# How low is to low for tubeless PSI?



## dirtyknobbies (Apr 19, 2011)

I converted to tubeless two rides ago. My ride today didn't fair so well. Running DT FR600 Rims, W/ Stan's Conversion...no issues there. Where the issue lies is..... took off the Schwalbe Big Betty's and Mud Mary ( First Mistake right there!) and put on some Panaracer Cedric Tires. Hey the idea was to loose some rolling weight and go to a cheaper priced tire..this is on my AM bike.

Anyhow running a wonderful 21 PSI, drifting corners, loving it...and POP..hit a nice rock. Fell the coolness of Stan's on my legs. Oh maybe the tire just burped. Nope...put a huge hole right in the middle of the tire. Brand new, not even 50 miles on it. Tire done. 

Sooooooooooo first thing I am doing is going back to my Schwalbs. But hey for all you tubeless freaks out there....what is to low of PSI before any tire just becomes rock fodder? I weigh high 170's with riding gear on.

Cheers


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## darth biker (Jul 8, 2011)

go 25psi on tubeless to be safe


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## kenbentit (Jan 2, 2003)

I usually stay above 25 too. Any lower and I have to worry about cuts and bashing the rim, not to mention the possibility of burping the tire. Some tires are a bit softer so it can vary a bit. I also tend to run about 5 psi more in the rear tire than the front....


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## dirtyknobbies (Apr 19, 2011)

Good to know. I was running around 30 PSI with tubes, so thought I could go lower. But yeah ended up damaging the rim a bit..nothing a file can't fix. The CG tires are rated as 35 PSI min. So was wondering how they would handle. Guess I know now!


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## Lelandjt (Feb 22, 2008)

Less than 30psi front, 33/34psi rear and I dent rims. This goes for all my bikes/tires.


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## SHIVER ME TIMBERS (Jan 12, 2004)

honestly...you don't have to run low tire pressures....tubeless you can run highwer pressure but still get traction like a tire with low pressure running tubes....your am tire was too thin or defective

FYI Big Betty's are light tires


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## DHgnaR (Feb 20, 2008)

Cutting your tire open on a rock will happen regardless of PSI. I've done it to a brand spankin new minion at 30 something PSI. The tires not done though, just put some duct tape on the inside where you punctured, and run a tube. No use wasting a new tire.


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## 2clue (Jun 9, 2007)

That's actually just the CG...I have gone through 3 CG in less then a 100 miles total. All of them had cuts right down the middle of the tread about a cm long. First one for me cut at 23-25psi....second one cut at 30psi....third one cut at 32psi..... I now run Conti's..with tubes......cause even with those I still cut them at 30-35psi.


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## CaveGiant (Aug 21, 2007)

in response to the OP it depends SO much on the tyre/rim/riding style.

I have run as low as 8 psi, and to me that is the absolute lower limit.

I am normally ~20 on front 25 on back.

I run 2.5" tyres (various WTB), and 47mm wide rims.


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## leggatt (Oct 8, 2005)

You guys running close to 20 PSI must love a really crappy handling ride. That is too low pressure with or with out tubes, especially with standard tires running tubless.

The tires roll excessively and really compromise the handling and also the safety of the tire. Way to easy to burp or roll the tire off the bead.

I run about 28-32 on the back and about 28-30 on the front. Lower than this really doesn't feel good.


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## clockwork (Dec 9, 2006)

Really it truly boils down to what you are riding at the time and how hard/fast you ride.There are many other factors to affect pressures people run at . Rim/tire bead interface..dual or single ply ect.

But for me and my terrain/riding style I find 27-30psi front and rear 28-32psi works great for me . I have also ridden with pressures as low as 20 but that wasn't on a dh/fr trail


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## leggatt (Oct 8, 2005)

clockwork said:


> Really it truly boils down to what you are riding at the time and how hard/fast you ride.There are many other factors to affect pressures people run at . Rim/tire bead interface..dual or single ply ect.
> 
> But for me and my terrain/riding style I find 27-30psi front and rear 28-32psi works great for me . I have also ridden with pressures as low as 20 but that wasn't on a dh/fr trail


I have run really low PSI but only on DH casing tires that are 2.5 size. Even then it is a very squirmy ride, whether that is in berms (lot's of roll) and tech sections (again, more roll).

There may be more traction but at the sacrifice of stability and control.


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## Gman086 (Jul 4, 2004)

Depends on rider weight... 
Lightweights can get away with 20 psi
Middleweights 25 psi (where I'm at)
Heavyweights 30 psi

Any lower and you'll dent/crack rims.

Have FUN!

G MAN


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## dirtyknobbies (Apr 19, 2011)

I dunno. Like I said before I would run 30 psi with tubes and never have had issues with flats, but found traction to be well, not to my satisfaction. The whole tubeless was to run a bit lower PSI, get into the 20's. According to Stan's with my weight I should run 24 PSI in the front and 27 in the rear. Put the Schwalbes back on today and set the rear at 27 PSI, front at 25 PSI and wow, much better ride then 30 PSI w/ Tubes. My first attempt yeah I went too low, but figure there is a learning curve here when running in the 20's for PSI. 

