Ride what works for you, not anyone else. Drop the PSI, if you pinch then pump it back up a bit.

 

I appreciate your response, but it's not very helpful. I understand the principle, which is why I keep trying new pressures, it's just slow going and I'm trying to get a feel for the baseline.

 

I can't run under 30psi in the rear or I'm bashing my rim. I weigh 210lbs and ride fairly aggressive with lots of rocks. Stans flow ex rims with maxxis exo tires.

 

Agree it will be some trail and error. The amount of pressure you can run is largely based on how you ride, your weight, and the tire volumn. Even at the same weight, someone running 2.2 tires will run more pressure than someone running 2.4's. So you would literally have to find someone with a similar weight and same tires on same width rims to get some good feedback.

 

I am also in the 30+ psi camp. Lots of rocks where I ride, and I also don't like the feel of squishy tires. I rode for a few rides at 20-25 psi, and just didn't like the feel. Also had a front tire burp at 20 psi. I haven't had a flat or a burp since going back to 30.

Good luck.

 

With rims that narrow and tires that wide, I'd guess squirm is going to limit you before rim strikes or pinch/burping. I can't even imagine running a 2.4" tire on a rim as narrow as a crest - last time I tried was 15 years ago and I needed to run 40 psi to keep any sort of traction in corners.

probably 90% of riders end up in the mid 20s in front and around 30 in back, that's what I'd call baseline. It depends on a number of things, and I'm guessing your terrain tolerates low pressure better than somewhere rocky. If you want to know do like tooTall said and keep lowering till it's too low. If you want to guess high 20s-30 is an ok start.

 

FL? Big roots? Here in New England we have rocks and roots. I run 28 front and 30 rear for psi. 29er x 2.3's. 235 lbs, I ride with clothes though Full suspension, crash and burn type riding. Start where you are, drop 2 psi at a time. No one rides just like you, with your riding style, bike and trails. Make your own guideline. Or do repeat laps of a "good trail" and change the pressure every lap. Or (sorry here) just move so you don't ride in sand and mangrove swamps?

 

FL? Big roots? Here in New England we have rocks and roots. I run 28 front and 30 rear for psi. 29er x 2.3's. 235 lbs, I ride with clothes though Full suspension, crash and burn type riding. Start where you are, drop 2 psi at a time. No one rides just like you, with your riding style, bike and trails. Make your own guideline. Or do repeat laps of a "good trail" and change the pressure every lap. Or (sorry here) just move so you don't ride in sand and mangrove swamps?

Yep , believe it or not we have roots and lime rock , abandon rock quarries and phosphate mines...
For what it's worth OP , I run tubes, and 35 in the front and 38 in the back. Alafia , Santos , etc. etc. 29er hardtail , race kings protection , 270 lb geared up. I'll be setting them up tubless in the near future. I tend to run a little more psi than most ppl , mainly because I don't want to ding my expensive wheels.

 

I ride in New England custom hardtail with a pike up front maxxis ardent tires 2.4 and weigh 230# with clothes on. Add water and gear probably around 240#. running 25 up front and just under 30 in the back.

 

I ride in New England with 2.35 Nobby Nics and run 18 psi front and 21 rear. I weigh 245 lbs. It all depends on your tires. That is the main factor that dictates your pressure. Drop the pressure to about 15 psi and start riding. Have a pump handy, do a loop ride from your car or home. Keep pumping them up till they feel right, or don't feel wrong. Its a bit subjective, but you will know when you feel comfortable. After that you can do fine tuning by going a little higher or lower depending on the terrain. I bump up my tires if I am riding really fast trails or really rocky trails. I would rather keep the pressure low in the rocky stuff, but I don't want to pinch flat or dent a rim. Don't be afraid to vary the pressure on a short loop ride and figure out the range that works for you and your tires.

 

Running 29x2.3 DHR2's front and rear right now. 22psi front/26psi rear on Roval Fattie SL wheels. When I ran a 29x2.5 DHF up front I ran it at 18psi.

I'm 235 +/- 5lbs before gear. The only flat I've had in the last 2 years with this setup is a slice from a sharp rock.

 

Great responses, all. Thank you! Sounds like I'm in the ballpark, so I'll keep tinkering.

