Tire pressures: do you trust a floor pump?

Figured its time i start gaining more experience jiggling with my tire pressure. Today for my ride i figured “30 is a good number to try”. Tires were already at a “ridable but soft”… more on the harder side of soft. Not oh my god this is gonna fall off the sidewalls on the first bump soft.

So I hooked up the floor pump and it read like 10 psi, and i got pumping and i stopped at 30. Thing is tho, the ride was shite and they seemed hard as hell.

Do you trust floor pumps or do you have a secondary guage that you use?

I trust my floor pump (zefal), but I checked it’s accuracy with a separate pressure gauge for the first while when I got it, it was only ever off a couple of psi. I found it more accurate with presta tubes, shraders were always a bit under what the gauge on the pump read.

30 psi should feel pretty soft, On the rigid mtb I ride 35-40psi depending on the tires, on the full suspension I tend to go a bit higher.

[quote=“bent6543”]
On the rigid mtb I ride 35-40psi depending on the tires, on the full suspension I tend to go a bit higher.[/quote]

Wow… that sounds like some high pressure. 35psi in my Nevegals and its as hard as I would ever want.

I use the local auto repair shop pump which is surprisingly accurate … for free! :slight_smile:
Gotta love the country for some things… :smiley:

I don’t fuss on exact pressures, I change my tire pressure all the time depending on the trail conditions and what I’m riding.

But I will say I really like the gauge on our Specialized floor pump, we have their mtb specific high volume Air Tool pump. The gauge reads in 2psi increments and only goes up to about 70 psi so it has a very useful range and is easy to read.

I find my Joe Blow fairly accurate, but I’m a lot like Ryan. Too hard? Let some out. Too soft? Pump it up. Look at it this way. If your ride is awesome at 10 PSI on your pump, just always get to 10 PSI with the same pump. For a while I was running 30 PSI or more in the 29er, but with the big tubeless jobbies, I have been experimenting. I went so low as to squirm, and came back up to where the ride and grip is good, but the tire still has some support for cornering and stuff.

You can get a bike specific pressure gauge that will fit in a pocket protector. :stuck_out_tongue:

I wonder if there is an iPhone adapter that plugs in thru the headphone jack! and an APP where we can all share tire pressures! :slight_smile: I kid.

But yeah, I want something that is exact so i can do more comparisions and once i settle on a number i like, its easier for my brain to remember.

Mec has one for 12 bucks.

I often wonder about tire pressure. I run Nevegals (26 x 2.35) at 28psi, according to my floor pump. These are not tubeless. Everything feels good at that pressure. I hardly ever flat and if I inflate them any higher they feel far too bouncy even on my FS Trek.

I would go for a separate tire gauge in that case. The actual psi is quite subjective as seems to be proven by the posts so far. To get the feel you want the psi could be quite different depending on the tire and what rim width you have. Maybe the diameter matters too? I only have 26" bikes so I don’t know.

With a new model tire I always start high (40 psi) and let air out while on a ride until it feels good, maybe even add air back if I go to low. When I get home I check the pressure to see where it’s at, then just pump it up to that from then on. When I used to own a lot of tires and change them fairly often for the conditions or specific trail I would write the psi inside the tire with a sharpie (red shows up pretty well on black rubber) so i wouldn’t have to remember.

I tend to run narrower tires, 1.95 or 2.2 with pretty thin sidewalls (IRC Mythos, Panaracer Fire XC…) on 25-27mm wide rims. I find them too ‘squirmy’ below 35 psi, like I’m riding flat tires. The profile of the tire (rounded or square) will have an effect too, I find rounded tires feel better with a little more pressure but I like square ones to be able to roll over a bit so there isn’t such a sharp transition from the center knobs to the side knobs.

After my fifth flat front tire in five rides (!!!) I’m questioning the gauge on my floor pump. I had been running about 30 psi but recently have been trying 40 to 45 psi and the flats began soon after. Bought a presta to schrader adapter but my bike is in the shop at the moment (unrelated to the flats – bad freehub) so I haven’t had a chance to check it yet.

To be honest… I lack a lot of experience with many sets of tires and I’m really trying to get more “in tune” with my equipment. Right now I’m not even sure I could pass a blind taste test between one sidewall and the other.

unlucky! Pinch flats or just going flat? If they’re happening in the same spot on the tube every time? I’d check your tire over very carefully inside and out for something stuck in it. I had an issue this spring with a hawthorne stuck in my tire, it had broken off flush inside and out so it felt like nothing was there, but it would push into the tube when riding and puncture pretty quickly, i usually found out the next day, that cost me 2 tubes after the initial flat:(

I trust my floor pump. It is a Filzer floor model. Before buying a pressure gauge why not compare you pump to someone else’s and see. The gauges are really simple devices and should work pretty accurately.

That being said 30 psi is really only applicable to the one tire you are using on that bike. Change the tire dimension, tread pattern etc… and it will ride very differently. Personally I would rather start a ride with a slightly high psi and let a little air out.

I can tell you that once you reach a certain firmness on the tire, there is no way you can feel the right pressure anymore. You need a gauge. But if you like it slightly squishy, you should be able to tell that easily enough.

[quote=“bent6543”]

unlucky! Pinch flats or just going flat?[/quote]

Single pinholes, always on the rim side. Always in a different location relative to the valve stem. My rim tape is fine, everything is clean and I even covered the entire inside of the rim with electrical tape before the last one. I was patching two different tubes because I didn’t have any new ones. I got around to picking up some new ones now so hopefully between that and double checking the pressure I will be fine. If not, I’m going tubeless!

Once you go tubeless, it’s hard to go back…