Bicycle Mechanics - How long do your tires hold air?

This is an annoying problem. We all know that if you leave your tires full of air for 3 months they lose air. And after a week they should get pumped up. But the rate of air-loss has been increasing, down to nearly-flat per four days. But they seem fine for a normal ride.

Does everybody go through this? It's both wheels -- and I'm not sure if I'm at a higher risk for flatting during a ride or if there's something with the wheels or the way I've replaced the tubes (but the tubes are a couple of low-mileage months old, and this is a very recent phenomenon.)

Anybody else deal with this? If so, what's your air-loss replacement threshold?

you either have leaking valves or some tiny holes. Assuming the latter, dig all the glass out of your tires with something sharp and replace your tubes or use a tank of water and a lot of patience and find the holes and patch them. Repeat step 1 frequently and step 2 will not be needed nearly so often.

No, the one week is about right for my road bikes. My MTBs can go for two or three weeks.

Not really. My tires still hold at least half of their air after 3 weeks. Going flat in 4 days doesn't sound too normal to me.

It depends on what the normal pressure is for the tires. Higher pressure tires and tubes leak air at a much faster rate than low pressure tires. Road bike tires normally carrying 100 to 120 psi should be pumped up before each ride. It would be normal to loose 10 to 20 psi overnight.

Al

Also depends upon the type of tube. Lightweight tubes leak air pretty darn fast. Pumped up to 120psi, they'll drop down to 70-80psi within a couple days. They also puncture easily with tiny thorns or glass-fragments, and tiny punctures can leak all the air out in 2-3 days.

Try using some Slime in those tubes, if they end up holding air longer, then you had a tiny hole somewhere.

i too find that i lose around 10-15 psi overnight, i pump every morning before my 35 miles of daily commuting. 700x32s at 100psi.

My MTB can go for about 2-3 weeks without noticeably losing air.

I too lose about 15 psi by the next day from about 120 to 105 on my 700x23 tires, more with the lightweight tubes, as mentioned.

I've come to recognize those tiny leaks or too worn tubes from gauging them and pumping up every morning. Seeing the lower than normal pressure is indicative.

Also depends upon the type of tube. Lightweight tubes leak air pretty darn fast. Pumped up to 120psi, they'll drop down to 70-80psi within a couple days. They also puncture easily with tiny thorns or glass-fragments, and tiny punctures can leak all the air out in 2-3 days.

Try using some Slime in those tubes, if they end up holding air longer, then you had a tiny hole somewhere.

Sorry but I really don't agree with this. I've had better luck with ultralite tubes than the heavier types. I think this is probably just due to better quality control. Slime does not work in high pressure road tubes and does nothing but add weight in the worst possible location on the bike.

Al

Sorry but I really don't agree with this. I've had better luck with ultralite tubes than the heavier types. I think this is probably just due to better quality control. Slime does not work in high pressure road tubes and does nothing but add weight in the worst possible location on the bike.

Al

My experience with ulta light (mainly Torelli) tubes and punctures would lead me to agree with you. However, I absolutely, consistently, do lose more pressure with them.

Look for very tiny holes. One source I've found increasingly in the department's bikes is tiny bits of steel-belt material. These can be only a few fractions of an inch long, and make holes that are very hard to isolate.
I have resorted to blowing the tube up quite hard and submerging in water, just as we used to do at the service stations when car tires still ran tubes.

I used to lose 10 to 15 lbs of pressure (from 120 psi) overnight. I switched to Michelin Airstop tubes and now lose less than 4 lbs overnight. This is important on 3 to 4 day tours where a tire pump is not always readily available. Continental Ultra Gatorskin tire with Michelin Airstop is a GREAT combination.

Thanks, all! I think it is the outer tire making wee holes in my tubes -- probably from the steel-belt stuff. These tires were getting pretty old anyway..time to head to the store!

This is an annoying problem. We all know that if you leave your tires full of air for 3 months they lose air. And after a week they should get pumped up. But the rate of air-loss has been increasing, down to nearly-flat per four days. But they seem fine for a normal ride.

Does everybody go through this? It's both wheels -- and I'm not sure if I'm at a higher risk for flatting during a ride or if there's something with the wheels or the way I've replaced the tubes (but the tubes are a couple of low-mileage months old, and this is a very recent phenomenon.)

Anybody else deal with this? If so, what's your air-loss replacement threshold?

Are the tubes latex?

If so, this is normal air loss, epecially if you are run ning high presssue tires.

Thanks, all! I think it is the outer tire making wee holes in my tubes -- probably from the steel-belt stuff. These tires were getting pretty old anyway..time to head to the store!

Steel belts?? What kind of tires are they?

I loose hardly any air from my tires, I will give them a little pump up ever month or so, but I could go about 4 months before I notice any air loss at all, I could safely go 6 months without pumping them up. I have 2.35" MTB tires... I am told to have it at 130 - 150 PSI

You're not saying that you pump your MTB tires to 130~150psi, right?

You're not saying that you pump your MTB tires to 130~150psi, right?
Can you spell S-N-A-K-E B-I-T-E?

You're not saying that you pump your MTB tires to 130~150psi, right?
I bought new Specialized 2.1 MTB tires that were rated for 80PSI max. I thought, great, I'll reduce that rolling resistance and pumped those suckers up to about 75PSI. Then I took them out on a very technical, VERY rooty trail. The result is too ugly and painful to describe. Suffice it to say I took flying lessons......................over the bars. I'll never do that again, at least not on that type of trail.

I go 1000 to 3000 miles during the summer with brand new tires before needing air. If they go flat in 2-3 days and have no repairable leaks the tubes are toast. Tires go when I see sidewall cords, need to boot a cut, see a second layer of threads in the belly, or get 4 or 5 flats in a week; whichever comes first. My last tires went 7000 miles.

Wow, my MTB tyres hardly loose pressure at all/ leak air at all! I mean after maybe a month, if the bike has just been sitting around they would go slightly flat but besides that it has never been a problem. Dont get me started on how quick tubeless tyres loose air though!