 

I'm 235 geared up, and I typically run 26/28 or 27/28 on my bike, but I could go a bit lower if I was willing to lose some rolling resistance. 27.5 x 2.2 with stiff geax tnt sidewalls though. A floppier tire might need another pound or two.

 

I'm 210lbs geared up on a full suspension 29er, with Easton Heist 24 wheels and WTB TrailBoss 2.25 TCS tires. I live and ride in the high desert of SoCal, where rocks areas plentiful as oxygen.

I don't care for the low psi feeling, and the only thing I like less is worrying about smashing my wheels on a rock........ So for me, it's 28/34.

 

Wow, you guys run squishy tires! LOL I'm 220-225lbs, have 2.3's (I think) and I regularly run 40psi front and rear. Too hard? Maybe...but I've ridden tons of rocks 'n roots at 40psi and I don't have a problem. (And I like to roll fast!) Tubeless too, and I've never had a flat nor a burp. Not once since going tubeless.

I once heard someone say that you can/should run higher pressures on a FS bike—because the suspension is what softens the bumps—not your tires. Not sure if that's really true, but it made sense to me. And I don't typically have traction issues...though that's possible because I don't ride in loose stuff much, if ever...and I also don't try to rail corners at high speeds.

Scott

 

I run about 40-45 front and rear sitting at about 320. Anything lower and it just feels too soft in corners. I tried running lower pressures last night and took a hard drop in a corner and washed out pretty good, at normal pressures I've taken that area faster and soared through it without any issues. I was washing out all over the place with the lower pressure. I do run a FS bike, and have heard I can run tires higher without pinch flats etc, and I haven't had any issues there either. The northern part of my home trail is fully of rocky drops and rock gardens, with Spec Control Renegade tires, no sidewall problems.

 

At 220lbs, I'm surprised you're riding crest rims. I'd be afraid to ride those. I'm about 235lbs out the shower, and on some 2.1" tires, I run 28/32 psi. On 2.3" up front, I'm about 24-25psi, and 2.2" in back I normally run about 28-30psi. Also depends on what I'm riding. rocks & roots get more to prevent pinchflat, fast corners get more because I don't want to roll the tire off the rim.

I think you're tire pressure will be limited based on rolling the tire on those crest rims. find an open road/parking lot, lower the rear tires pressure and take a turn at the speed you'll probably end up at on the trail. Once you feel the tire squirm under you in the turn, take the pressure back up 2 psi. Drop the front tire's pressure about 4 psi below the rear tire.

 

At 220lbs, I'm surprised you're riding crest rims. I'd be afraid to ride those.

I'm surprised, too. I'd like to get some Flows, but these came on the bike when I bought it so I figured I'd give them a shot. They've held up, but I'm also not hitting drop drops or jumps.

 

30 psi seems to be the sweet spot for me at 260lbs running Maxxis Ardent 2.25's These are on trails in Scottsdale AZ with lots of rocks and loose dirt. Seems to be the best combo for traction and speed. 34 psi felt too loose and 26 psi felt...weird...

 

As a reference for all you 30-40+ psi weirdos, I'm 330 lbs and ride in a lot of rocks. I run 25 psi front in an ardent 2.4 and 30-32 psi rear on a 2.3 spec grnd control grid. Heavier tires with thicker sidewalls/more protection can be run lower. This is tubeless but I rarely ding a rim. Go as low as you can without pinching or dinging, otherwise you are losing out on a lot of performance and comfort.

 

Im 260 and im running tubed. Butcher and gc. I find it slippery 35+ psi. Not grippy at all. Got a slow leak from it but felt good around 30psi. Thinking about tubless and 28/30 psi this summer might be the key. Possibly drop that heavy butcher as well as i have another gc

 

I'm 245 and ride a rigid singlespeed with a fat front. 17 psi front, 24-26 rear on a 2.4 ardent. Lots of rocks. Tublesss of course.

 

This is where I'm starting to settle in at, I think.

I switched my rims to wider Flows, and picked up a full suspension bike. I'm at around 15 psi in the front and 20 psi in the rear right now.