I live in AZ and most of my riding is over super chunky rock going up and down. I found running the low PSI I can clear super tech sections much cleaner, and seems to handle the rocks better going down the trail. Low 20's is obviously too low for me. But yeah...would want to run at least 30 PSI for the hard pack buffed out bermed trails.


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## kenbentit (Jan 2, 2003)

Tubeless at the pumptrack is a ton of fun BTW. Nothing beats blowing a tire off the rim in a tight berm


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## leggatt (Oct 8, 2005)

kenbentit said:


> Tubeless at the pumptrack is a ton of fun BTW. Nothing beats blowing a tire off the rim in a tight berm


Exactly! Did it just the other day. Was running a rear fat Albert low just to give it a whirl and easily rolled the tire. I wouldn't go below 25PSI ever, especially if raailing berms.


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## noose (Feb 11, 2004)

I am going tubeless next week but if I can't run in the low 20's psi without burping or coming off the rim I will be going back to tubes. Traction means more to me than puncture protection as there are no sharp rocks or thorns on my trails. 

Sent from my SAMSUNG-SGH-I337 using Tapatalk


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## Gman086 (Jul 4, 2004)

Uhm... tires and rims have evolved a little bit in THE PAST FIVE YEARS!!! Holy Easter thread Batman!

Have FUN!

G MAN


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## riding4life (Jun 4, 2013)

Gman086 said:


> Uhm... tires and rims have evolved a little bit in THE PAST FIVE YEARS!!! Holy Easter thread Batman!
> 
> Have FUN!
> 
> G MAN


LOL, I'm sitting in the office, bored out of my mind, and your post made my day. I've been up since 5 AM this morning and Seriously your post gave me my first laugh of the day. FIVE YEARS!!! lmao


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## noose (Feb 11, 2004)

So if I create a new thread I get flamed but can't post on an old one lol. 

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## Haint (Jan 25, 2012)

noose said:


> So if I create a new thread I get flamed but can't post on an old one lol.
> 
> Sent from my SAMSUNG-SGH-I337 using Tapatalk


A five year old thread having bad grammatical context in the title does not work in your favor.

Or, does it??


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## Haint (Jan 25, 2012)

Flucod said:


> Lighten up Francis, anywho, what stem size you guys using?


That thread made the Dead Meadow for a reason.

I took the stem off my bike.


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## riding4life (Jun 4, 2013)

Flucod said:


> Nice! I have been looking for a reverse stem to try to get my bars 5 inches behind the steerer and would like a bike with a 31 inch top tube to do it. Also on the tubeless note, really want to find a set of DH tires that can run below 3 psi.


I just use solid rubber tires, haven't burped, puncture or rolled off the rim in years!!! I usually switch between these two depending on terrain. The left pic is my XC tire and the right is my DH/Freeride tire.


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## bpressnall (Aug 25, 2006)

Stans has a formula for their rims: Rider weight (I assume with gear) divided by 7.
Subtract 1 lb. for front tire and add 2 lb for rear.
Example 175 divided by 7= 25, so 24 lb front and 27 lb rear.
Then fine tune from there. If you still burp, you might have to go a bit higher. Stans have a little bit of a bead to help keep the tire from coming off and some tires roll off easier than others. Also, wider rims are less likely to get the burp.


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## bpressnall (Aug 25, 2006)

Ha, I just noticed this thread is five years old. I imagine he's figured it all out by now!


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## NWS (Jun 30, 2010)

Do you folks who run ~25psi up front ever feel the tire squirm when going up the lips of jumps, or when landing?

It freaks me out when that happens so I stay at 30psi up front just to make sure that it never happens. I'm still running tubes though, and this thread has me wondering if tubeless is less prone to that problem.


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## aerius (Nov 20, 2010)

NWS said:


> Do you folks who run ~25psi up front ever feel the tire squirm when going up the lips of jumps, or when landing?
> 
> It freaks me out when that happens so I stay at 30psi up front just to make sure that it never happens. I'm still running tubes though, and this thread has me wondering if tubeless is less prone to that problem.


Tubeless is actually MORE prone to tire squirm at a given pressure. With a tubed tire, the tube helps stiffen up and support the tire, with no tubes, the tire is more supple with less support which helps it conform to the ground better and aids traction, but it also means there's more tire squirm. I actually run more pressure in my tubeless setups to keep my rims from getting bashed to pieces and also to keep the tire from burping or rolling off the rim when subjected to heavy loads.


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## noose (Feb 11, 2004)

Good point. I am running the same pressure as I did with tubes but had much thinner sidewall tires previously. 

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## NWS (Jun 30, 2010)

Thanks for clearing that up. I'll be keeping my tubes then. Traction is basically a non-issue for how/where I ride anyway.


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