the complexities.

It used to be that even light riders and racers would run +100psi on the road in as skinny a tire as they could find, like 20mm or even 19mm. That’s the context.

Is that applicable to clydes? Maybe; what kind of tire and size? What kind of roads? What kind of riding? That’s the complexity, as also expressed well by mr_pedro above.

Without knowing the OP’s weight and answers to other questions, we cannot begin to comment on what an optimized for speed pressure might be.

I’m 245lbs and push 700x25 tubeless racing rubber aggressively, but with experience and care (i.e. I don’t ride heavy in the saddle and slam stuff) over rough MI roads. That works out to 95/100-105psi F/R for me, depending on the tires. I have no idea if it’s optimized for speed, but it is optimized for my preferred feel at the wheels, comfort, and damage resistance.
chaadster is offline  
Likes For chaadster:
Old 09-09-22, 08:22 AM
  #11  
Senior Member
 
c_m_shooter's Avatar
 
Join Date: Sep 2006
Location: Paradise, TX
Posts: 2,087

Bikes: Soma Pescadero, Surly Pugsley, Salsa Fargo, Schwinn Klunker, Gravity SS 27.5, Monocog 29er

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 186 Post(s)
Liked 234 Times in 166 Posts
Lower pressures in a 25mm tire will just lead to more pinch flats. If your bike has room for 32mm, try those and you will be able to lower pressure to the 60-80 psi range depending on your riding style.
c_m_shooter is offline  
Old 10-31-22, 10:10 AM
  #12  
Newbie
 
Join Date: Oct 2022
Location: Seattle
Posts: 54

Bikes: Serotta Rapid Tour, 89 Paramount, AD Vent Noir, All-City Space Horse

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 28 Post(s)
Liked 109 Times in 37 Posts
I'm ~210 and usually aim for 75-80 on my 28mm gp5000s. I've only pinch flatted my rear once... when I decided to test the lower limits and hit a bump at 55psi. So now I play it safe(r).
pnwgopher is offline  
Old 11-07-22, 08:34 AM
  #13  
Senior Member
 
Join Date: Mar 2019
Posts: 1,606
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 581 Post(s)
Liked 921 Times in 518 Posts
25mm tires are pretty narrow, and narrow tires require higher pressure to avoid pinch flats. Also, insufficient pressure means the tire is compressing more than ideal and you lose energy to that flex. You might also notice 'squirming' or other undesirable handling traits with underinflated tires. So there are multiple reasons to continue to ride narrow or narrowish tires at high (~100psi or thereabouts) pressures.

Lower pressures are becoming more popular because many road bikes can accept fatter tires than in decades past - I have had more than one bike where 25mm seemed to be as wide as would fit, but I don't see my future self owning a bike that can't fit at least 32s.

So if sticking with 25mm tires, yeah, pressures in the 90s or 100s of psi are probably still a good idea. When you ride those tires enough to wear them out, see if you can fit wider tires for your next set and then enjoy the benefits of lower pressures. THere are many 'high-performance' (lightweight and light, supple casing) tires available in 28mm, perhaps fewer in 32mm, and only a few options above that. Lots of heavier and tougher tires in all sizes, but not so many 'fast' tires.
ClydeClydeson is offline  
Old 11-12-22, 06:38 PM
  #14  
The Wheezing Geezer
 
Fredo76's Avatar
 
Join Date: Oct 2021
Location: Española, NM
Posts: 1,043

Bikes: 1976 Fredo Speciale, Jamis Citizen 1, Ellis-Briggs FAVORI, Rivendell Clem Smith Jr.

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 411 Post(s)
Liked 895 Times in 440 Posts
I'm about 215 lbs, 6'2".

In p.s.i. front/rear, I run:

70/75 on 35mm clinchers,
80/85 on 28mm clinchers,
85/90 on 28mm sew-ups,
90/95 on 25mm clinchers,
95/100 on 23mm sew-ups.
Fredo76 is offline  
Old 11-13-22, 01:38 AM
  #15  
Senior Member
 
Join Date: Oct 2007
Location: NW
Posts: 747

Bikes: To many to list. I like them all!

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 60 Post(s)
Liked 43 Times in 32 Posts
I look at the sidewall of the tire and go by that. Maximum PSI on the back and then I run about 4 PSI less on the front to get a better bit/traction. Also it’s more comfortable on the handlebar’s when riding on chip-seal.
tim24k is offline  
Old 04-05-23, 10:46 PM
  #16  
Senior Member
 
Join Date: Jun 2013
Location: Yolo County, West Sacramento CA
Posts: 517

Bikes: Modified 26 inch frame Schwinn Varsity with 700c wheels and 10 speed cassette hub. Ryan Vanguard recumbent. 67cm 27"x1 1/4" Schwinn Sports Tourer from the 1980's. 1980's 68cm Nishiki Sebring with 700c aero wheels, 30 speeds, flat bar bicycle.

Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 131 Post(s)
Liked 141 Times in 102 Posts
Jan Hein of the Bicycle Quarterly is the guy who has changed everyone's perception of tire sizes and pressures needed. It is interesting to read his scientific experiments that led to the bigger tires and less pressure. His evidence is so strong that the Tour de France riders are now riding bigger and bigger tires with less and less pressure. Jan's evidence shows that it is sidewall flex that determines how efficient a tire is to pedal and bigger is better in all cases. Pressure has a big role in this. He has experimented up to 50mm tires that role easier than 25mm tires at over 100psi. I have changed my tire pressure habits and now experiment with pressure to find the sweet spot for the tires I'm using. My smallest tire on a road bike is 32mm at this time and I'm very happy with them.
tallbikeman is offline  
Old 04-24-23, 12:37 PM
  #17  
irc
Junior Member
 
Join Date: Mar 2010
Location: Scotland
Posts: 117

Bikes: Surly LHT, Surly Pacer, Spa Steel Tourer, Kona Kula

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 40 Post(s)
Liked 47 Times in 27 Posts
The pressure should be sufficient that when sitting on the bike the tyre sidewall deflects around 15% to 20% of it's height.

The pressure needed varies according to tyre width, tyre wall suppleness and wheel load. So with identical tyres the front will always be a good but lower pressure than the rear.
https://www.renehersecycles.com/tire...ure-take-home/

So no hard and fast rules. Except possibly just pumping up to the max pressure on the sidewalk is probably wrong.

.
irc is offline  
Old 05-22-23, 11:27 AM
  #18  
Junior Member
 
Breadfan's Avatar
 
Join Date: Feb 2023
Location: Jacksonville, Florida
Posts: 122

Bikes: Niner RLT 9, 1972 Nishiki Road Compe, Jamis Renegade, Specialized Roubaix

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 53 Post(s)
Liked 69 Times in 39 Posts
Originally Posted by tallbikeman
Jan Hein of the Bicycle Quarterly is the guy who has changed everyone's perception of tire sizes and pressures needed. It is interesting to read his scientific experiments that led to the bigger tires and less pressure. His evidence is so strong that the Tour de France riders are now riding bigger and bigger tires with less and less pressure. Jan's evidence shows that it is sidewall flex that determines how efficient a tire is to pedal and bigger is better in all cases. Pressure has a big role in this. He has experimented up to 50mm tires that role easier than 25mm tires at over 100psi. I have changed my tire pressure habits and now experiment with pressure to find the sweet spot for the tires I'm using. My smallest tire on a road bike is 32mm at this time and I'm very happy with them.
I read the same article and it also states that as long as your tires are not wider than you downtube, it will make no difference in speed, which they backed up with a lot of data. I'm 245 and I run 700x40 gravel tires, the rear is 50 psi and the front is 45 psi. I spent an entire afternoon testing. Too much pressure would slow me down over washboard and too little pressure would bottom out on rocks and roots, so I adjusted so neither would happen. The 50 and 45 psi that worked perfectly then gave me pinch flats so I went tubeless. I really didn't want to go tubeless, it was change, and for some reason I resist change on some things. I'm glad I tried it because there is no way I could have used those pressures, and those pressures were the sweet spot that I needed. It's all working now. I love it when a plan comes together. I'll never go back to tubes.

Last edited by Breadfan; 05-22-23 at 11:36 AM.
Breadfan is offline  
Old 05-28-23, 03:21 AM
  #19  
Senior Member
 
daviddavieboy's Avatar
 
Join Date: Oct 2013
Location: Great White North
Posts: 926

Bikes: I have a few

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 340 Post(s)
Liked 209 Times in 104 Posts
I mostly have the largest tire the bike will fit. Unfortunately on my fav bike at the moment it will only take a 25mm in the front and I use about 80-90 psi.
daviddavieboy is offline  
Old 06-03-23, 11:07 AM
  #20  
Full Member
 
Join Date: Jun 2008
Location: Canada
Posts: 358

Bikes: Devinci Millenium, Gary Fisher Joshua

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 73 Post(s)
Liked 29 Times in 13 Posts
Originally Posted by tallbikeman
Jan Hein of the Bicycle Quarterly is the guy who has changed everyone's perception of tire sizes and pressures needed. It is interesting to read his scientific experiments that led to the bigger tires and less pressure. His evidence is so strong that the Tour de France riders are now riding bigger and bigger tires with less and less pressure. Jan's evidence shows that it is sidewall flex that determines how efficient a tire is to pedal and bigger is better in all cases. Pressure has a big role in this. He has experimented up to 50mm tires that role easier than 25mm tires at over 100psi. I have changed my tire pressure habits and now experiment with pressure to find the sweet spot for the tires I'm using. My smallest tire on a road bike is 32mm at this time and I'm very happy with them.
Would you happen to have a link to the article? Thanks Al
alanf is offline  
Old 06-03-23, 07:57 PM
  #21  
Senior Member
 
Join Date: Jun 2013
Location: Yolo County, West Sacramento CA
Posts: 517

Bikes: Modified 26 inch frame Schwinn Varsity with 700c wheels and 10 speed cassette hub. Ryan Vanguard recumbent. 67cm 27"x1 1/4" Schwinn Sports Tourer from the 1980's. 1980's 68cm Nishiki Sebring with 700c aero wheels, 30 speeds, flat bar bicycle.

Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 131 Post(s)
Liked 141 Times in 102 Posts
Originally Posted by alanf
Would you happen to have a link to the article? Thanks Al
Alan years ago I signed up for e-mail updates from the Bicycle Quarterly and it was through these e-mails that I learned of all the tests that Jan had been party too. Check out the Bicycle Quarterly web page. I believe it might be a paid subscription but their e-mails are free. I believe you get more information paying for it but that is how I found out about this interesting series of tire tests.
tallbikeman is offline  
Old 06-07-23, 11:18 AM
  #22  
Senior Member
 
Join Date: Jul 2005
Posts: 5,988
Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 2493 Post(s)
Liked 737 Times in 521 Posts
21 posts and 21 different techniques, approaches, opinions ... I don't know, that makes me kind of sad. I am not going to add to the confusion. I will simply suggest some consideration when presented with a commercial concern publishing material that stands decades of manufacturing and performance practice on its ear.
Leisesturm is offline  
Old 06-07-23, 12:31 PM
  #23  
Senior Member
 
bbbean's Avatar
 
Join Date: Jul 2013
Location: Missouri
Posts: 2,690

Bikes: Giant Propel, Cannondale SuperX, Univega Alpina Ultima

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 672 Post(s)
Liked 416 Times in 248 Posts
Originally Posted by Suprdav95
Hey y'all. I've been out of the cycling community for a while. I used to ride a lot about 10 years ago, but life happened and I had to hang up my cleats. I just recently purchased a "new" bike and began riding again. Recently I've been seeing articles online about lower pressure in your tires is better and can make you faster. I thought the school of thought was the more tire pressure, the less rolling resistance. Anyway, I run 25mm tires and found a calculator online that said the correct psi for my size and tire size is 94psi in the rear and 92 in the front. What tire pressure does everyone ride with and do you feel like a lower pressure makes you faster?
First things first - yes, we have learned (and tested) that lower pressures are nearly always faster, ride better, and handle better. It is worth noting that the ideal pressure depends on the bike, road surface, rider weight, speeds ridden, etc. Knowing that I get great results with 25s at 75 psi doesn't really tell you how to adjust your own pressure if you don't know my weight, roads, speed, etc.

The best advice I've heard (short of using a couple of up to date respected online calculators like Zipp and Silca) is to start at the lowest pressure you're comfortable with, then drop pressure a few psi at a time until you recognize you've gone too far. Do that, and you'll have a much better idea of what works for you.
__________________

Formerly fastest rider in the grupetto, currently slowest guy in the peloton

bbbean is offline  
Old 06-07-23, 09:46 PM
  #24  
Newbie
 
Join Date: Mar 2023
Posts: 25
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Liked 11 Times in 7 Posts
I am on 35 mm tires, rated at 75 PSI. I fill them to 85 PSI, no problems at all.

I'm confused by the posts that say lower pressures go faster. Why? I'd think that with lower pressures, the tire will be less round and thus have more rolling resistance, no?
MagnaRota is offline  
Old 06-08-23, 11:23 AM
  #25  
Senior Member
 
bbbean's Avatar
 
Join Date: Jul 2013
Location: Missouri
Posts: 2,690

Bikes: Giant Propel, Cannondale SuperX, Univega Alpina Ultima

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 672 Post(s)
Liked 416 Times in 248 Posts
Originally Posted by MagnaRota
I am on 35 mm tires, rated at 75 PSI. I fill them to 85 PSI, no problems at all.

I'm confused by the posts that say lower pressures go faster. Why? I'd think that with lower pressures, the tire will be less round and thus have more rolling resistance, no?
Google is your friend. Lots of pages and videos that explain this, but basically, lower pressure reduces the rolling resistance and allows the tire casing to absorb more of the minute variations in surface as you ride. Imagine riding over rumble strips. With a very high pressure tire, your tire is going up and down each individual strip, requiring your entire bike to move up and down to move forward. Now imagine rolling over the same rumble strip on a tire with low enough pressure that the tire itself absorbs the up and down motion, so that your wheel and bike simply move smoothly forward parallel to the ground as if you were on smooth pavement.
You might also want to google "contact patch" to see the differences between high and low pressure.
__________________

Formerly fastest rider in the grupetto, currently slowest guy in the peloton

bbbean 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.