 

Me: 220 geared-up
Bike: 27.5 full-squish (2.3" tires on i23 rims)
Pressure: 25 front / 30 rear

On my tubeless-equipped gravel/commute rig I run 700x40 @ 30 front / 40 rear

 

Me: 240 lbs with gear

Bike: Hardtail 29er, 2.2s
PSI: 21 front, 26 rear

Bike: FS 29er
PSI: 21 front, 26 rear is working there too.

 

185lbs 15 front 18 rear on very rooty black dirt trail with no rocks. Any more and and I lose control, speed and comfort.

 

I know this is all subjective but it is nice to see what others are running. So I thought I'd throw my 2 cents out here.

I'm 6'5" 250 pounds. before gear. My new tire setup as of last night is:

Maxxis Minion DHR II 27.5" Tire 27.5X2.3" 3C/Exo/Tr, F60

Maxxis Minion DHF WT 27.5"X2.5" Tire 27.5X2.50WT, 3C Maxxterra/Exo/ Tubeless

Today I ran 30 - 35 PSI to both tires to get a feel, both tubliss of course. From my experience, 30 is a pretty good starting number for almost any Tubliss MTB tire.

Today was the first ride with only 10 miles total, and about 1700 feet in elevation gain. I have to say on these tires are amazing!!! when going Uphill, I had both set at 35 PSI and down hill, both at 30. The tires hook up great and I had a enormous boost in confidence today. The uphill felt great and seemed to roll well, That was a worry of mine stepping up to such an aggressive tire, The downhill felt so smooth, It felt as thought the tires were just soaking up the hits. Maybe thats due to the big 2.5 Front.Cornering felt smooth, But from first ride, I think I should air down more for the downs.

For my next ride, I will decrease the front to 27-28 and the rear I'll keep at 30 PSI.

 

I know this is all subjective but it is nice to see what others are running. So I thought I'd throw my 2 cents out here.

I'm 6'5" 250 pounds. before gear. My new tire setup as of last night is:

Maxxis Minion DHR II 27.5" Tire 27.5X2.3" 3C/Exo/Tr, F60

Maxxis Minion DHF WT 27.5"X2.5" Tire 27.5X2.50WT, 3C Maxxterra/Exo/ Tubeless

Today I ran 30 - 35 PSI to both tires to get a feel, both tubliss of course. From my experience, 30 is a pretty good starting number for almost any Tubliss MTB tire.

Today was the first ride with only 10 miles total, and about 1700 feet in elevation gain. I have to say on these tires are amazing!!! when going Uphill, I had both set at 35 PSI and down hill, both at 30. The tires hook up great and I had a enormous boost in confidence today. The uphill felt great and seemed to roll well, That was a worry of mine stepping up to such an aggressive tire, The downhill felt so smooth, It felt as thought the tires were just soaking up the hits. Maybe thats due to the big 2.5 Front.Cornering felt smooth, But from first ride, I think I should air down more for the downs.

For my next ride, I will decrease the front to 27-28 and the rear I'll keep at 30 PSI.

Interesting. I'm running the same setup. And can't find a magic number for my rear tire. It either squirms and flexes for squishes to the point I'm afraid for my rims.

 

250.

2.1 ground contol front 33 psi
2.0 fast track rear 35 psi.

Any less and she gets slippery

 

I switched to Schwalbe Rocket Ron 2.25s and am running 21 psi in the front and 25 psi in the rear. My weight, fully loaded, is about 240lbs right now.

 

You are exactly where I am on a set of Ground Controls right now. I have the standard casing in the front and the GRID casing in the rear, and both are 29 x 2.30. I've tried to run 30 in the front and 40 in the rear and I bounced everywhere. Then I went to 25 in the front and 30 in the rear and the front was still too bouncy and the rear was almost there. I'm now 20-21 in the front and 25-26 in the rear and it's perfect. Plenty of grip and I'm just as fast as I was with higher pressure, because I have more grip in the turns now to come in at a higher rate of speed.

I'm on a set of DT Swiss ex471's, so I have a bit more ID then I did on my prior set of Easton EA70 wheels that only had 19mm ID. I had to air those tires of hard, because if I ran lower pressures they would squirm too much. I tended to always have those aired up to 30psi front and 40psi rear.