EricOnHisBike

I've got a set of Giant Crosscut AT2 tires in 700x38 that came on a Giant Revolt 2. They are "Tubeless ready" per the sidewall and indeed are mounted tubeless.
The sidewall indicates a pressure range of 50 - 75 psi. Is that when used with a tube or tubeless?
Surely when run tubeless I can run a lower pressure than 50psi, right?

Thanks,
Eric

veloz

Yes. I have a Revolt, came with those tires and I ran 32f/44r for general conditions. Sometimes lower for extended off-road with sand patches. Be aware the rims are wide (25c) and may exaggerate widths when you replace them.

Badger6

Ignore the sidewall rating...it's a nice suggestion. Measure your tire once inflated with a calipers and then find a pressure calculator to get a much better estimate. Silca has a pretty easy one to use, SRAMs is a lot more detailed. Regardless which one you get, it's an estimate.

Iride01 

Why don't you just ride the bike and figure out what pressure works best for you on your roads and riding conditions?

rumrunn6

got a cheap unit from Harbor Freight & I've used it so many times for bike stuff. really a handy item to have around the tool bench













useful for comparing disk brake pads new vs old. it may not change your mind but it's interesting sometimes just to have a number to think about

rumrunn6

more tires ...






of course a good ruler can be used for rim tape

Bodgeitbob

This makes me think I've been using too much pressure all my life. I just blow em up till there hard to squish. Job done. No guages ere

EricOnHisBike

In the long run that's the plan, but I'll be taking it out for my first real gravel ride and my portable presta gauge is broken. Also I'd prefer to use the floor pump with the working gauge at home to at least start at a reasonable place rather than having to stop and fiddle around with a mini pump repeatedly during the ride.

cxwrench

Obviously (or maybe not) it depends on how much you weight, where you're riding, and how you ride.

Iride01 

When I'm trying to figure out what pressure I need for my tires, I leave them at the selected PSI for the entire ride. I also do at least a dozen rides at that same pressure and then do another dozen at another PSI. Then rinse and repeat until my legs and my data show me what is best for me.

The only time I might adjust it mid ride is if I realized it was too low and I was in danger of pinch flats.

Badger6

facts!

Badger6

That's very sciencey...I'm far too impatient. I know how I like it to feel for a given surface, and I've ridden so much that I can usually set any given tire pretty close, always aiming to overshoot by a little bit. Then I play with it, letting small amounts of air out. Once It feels good, I get out my digital pressure gauge and measure the pressure and write it down. If I was more patient, I'd go your route and work averages.

Iride01 

Yeah.

I used to do like you say, but when everyone started telling me I was running way to high a PSI in my tires, I wanted to find out if they were right or not. Turns out I was right. And I've done this seemingly long process at least three different times due to changing tire brands or size.

Badger6

I tend towards too soft on dirt, so this led me to dialing it in. I'm still pretty "high" relatively speaking on the road.

rumrunn6

after I got a 29er style mountain bike, I started reading what others were writing about that "species" incl. tubeless. then I read one person write something like this: "I run mine as low as possible until I get a pinch flat, then increase the pressure until I stop getting flats" (literal or figurative, I don't know) (granted, these may be wider tires that the OP) but anyway, I started playing with real low pressures, especially on softer ground. it's been a fun cpl years, getting to where I know what I want, where

Sardines

Yeah pressures have always been a difficult thing. The variables on the physics is complex, yet apparently so easy. Yet when I changed to the Schwalbe Addix tour compound for the Marathon Supremes, riding at the same pressures, I suddenly felt pain in the back of my left knee for the first time in my life. Bringing the pressure up 10psi, and the pain was gone! Drop it again on a hill climb, and it was back! Still trying to mess with it to see what is going on!