Is it common to lose air from tyres?

[mobi]

Hi

I'm not riding my bike frequently due to change in job. Only ride Sat/Sun. But I noticed that my tyres are losing significant pressures in 2 weeks. If I pump 50 PSI today, next weeks it goes down to 30 PSI and next to next week it is like 5-10 PSI.

Is there any DIY check I can do before taking it to a tyre shop?

Thanx

 

[Steve H]

I generally need to pump my tyres every few weeks to keep them topped up, but they don't lose as much pressure as you are describing here. Is it both tyres that lose the pressure or mainly one of them. If it was just one, then it could be a slow puncture, but if it is happening to both in the same way this would be unusual. I put about 65psi in my mtb tyres and they will lose around 10 psi every couple of weeks.

 

[Hacienda71]

I find my road bike will lose some pressure after two or three rides but only 10 or 20 psi out of 110 psi. The amount you are losing seems a little excessive. You might have a slow puncture or a dodgy valve. If it is both tyres seems a bit strange. What type of riding are you doing? Off road or road or smooth tracks? May be worth changing your innertubes.

 

[cyberknight]

I find my road bike will lose some pressure after two or three rides but only 10 or 20 psi out of 110 psi. The amount you are losing seems a little excessive. You might have a slow puncture or a dodgy valve. If it is both tyres seems a bit strange. What type of riding are you doing? Off road or road or smooth tracks? May be worth changing your innertubes.

I was going to say the same , over a week i lose maybe the same on 110 psi .

I would also check the tyres and rims to see if there is anything that could be causing the leak.
How old are the inner tubes? i find that if they are really old they can degrade,certainly bikes i have picked up on freecycle have inner tubes like holey cheese.

 

[NormanD]

Place some soapy water over the schrader / presta valve and check for bubbles, also where the valve enters the rim is a good place to start.  I've found with the presta valve type, that it will lose lots of air if the valve screw is not secure.

Oh and another point too, check with the dust cap fitting and inside the dust cap itself, my son had a problem with his front tyre kept going flat, so after three inner tube replacements and a tyre change it turned out it was the dust cap itself causing the problem, it had a little nib on the inside of it, so when it was screwed onto the valve, it was just enough to depress the valve and cause a slow leak.

Lesson learnt on that one    

 

[Fab Foodie]

It depends on tubes and pressures. High pressure latex tubes need pumpping every day, heavier rugular tubes slightly less so, but on my road-bike I'll have to pump them back up to 120 psi every other day. As they're both doing the same thing, maybe it's just the quality of the tube and valves.

 

[mobi]

Thanks for the replies chaps. I think valve may be a problem. I bought the bike 3 years back as a used one. So I guess it is couple of years old.

I'll try to sort out the tyres - otherwise it may be cheaper to buy a new bike altogether

 

[MacB]

Now that would be funny, bought a new bike coz the inner tubes weren't good, not sure my wife would take that one!

 

[ianrauk]

Now that would be funny, bought a new bike coz the inner tubes weren't good, not sure my wife would take that one!

I have my suspicions about Topcat1 and the above statement.

 

[fossyant]

My Latex tubed best bike has rather squidgy tyres now - pumped up to 110-120 PSI a week ago, less than 20 I'd say now (PS haven't ridden it for a week)

 

[Bman]

Wow.. I usually put 40-50psi in my MTB tyres. Yes, they lose pressure over time, but I would say its as little as 5psi every 3 months!

 

[StuartG]

I have used continental tubes for many years and have had no problem with air loss. Needing an extra 20mb every month to keep up to 70/80 on 700x32.

Got a new bike with 23 tyres. Needs 20/30 every week to keep it up to 80/90. Both tyres equally so its not a dodgy valve. Have yet to take tyres off so make is unknown.

 

[jimboalee]

To test for slow puncture.

Get the tube out and inflate it to twice its normal size and immerse in a bathful of water.

Usually with Presta, its the bond between rubber and metal valve stem. If this is the case, its a scrappun.
Some tubes have a weak seam around the inside ( where it sits on the rim tape ). If this is the case, its also a scrappun.

 

[gb155]

On my Roadie I found i'd lose approx 35psi per week, however since I have got a decent set of rims that figure is now more like 5 psi a week. (Starting point is 110psi)

 

[decca234uk]

Perfectly normal, rubber allows air out over time. I use my bike for commutting and training and usually have to get the pump out once a week.