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


Go Back   > >

Mountain Biking Mountain biking is one of the fastest growing sports in the world. Check out this forum to discuss the latest tips, tricks, gear and equipment in the world of mountain biking.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 09-01-06, 05:28 PM   #1
Tam
Junior Member
Thread Starter
 
Join Date: Aug 2006
Bikes:
Posts: 12
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
PSI anyone?

So after looking over my new Rockhopper 07 and with a fingerprint duster mind you I found that the tires on it read that they take 35-85 psi. My question to everyone who's been doing this much longer than me is... What pressure do I use for trails with roots, stumps, up hills, down hills, etc. Oh, and 85 psi seems like it would make the tire explode. I have been filling them to about 40 psi.

Thanks
Tam is offline   Reply With Quote
Old 09-01-06, 05:32 PM   #2
Maelstrom 
Wood Licker
 
Maelstrom's Avatar
 
Join Date: Apr 2002
Location: Whistler,BC
Bikes: Transition Dirtbag, Kona Roast 2002 and specialized BMX
Posts: 16,885
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
On my ht

30psi front
30ish rear

Dually
30psi front
45psi rear
Maelstrom is offline   Reply With Quote
Old 09-01-06, 05:33 PM   #3
jag89
Eat my Dust... n00bs
 
jag89's Avatar
 
Join Date: Aug 2005
Location: Area 51
Bikes: Kona Cinder Cone 2006
Posts: 364
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
on my bike i have 45-50 in front and rear.
jag89 is offline   Reply With Quote
Old 09-01-06, 06:01 PM   #4
LowCel 
Throw the stick!!!!
 
LowCel's Avatar
 
Join Date: Apr 2003
Location: Charleston, WV
Bikes: GMC Denali
Posts: 17,588
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I generally run between 35 and 40 psi depending on course and conditions. However I run tubeless so this probably won't help you out too much.
__________________
I may be fat but I'm slow enough to make up for it.
LowCel is offline   Reply With Quote
Old 09-01-06, 06:02 PM   #5
Flak
Flatland hack
 
Flak's Avatar
 
Join Date: Nov 2005
Location: Nowhere near the mountains :/
Bikes:
Posts: 3,228
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I run 40-35ish

Its not worth risking a pinch flat to go any lower imo.
__________________
My shop - www.spinbikeshop.com
My team - www.teampanther.com
Flak is offline   Reply With Quote
Old 09-01-06, 06:09 PM   #6
Falanx
THE Materials Oracle
 
Falanx's Avatar
 
Join Date: Feb 2006
Location: Finally... home :-)
Bikes: Univega Alpina 5.1 that became a 5.9, that became a road bike... DMR TrailStar custom build
Posts: 502
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
35 front, 40 rear, full rigid. Front is a 2.1 and rear a 2.3, both Contis, though....
Falanx is offline   Reply With Quote
Old 09-01-06, 06:53 PM   #7
DylanTremblay
...is my hero!
 
DylanTremblay's Avatar
 
Join Date: Aug 2005
Location: Edmonton, Alberta
Bikes: 2008 Kink Whip, 2006 Specialized Enduro, 2006 Norco Wolverine, 2006 Iron Horse FsZ
Posts: 864
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I run 40 front, 50 rear on both my HT and FS.
DylanTremblay is offline   Reply With Quote
Old 09-01-06, 06:56 PM   #8
taylor p
Senior Member
 
taylor p's Avatar
 
Join Date: Jul 2006
Location: Brainerd MN
Bikes:
Posts: 999
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
about 40 psi on may ht
taylor p is offline   Reply With Quote
Old 09-01-06, 07:03 PM   #9
Defiance
Senior Member
 
Join Date: Apr 2006
Bikes:
Posts: 410
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Most of the time I'm using by bike on the street, so both wheels are around 55-60 psi. Sometimes I lower the front for more grip. On trails though, both go down to 40-45.
Defiance is offline   Reply With Quote
Old 09-01-06, 07:14 PM   #10
wethepeople
Long haired freak.
 
wethepeople's Avatar
 
Join Date: Jun 2005
Location: Still stuck in hell.
Bikes: 2011 SE Old Man Flyer.
Posts: 6,280
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
BMX: 110 front, 120 back.

Fully: 35 front, 40 back.

Hardtail: 40 front, 45 back.
__________________

"the bus came by and I got on, that's when it all began...there was Cowboy Neal at the wheel of a bus to never-ever land."

wethepeople is offline   Reply With Quote
Old 09-01-06, 09:04 PM   #11
Roxter
I=Your Mother
 
Join Date: Jun 2006
Location: Hamilton,Ontario,Canada
Bikes: 2003 Rocky Mountain Element
Posts: 232
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
for my boulder i pump them all the way up to 60 no matter what course i'm racing or riding. I love a harsh ride and i like to feel absolutely everything.
Roxter is offline   Reply With Quote
Old 09-01-06, 09:25 PM   #12
Maelstrom 
Wood Licker
 
Maelstrom's Avatar
 
Join Date: Apr 2002
Location: Whistler,BC
Bikes: Transition Dirtbag, Kona Roast 2002 and specialized BMX
Posts: 16,885
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Flak
I run 40-35ish

Its not worth risking a pinch flat to go any lower imo.

