# downhill tire pressure value



## Dunc (Jun 9, 2005)

I'm new to the big bikes and wondering what pressure to run. Sidewall on the minions and others say 35lbs and up. This seems pretty firm? Seeing flatspots and rim dents on other rims, does this happen at 35lbs? Is it ok to go lower depending on terrain or are you risking peeling the tire of the rim or banging it up. eg. setup Mag 30 with 2.7 minion running 35lbs. Looking for a starting point or some idea where the flats and damage begin.


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## RYAN E (Jan 11, 2006)

I usually run between 30-35 psi for local rocky loose trails


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## clockwork (Dec 9, 2006)

I run 2.5 minion 3c's tubless/823's with 27-32 depending on terrain . Most of the time @27. I have slammed some serious rocks and yet to even knock my 823 out .


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## chooofoojoo (Feb 22, 2007)

Tire pressure is a weird thing. Everyone will have personal preferences. 

I have run anywhere from (literally!) 12/15 psi combo to 35/40 psi combo 

General rule of thumb is to run your rear tire a bit firmer then your front. Most of the time about 30 psi works in varying conditions.


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## tacubaya (Jan 27, 2006)

Fill up your tires with squirrels and rats, it improves traction dramatically and reduces flats.


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## norbar (Jun 5, 2007)

35-40 For rocky stuff while for softer stuff 25-30. Tried <20 but it was to low imo.


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## Gemini2k05 (Apr 19, 2005)

35-40? wow, way too high. If you have 2ply tires, not running them tubeless, 28 tops for rear, 25 tops for front.


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## SHIVER ME TIMBERS (Jan 12, 2004)

first off mag 30's are probably the strongest rim out there....so really no worries

general rule....lower pressure in front for steering grip and higher pressure rear for easier pedaling and more weight is on rear of bike.

for pedaling courses I run 39 in front and 43 rear

*basically if you ran 28 front and 32 rear you will be fine* that is a good overall tire pressure for all terrains


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## Dunc (Jun 9, 2005)

Thanks for the input guys!
About wheel strength....
I also have a set of DT FR6.1d. And yes they already have some dings in them. But would they be fine for the girlfriend at 145lbs? not being supper aggressive.


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## Djponee (Dec 20, 2006)

rockin about 30psi all the time, with wtb speedisc dh rims


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## combatkimura (Jul 17, 2007)

I usually run 28f 32r just about all the time. I tend to keep the back at 32 and mess with the front depending on the conditions. If I'm pedaling alot I might go to a 34f 38r.

Running 2.7 Kenda Telonix Stick-E 2plys.


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## SHIVER ME TIMBERS (Jan 12, 2004)

Dunc said:


> . But would they be fine for the girlfriend at 145lbs? not being supper aggressive.


absolutely....no problems for her at all


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## norbar (Jun 5, 2007)

Gemini2k05 said:


> 35-40? wow, way too high. If you have 2ply tires, not running them tubeless, 28 tops for rear, 25 tops for front.


Really depends on the trail.I maybe overdid it with 40. Max was 36 on my fav rocky trail when it is really a must to run high pressure(some places on the trail that if you don't think before the rockgarden will simply stop you and throw of the bike). After tearing one of my tires there at 29psi I've added extra pressure. Especialy that it's a very fast and rather strait course. I still need to experiment a bit with tire pressures on but tommorow I want it relatively high as it's my first time on Maribor DH track and that nasty rockgarden is really something.


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## 6thElement (Jul 17, 2006)

Had my first legitimate flat in years this weekend (road, xc and dh) when I pinched an IRC DH tube in DH Nevs running at my usual 30psi.


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## Freerydejunky (Sep 21, 2006)

45psi in my 909 2.35 in the back
13psi in my Specialized Big Hit 3.0 in the front

Im a beast


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## tacubaya (Jan 27, 2006)

I just use the squeeze test..


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## chober (Jun 25, 2004)

42 rear 38 front with 2 ply rear and single ply front


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## cesper (Jul 8, 2008)

I used to run 17-20 front and 25ish rear, but I find the faster I get the more air I need. Still no flats in a couple years(knock on wood):thumbsup:


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## Bellafonte (Apr 25, 2008)

25 PSI front and 27 rear Dual ply


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## mrpercussive (Apr 4, 2006)

25psi front and back...


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## Guest (Jul 21, 2008)

Well, all these examples of people's tire pressures are amusing and all but can we get rider weight as well? Just a suggestion. 

Some might say my 22psi/25psi might be on the lower side for rocky, rooty, wet, and hardpack, but then again, I weigh 125 lbs with a full meal and clothed. Tires are Minion 60a dual-ply with Maxxis DH/FR tubes before and ghetto tubeless with Stan's now on TBC Revolution 32s.


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## chuckie108 (Jun 26, 2006)

What a lot of people don't realize is your tire is basically an air spring. The point being different riders, tires, and terrain require different air pressures. I run my 2.5 minions at 35psi front and back, but I'm 220 lbs and ride the expert class. What works for me might be too hard for someone who is slower and or lighter. Your best bet is start with 30 psi and try it out. Go up 2 pounds and ride. Then go down 2 pounds and ride. Eventually you'll find that sweat spot of soft enough for good hook up, but not so soft the tire gets squirmy. There is no magic number, trial and error is your best method. 30 psi is a good place to start.


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