mojofelix

I have three upright bike tire pumps. The one I usually use is Blackburn Airtower 3 on my Presta valves.

Years ago, when I had Topeak, I trusted the gauge inflating to 160 psi and it was fine. I don't trust the gauge on any of my current pumps in inflating to 145 psi. So I go by feel.

Do any of you...

Trust the gauge?
Not trust the gauge?
Go by feel?
Use a separate gauge?

What works for you in inflating to high pressures?

WhyFi

Low is the new fast, bruh.

Seriously, though - it boggles my mind to think that someone runs these pressures on the road.

Doge

We guess what is our ideal pressure. It is generally based on feel and what we like. What we need is a way to reproduce it. So if the pump was precise and said A, B or C for pressure, that would be fine if you liked it at B.
So if it says 110PSI even thought it is 90PSI, but you use the same pump all the time, I don't see the issue.

But ultimately, you decide what works best for you. Having a tool that gives you constant (precise) readings is more important than an accurate less precise tool.

So readings of 110, 109, 108, 110 when it is really 90 is better than readings of 95, 85, 94 when it is really 90. You need something repeatable.

Princess_Allez

I inflate with my Lezyne floor pump and adjust with a separate gauge. My floor pump reads ~6-10psi more than my JACO gauge (purchased thru Amazon).

Ghazmh

Trust, no. Use it as a point of reference to keep the tire pressure consistent, yes. If 90 PSI on the gauge feels good to me and it’s really 72 PSI than so be it.

Bah Humbug

According to Silca (and Flo), pump gauges are crazy inaccurate. The one on my Spesh AirTool Comp seems to be accurate, so I do wonder if it's the TopPeak, Blackburn, JoeBlow, and other general brands that have issues. Honestly, I've found most other pumps to be terrible in general.

biker128pedal

Tried low in 23mm tires (95 psig) but get pinch flats. 25mm rubs in 2006 frame. Run what is appropriate.

To answer the OP I have found floor pumps to be off and use a hand gauge. Bontragger read is 5 psig high.

MagicHour

I just go by whatever it says on gauge (an original Silca and Nashbar pumps) and leave it at that based on ride feel and infrequency of flats. I also usually compensate a little over for the bleed that occurs when popping chuck off valve. One of these days, if I stumble across an inexpensive/reliable pressure gauge I should check it, but it's one of those things if its not broken then I don't try fix it.

Years ago I'd ride 700x23 @105psi or so, nowadays its 700x 25 or 28s @ 95psi and less (i'm ~160#).

woodcraft

Seems like telling the difference between a 145 psi tire and something close

would be like telling brick and concrete apart by which one feels harder.


I find that just how you take the pump head off can vary the pressure quite a bit.

Kimmo 

I have a Bontrager floor pump that was way off, like 20psi. Hacked in a proper certified gauge I got from work. Aah.

znomit

Weigh bike -> Pounds.
Paint tyres with ink.
Put bike down gently on paper.
Measure area of ink blotches -> Square inches.
Divide Pounds by square inches.

79pmooney

Are you using presta valves? If yes, all the air you hear is coming from the pump, not the tube. The presta valve shuts off instantly when outside (pumpside) pressure goes below tube pressure. But all that air in the pump is still compressed and bleeds out the chuck. Granted, I am assuming you are not "leaning" on the valve stem and nut with the chuck as you pull it off. Easiest way to avoid that is to strike the pump chuck sharply with your hand in line (like a gentle karate chop) in line with the valve. (Schraeder valves do not pull off nearly as cleanly and can lose a lot of tubeside air.)

Does anyone here take their pumps to their LBS and ask them to compare it to a pump or gauge that has been calibrated? I would expect any good LBS to have one that is close.

Ben

MagicHour

Yes Presta - you are probably correct about the pump decompressing bleed, never thought about it. Anyway it's moreso with my Nashbar chuck which has a sort of dual mode lever lock that seems to release a fair amount of air, than the traditional Silca that just pops off with a "fwuppp".

Racing Dan

If you use the same pump every time, soon you figure out what "number" fells right to you. It may not reflect the actual pressure but its not that important imo. What IS important is consistency of the gauge, easy operation of the pump and pump head, a long flexible hose, ect.

I have found that the reading on the gauge can fluctuate some related to the "pump speed". The harder/faster I pump the higher the reading. Try one hard stroke and the gauge will jump. For that reason I always pump with low intensity for the last few strokes. I believe that will ensure more consistent readings.

JohnJ80

Agree. I have several pumps, none of them agree or tend to be all that repeatable. I use a Silca pump and I am able to reliably pump my tires back to the pressure that I've found works best. On 30c tires, the "sweet spot" tends to be about 3-5 psi wide for me which was less than the variance in pumps (around 10psi between my different pumps). The two silca pumps I have agree and agree reliably with each other.