I should mention I only run dh grade tires. Pinch flats happen a lot less infrequently. If I were running standard xc tires...45ish probably.
Maelstrom is offline   Reply With Quote
Old 09-01-06, 09:53 PM   #13
jiiiim
Noobhead
 
jiiiim's Avatar
 
Join Date: Jul 2006
Location: SoCal
Bikes: k2 Zed 4.0
Posts: 688
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
(xc ht) 40-45 front and back
jiiiim is offline   Reply With Quote
Old 09-02-06, 12:27 AM   #14
ScareyH22A
Noob
 
ScareyH22A's Avatar
 
Join Date: Apr 2006
Location: Orange County, CA
Bikes: '06 Trek 8500
Posts: 119
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I ran 50 front and back a couple of days ago and noticed that my rear slips on some rocks. And my fronts a little squirmish. I think I should back off about 5 lbs each and try again.
ScareyH22A is offline   Reply With Quote
Old 09-02-06, 01:56 AM   #15
blue_neon
Elite Rep
 
Join Date: Aug 2004
Location: Melbourne - Australia
Bikes:
Posts: 2,096
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Everyone will ride different PSI depending on their weight. So you can't really go off someone else. (Just try experimenting...buy a pressure gauge and take it on the trails with you to check different pressures and get an idea!).

But here is mine anyway:

50PSI - Road, Bike Paths Gravel

35PSI - Hard Packed single track, loose gravel, going faster offraod, roots, logs, jumps.

25-30PSI - Wet, Muddy, single track, very loose conditions. NO jumps, NO roots, NO logs. (pinch flats arn't the funnest thing to fix and have).

blue_neon is offline   Reply With Quote
Old 09-02-06, 01:57 AM   #16
blue_neon
Elite Rep
 
Join Date: Aug 2004
Location: Melbourne - Australia
Bikes:
Posts: 2,096
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I'll also mention i'm quite light! I also tend to run a lower pressure by 5psi in the front then in the back.
blue_neon is offline   Reply With Quote
Old 09-02-06, 11:32 AM   #17
ScareyH22A
Noob
 
ScareyH22A's Avatar
 
Join Date: Apr 2006
Location: Orange County, CA
Bikes: '06 Trek 8500
Posts: 119
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
My 5000lb truck recommends 35 psi and my 2900lb coupe recommends 35 psi. I don't get it.
ScareyH22A is offline   Reply With Quote
Old 09-02-06, 12:24 PM   #18
Paniolo
Senior Member
 
Join Date: Jul 2004
Location: N Dallas, TX
Bikes:
Posts: 830
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
The size of the tire makes a big difference for autos/trucks ...same would also apply for your bike. On my 4000# 4x4 I run under 15psi in the rocks on 36" tires. otoh to tow 6500# I need 85 psi or so.

On my Rockhopper with 2.2" tires I run 35-40 rear and 5# less in the front. For rocks, roots and general rough stuff the lower the pressure the better the traction ... offset by avoiding pinch flats. For faster dirt trails higher pressure will be faster. You need to experiment and find what works best for your weight, trail conditions and riding style.
Paniolo is offline   Reply With Quote
Old 09-02-06, 09:11 PM   #19
Jason222
Banned.
 
Jason222's Avatar
 
Join Date: Nov 2004
Location: Moncton NB
Bikes: Trek Jack...trials bike soon.
Posts: 2,123
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I ride 25-32 rear and 55-65 front.
Jason222 is offline   Reply With Quote
Old 09-02-06, 09:27 PM   #20
Namenda
.
 
Namenda's Avatar
 
Join Date: Jul 2005
Location: "The Woo", MA
Bikes:
Posts: 4,830
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
45-50 for street, 35-40 for trails.
Namenda is offline   Reply With Quote
Old 09-03-06, 12:24 AM   #21
hardrockrider
Newbie
 
Join Date: Jul 2006
Location: Seattle, WA
Bikes: 2005 Specialized HardRock Pro Disk
Posts: 1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I mostly ride on the street and run 80psi front and back(max on the tires). I ride like that on trails too but sometimes air down if i need more grip. Higher pressure=lower resistance=less work.
hardrockrider is offline   Reply With Quote
Old 09-03-06, 12:43 AM   #22
Jason222
Banned.
 
Jason222's Avatar
 
Join Date: Nov 2004
Location: Moncton NB
Bikes: Trek Jack...trials bike soon.
Posts: 2,123
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You roll a lot faster with a higher PSI and it's easier to pedal. But on the downside, you lose grip.
Jason222 is offline   Reply With Quote
Old 09-03-06, 05:15 AM   #23
Dr Game
Junior Member
 
Dr Game's Avatar
 
Join Date: Aug 2006
Location: Ottawa Canada
Bikes:
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
it depends more or less on the tires.. width... and what they can handle
Dr Game 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 04:15 PM.