tube leak, but not when off of wheel?
03-03-13, 09:58 AM
#1
Senior Member
Thread Starter
tube leak, but not when off of wheel?
I installed a new tire a couple days ago. Tube was fine at the time, I rode 35 miles yesterday. After the ride, I noticed my tire was flat an hour or two post-ride. This morning, I removed the tire, and checked the tube for leaks, but no leak found. Does that mean there something wrong with the valve on the tube?
03-03-13, 10:02 AM
#2
Senior Member
Thread Starter
I did notice that I had to 'adjust' the valve when trying to inflate the tube. If I didn't, the tire pump wouldn't pump air into the tire, it would just 'queue up' in the pump's nozzle - or whatever it's called. But if I adjust the valve, and try to pump again, it would fill the tube up.
03-03-13, 10:03 AM
#3
Mechanic/Tourist
It means you did not find the leak and need to check it under water, as there is less pressure in the tube when off the tire.. You used the same tube so it is not logical to assume something wrong with the valve. Part of checking the tube for leaks is checking the valve stem.
03-03-13, 10:10 AM
#4
Senior Member
Thread Starter
It means you did not find the leak and need to check it under water, as there is less pressure in the tube when off the tire.. You used the same tube so it is not logical to assume something wrong with the valve. Part of checking the tube for leaks is checking the valve stem.
Thanks for the help!
03-03-13, 10:44 AM
#5
Mechanic/Tourist
Yep, you're right! There's a super tiny hole leaking a tiny amount of air. I've never seen something like that before! Thanks for the advice - to check it under water. I did think about doing that, but assumed no way, it couldn't be the tube since it held air. But, makes sense though that there is less pressure when the tube is off the tire.
Thanks for the help!
Thanks for the help!
03-04-13, 10:47 AM
#6
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I installed a new tire a couple days ago. Tube was fine at the time, I rode 35 miles yesterday. After the ride, I noticed my tire was flat an hour or two post-ride. This morning, I removed the tire, and checked the tube for leaks, but no leak found. Does that mean there something wrong with the valve on the tube?
Tire wire (as in "steel belted radials") can make tiny holes which take a few hours to let the air out. They can also embed inside bike tires where you can't find them just running your finger around the inside of the tire.
You need to put the tube under water and look for a very small slowly forming air bubble when you squeeze it, and then look at the tire's inside at the corresponding location under a bright light while you flex it.
