Scorer75

I always inflate my tires the night before I ride, like this when I come down in to the garage in the morning I will know if there is a slow leak and not have to find out on the road. I like my tires at around 120psi, so I inflate to 130 about 10 hours before I ride.

I ride to work (20 miles), then ride home 8 hours later. By the time I get home the pressure is down to about 100-110 psi.

I was curious what other rider's experience is with pressure loss, and what is considered normal pressure loss over time.

Not sure if it makes a difference, but I am currently using Continental tubes with Gastorskin tires and the tubes are 100% intact, verified by testing in a water tank.

Issaquatch

In 24 hours, it isn't uncommon for my butyl tubes to leak 10 psi and for my latex tubes to leak 20 psi.

Also, the rate of leakage is usually higher when the initial psi is higher. On butyl tubes, I might lose 10 psi the first day after they are pumped to 110psi and then only a few psi a day after that. On latex tubes, I might lose 20 psi the first day, and then an additional 10 psi every day after that (I've seen them drop down to 50psi after 5-6 days).

Pumping up your tires only takes a minute. I think it makes most sense to do it every day you ride, right before you leave on your ride in the morning.

surgeonstone

I pump every 2 or 3 days and go from 120 down to 90-100 in that time

StephenH

I air mine up every day, but I think 1/2 the loss is just when I put the pump on.

Homebrew01

It varies. I've had tubes that didn't seem to lose any over a week or more. Wish I had more of those.

10 Wheels

In 24 hours, it isn't uncommon for my butyl tubes to leak 10 psi.

Same for mine.

banerjek

Rate of leakage also seems to vary with how much you ride. I guess that's logical since the pressure is effectively boosted when you're riding. I pump my tires up for every ride but I notice that air tends to stay in tires longer when the bike hasn't been ridden.

collegeskier

When you attach your pump to your tire you lose air pressure through some loss of air, but even more the hose of the pump has to be inflated to 120 psi. I am not motivated enough to figure this out right now but at upper pressures with road tires the loss is probably more then the loss through the tube.

Nachoman

.5 psi loss every hour.

Gluteus

Same here.

Kenda tubes.

collegeskier

If my math and physics is right, attaching a 1 meter long 6mm wide (inner diameter) hose to your 700x23 tires with them pumped up to 120 psi, tire pressure and gage will drop about 4 psi. Double the width of the pump hose and you will end up with 10 psi loss.

seejohnbike

actually, it depends on how your pump operates: if as soon as you clamp on the adapter, you see your pump pressurize, then some of your pressure loss is coming from the pump.

if you clamp on the pump, and need to start pumping before the gauge springs to life, then you can't factor in losses via the pump. When you loosen the knurled nut at the end of the presta valve, it's the pressure within the tire that's holding the valve closed. only once you pump the hose up to equivalent (or more) psi will there be a pressure difference to facilitate the valve actually opening. ya dig?

otherwise, generally tubes will leak more than none, and less than some. I can usually get about a week out of my tubes before I feel the urge to top them off (120psi at beginning of week, maybe 90 psi by weeks end. sometimes even longer)

best advice: crank down on the little knurled thing on the presta valve. the tighter that seal is, the longer you can stave off premature tube deflation.

Eclectus

I use utility-grade (thicker) butyl tubes, and can ride 2 days, 4-6 hours, start at 110, lose 10ish pounds by the end of day 2. I'm a Clyde, no problems pinch-flatting. Thicker tubes don't extrude as easily as thinner tubes. If we had smooth roads here, I'd probably ride 120 and pump before every ride, but we have crappy surfaces, so a little softer ride is fine. Plus it is windy here, so I'm not riding that fast anyway for most of my rides.

thump55

I just threw my old training wheels back on this weekend, they'd been sitting all summer...they were at 80 PSI (from 110/105).

noisebeam

I'm surprised at these leak rates.

In summer months, 95F at night storage, 110-115F during the day a tire inflated to 120psi will be 110psi ~2days later. In the winter (40F night storage, 70F day) same tire and tube* will last a week before loosing 10psi.

*usually a conti race light as I got a deal on a dozen of them.