I weigh about 185 lb and run:
Road: 30mm Vittoria Corsa Control TL @ ~58 PSI
MTB: 2.25 Vittoria Mezcal Tubeless @ ~18 PSI
For road I started with some chart online then kinda kept going down till it felt a little squishy or squirmy in the corners.
For MTB I did something similar but until I felt I only got one or 2 rim strikes on our local rocky/roots XC course.
All just starting points really …
MTB - I use the Stans formula: pressure in PSI = weight in pounds/14 then -1 for front, +2 for rear.
Fat Bike - weight in kg/10 then -0.5psi for front, +0.5psi for rear. (this assumes reasonably firm terrain, once I get on soft snow I may be as low as 2psi!)
Road - about 90psi or if the bike starts to squirm in bends add a bit 
Scottish people Twitter is one of the all time great subreddits
So related, how does everyone check their pressure? Track pump gauge or dedicated pressure gauge?
I just, like, squeeze the tire, man 
Road: firm-ish, with a very slight give (28mm tubeless). When it seems low, I pump it up to 75psi. Usually the 40s when it fails the squeeze test and I attach the pump.
CX: lots of give, but not so much I can press all the way down to the rim. Start at 30psi and work down depending on the course (and don’t even get me started on tire selection).
Works for me. Maybe not for you if you don’t weigh the same or have the same grip strength
Digital pump. Silca digital gauge reads the same a hand gauge I verify with, so for most rides I pump up with the Silca and that’s it. https://silca.cc/products/superpista-digital
Topeak Smartgauge D2 (hand gauge). If I need to check tire pressure at some point, the Topeak gauge works great. SMARTGAUGE D2 | Topeak
Quarq TireWiz. Just recently got a good deal on these so decided to get them. I was curious to see how much my tire pressure changes on long rides, especially with the recent hot conditions. I also will bring them along next time I head out west. There was a good thread where we were discussion tire pressure in the mountains with effects of temp and altitude changes. These will allow for some monitoring to better see the live impact of these factors. Also, I had thought for some reason that the retail was $199 each, but there are two of them in a pack. Still expensive at full retail. Quarq TyreWiz | WH-TRWZ-A1 | Quarq
Yeah, the Silca digital is on of the few pumps that is pretty accurate with its onboard gauge.
My town bike (Flat bar road school pickup bike) the other week. Got 100m down the road and felt what I think was the rims bottoming out on the road.
Thought geez I must have left that a bit long between topping up. Luckily it turned out to be a slow leak/old tube.
Thanks for contributing to this thread! I love Silca products. No question.
But a few points regarding the accuracy of that pump. First the accuracy is specced at 1%, which is great, but what does it mean? It means 1% of full scale, which in this case is 220psi. So +/- 2.2psi.
Consider Topeaks Joe Blow digital pump. It’s specced at an accuracy of 1psi for pressures below 100psi & 1% for pressures above 100psi. If accuracy is what you’re after in a pump you can save yourself abou $120 bucks here.
Most gauges spec accuracy as a % of full scale so you’re better off buying a gauge that is specced at a lower pressure. Personally I have a stand alone gauge that is specced to 60psi and +/- 0.5psi. I use that as a calibration tool for my gravel tire/pump. That’s where it really matters to me if I have 38psi in the tire or 40psi. I used an awl to scratch the desired pressure on the dial of my bike pump. The bike pump seems to be repeatable just not accurate.
That way I can use a $40 pump and a $20 gauge to do the work of a $130 pump/digital gauge. Actually, the $60 solution is better than the Joe Blow pump because it’s way more accurate.
This has been one rider’s opinion…
I actually have a Joe Blow, one of my favorite all time pumps. But in testing the accuracy has been show to be more in the 5% range. I don’t have time to go look up links right now, but the data is out there somewhere
I have an early 2000s edition of that pump still going strong.
But yea, the pressure gage on that thing sure does blow. 5% sounds about right, as in it’s always off by 5% at least (reads low).
Yep. Joe Blow Pro is +/-2% of full scale, which is 200psi. So +/-4psi. I’m not surprised that you might see ~4% difference at or around 100psi.
Is that what you have? Just a regular dial gauge? The Joe Blow digital is specced at +/- 1psi for pressures at or below 100psi. If you’re using the Topeak Joe Blow digital and getting 5% error I’d get that thing warrantied! That’s an expensive bit of kit to be so far out of spec.
Mountain Bike
I generally go as low as I can to where I don’t get rim strikes and the tire doesn’t squirm/fold in corners. Typically the front ends up being 1 to 2 psi lower than the rear. Pressures may change slightly depending on the trail.
I use the same gauge every time. Gauges can really vary, so it’s important to always use the same gauge.
I check pressure before every ride. On larger 2.6" to 3" tires, even 1/2 psi can make a significant difference.
My wife and I have a lot of bikes and I like to try different tire combos. I have a spreadsheet with the various tires and pressures I found through testing. It’s very useful if I haven’t been on a specific bike in several months for example.
Foos yer doos min
i’ve just gone lower and lower and the experience has got better and better.
75Kg. Tubeless Conti 5000: 25F @ 70PSI, 28R @ 65 PSI
fast, smooth, grippy. 
Here’s what I come up with…
SRAM: Front 87.9psi, Rear 93.5psi
Silca: Front 93.5psi, Rear 96psi
Enve: 101psi
So if I have a regular floor pump with a dial gauge specced at +/-2% of 160psi full scale…probably shoot for somewhere between 90psi and 95psi for my 18.5lb bike with 23mm tires & firecrest 404s. Depending on the road surface. 
That’s what I was already doing. Science and ‘rule of thumb’ converge.
GCN’s recommendation always worked for me since I’m a similar weight.
In a more recent video they recommended upping tire pressure 5 PSI if you know the surface is very well paved.
Hey y‘all, a topic near and dear to my heart.
My problem is: I know all the science and all the arguments for generally lower tire pressure. (Thanks marginal gains podcast).
BUT: I hate getting flats. Lower pressures may be fine when you are racing for optimal performance (and maybe have a mechanic with you).
So, for the fear of pinch punctures I most of the time run as high a pressure as is allowed, or close to it: That‘s 8 bar (115psi) for my 25mm road clinchers and 7 bar (100) for my 32mm „rough surface tires“. (I’m 72kg/158lbs).
And then I complain about the rough ride…
Anyone here that can help me overcome my pinch-flattening fear?
Learn to unweight the bike to roll over stuff that causes you to pinch puncture. Oh and go tubeless.
(Road Bike)
My weight+10+10 works perfectly
88kg+10psi+10psi(contingency 
). I complete it to 110 and off to go. Saw it on GCN
