Leaking tire
 

I just patched a hole on my inner tube (needle size) and stopped a leak, tested it under water and no bubbles but when I put it back in the tire and on the rim it loses air after a few minutes. What am I doing wrong? I feel like an imbecile. Just took the inner tube back out and it holds air, put in on the wheel/tire and it leaks again.:notamused:

Brandy

check the tire for anything that might press on the tube , a small piece of glass or stone ,anything . try using soapy water to see any bubbles show up .

Check the entire tube for leaks. Pump the tube up a lot to do that. Also check the valve to be sure the leak isn't there. Make sure there is nothing left in the tire to puncture the tube before you pump up the tire.

Cheers

Some leaks are hard to find. Inflate it as much as it can take (I've popped tires.) and put it in clean soapy water. I keep extra tubes in my box of bike stuff so I can discard an uncooperative tube without too much inconvenience (or swearing).

Dont forget to check the valve stem for leakage too.

-SP

Check the valve itself as well. The valve spring can weaken, break, or get gummed up and not close completely.

I start at the valve, and work my way around until the entire tube has been underwater, bit-by-bit.
Put a decent amount of air in the tube when checking, otherwise it might not leak out.

Submerge it in clean water. Or lather it up with soapy water. Either this or that.

Putting it in "clean soapy water" is redundant. (Not even mentioning that soapy water is not exactly clean.)

sometimes it's better to use a new tube. I don't get many punctures but when my children get the odd puncture, I just install a new tube

Obviously the tube still has a hole in it. Pump the tube up outside of the tire and let it sit overnight. It'll be flat in the morning. If you can't find the hole, replace the tube. Make sure nothing is poking it from inside of the tire or rim.

Also make sure you wiggle the valve stem around while holding the inflated tube underwater. Sometimes the base of the stem has a cut that only reveals itself when the stem is pushed to one side.