Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Recreational Cyclocross and Gravelbiking This has to be the most physically intense sport ever invented. It's high speed bicycle racing on a short off road course or riding the off pavement rides on gravel like :The Dirty Kanza". We also have a dedicated Racing forum for the Cyclocross Hard Core Racers.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 08-17-12, 01:32 PM   #1
masonpb
Junior Member
Thread Starter
 
Join Date: Aug 2012
Location: Denver, CO
Bikes:
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Tire Pressure?

Realize it varies depending on the surface, temps, conditions, etc but curious on the general rule of thumb for knobby tires on the road vs on dirt/gravel. Thanks.
masonpb is offline   Reply With Quote
Old 08-17-12, 02:09 PM   #2
rithem
Foward Leaning Attitude
 
rithem's Avatar
 
Join Date: Mar 2005
Location: RHODE-MF-ISLAND
Bikes:
Posts: 851
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by masonpb View Post
Realize it varies depending on the surface, temps, conditions, etc but curious on the general rule of thumb for knobby tires on the road vs on dirt/gravel. Thanks.

don't forget body weight ...
rithem is offline   Reply With Quote
Old 08-17-12, 02:26 PM   #3
masonpb
Junior Member
Thread Starter
 
Join Date: Aug 2012
Location: Denver, CO
Bikes:
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks...145 lbs. Was thinking 30psi for dirt/gravel and 60 for road?
masonpb is offline   Reply With Quote
Old 08-17-12, 02:40 PM   #4
Fat Boy
Wheelsuck
 
Fat Boy's Avatar
 
Join Date: Jun 2007
Bikes:
Posts: 6,158
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Tire size?
Fat Boy is offline   Reply With Quote
Old 08-17-12, 02:40 PM   #5
rithem
Foward Leaning Attitude
 
rithem's Avatar
 
Join Date: Mar 2005
Location: RHODE-MF-ISLAND
Bikes:
Posts: 851
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by masonpb View Post
Thanks...145 lbs. Was thinking 30psi for dirt/gravel and 60 for road?
30 would be ok for your weight for a clincher, for racing ... you could go as low as 20 or even 18! on a tubular. For every day riding >30psi probably fine.
rithem is offline   Reply With Quote
Old 08-17-12, 10:12 PM   #6
obrentharris 
Senior Member
 
obrentharris's Avatar
 
Join Date: May 2012
Location: San Francisco Bay Area
Bikes: fewer (n-1)
Posts: 1,200
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 39 Post(s)
In my part of the world where 'cross courses often have concrete curbs, tree roots, broken rock, and hard-packed dirt, 30 pounds in clinchers will get you a pinch flat in no time. 50 pounds would be more reasonable but, unless you are very light on the bike, you'll still get the occasional pinch flat... Number one argument for racing on tubulars.
Brent
obrentharris is offline   Reply With Quote
Old 08-18-12, 05:50 AM   #7
simonaway427
Senior Member
 
Join Date: Apr 2010
Location: Fredericton, NB, Canada
Bikes: 2010 S1, 2011 F75X
Posts: 1,430
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I'm 160lbs on a 17lb bike.

I ran 35f/38r psi on my 34mm clinchers last year for racing. I bottomed out lots on roots and curbs, but never pinch flatted - although I'd imagine it would have been a matter of time.

I'm on tubs this year, planning on 28-32psi for those.

I run 50psi if i ride on the road on those tires. Nice compromise between comfort and rolling resistance.
simonaway427 is offline   Reply With Quote
Old 08-19-12, 12:19 PM   #8
rithem
Foward Leaning Attitude
 
rithem's Avatar
 
Join Date: Mar 2005
Location: RHODE-MF-ISLAND
Bikes:
Posts: 851
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by obrentharris View Post
In my part of the world where 'cross courses often have concrete curbs, tree roots, broken rock, and hard-packed dirt, 30 pounds in clinchers will get you a pinch flat in no time. 50 pounds would be more reasonable but, unless you are very light on the bike, you'll still get the occasional pinch flat... Number one argument for racing on tubulars.
Brent
rule of thumb on racing pressure, you should bottom out without pinch flatting once or maybe twice per lap --- it's all about being smooth and picking good lines, 50 psi will make a wreck of your corning skills in short order.
rithem is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -6. The time now is 08:42 PM.