Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 11-30-11, 03:49 PM   #1
cineris
Newbie
Thread Starter
 
Join Date: Nov 2011
Bikes:
Posts: 1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Pinhole Leak in Tube

I found my bike today with a flat rear tire. I took the tube out of the tire and inspected it, and after putting it under water, I found a tiny pinhole where the leak was. It is on the rim side of the tube, about where the tube would contact the bead of the tire.

I've heard of people getting tiny wires separating from the tire and causing such problems, but I'm using a foldable tire, not a wire-bead, so I can't see that this would be the problem. I've ran a cloth around the inside of the tire and the rim multiple times, and haven't snagged anything on either, and I've run my fingers over both to make sure that there wasn't something really small there.

The only thing I found was that the rubber along the very edge of the bead is pretty rough in a couple of places. Has anyone ever heard of, or had experience with, that causing a leak, or is it more likely that I just picked up something from the trail that I brushed away when I was checking for it?
cineris is offline   Reply With Quote
Old 11-30-11, 04:05 PM   #2
dsbrantjr
Senior Member
 
dsbrantjr's Avatar
 
Join Date: Sep 2010
Location: Roswell, GA
Bikes: '93 Trek 750, '92 Schwinn Crisscross, '93 Mongoose Alta
Posts: 4,736
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 121 Post(s)
cineris: Try running a cotton ball around the suspect area. It also might help to turn the tire inside-out when checking for embedded objects.
dsbrantjr is offline   Reply With Quote
Old 11-30-11, 04:20 PM   #3
10 Wheels
Galveston County Texas
 
10 Wheels's Avatar
 
Join Date: Nov 2007
Location: In The Wind
Bikes: 2010 Expedition, 03 GTO
Posts: 30,096
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 386 Post(s)
Wire



Glass

__________________
[SIZE=1][B]What I like about Texas[/B]
http://www.youtube.com/watch?v=PGukLuXzH1E

Set F1re To The Ra1n ( NY Night Rain Ride)
http://www.youtube.com/watch?v=W7jfcWEkSrI
10 Wheels is online now   Reply With Quote
Old 11-30-11, 05:28 PM   #4
Looigi
Senior Member
 
Looigi's Avatar
 
Join Date: Dec 2010
Bikes:
Posts: 8,951
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
The tube may have been slightly twisted so that the part where you found the hole was aligned with the tread rather than the bead. In any case, the pix above show things like I've found in my tires, sometimes even smaller. In fact yesterday I got a slow leak during a ride, stopped, removed the tube, could not find the hole in it, carefully inspected the tire, found nothing, put a new tube in, and rode on only to get another slow leak. I made it home and was able to find the leak in the tube and then look at the corresponding place in the tire. I found I nearly microscopic flake a glass embedded in the tire. I had a similar experinece about 6 months ago caused by two very thin pieces of wire embedded in the tire about 180 degrees apart. I found the one corresponding to a leak and removed it only to get another slow leak a few days later caused by the second piece of wire.
Looigi is offline   Reply With Quote
Old 11-30-11, 11:10 PM   #5
Camilo
Senior Member
 
Join Date: Apr 2007
Bikes:
Posts: 4,263
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
I had a batch of tubes (I think I ordered two or three from the same place, same time) all have pinhole leaks. I could find no culprit, and no tubes before or after have ever had that problem.
Camilo is offline   Reply With Quote
Old 12-01-11, 01:04 PM   #6
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 22,040
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 1096 Post(s)
Quote:
I found a tiny pinhole where the leak was. It is on the rim side of the tube, about where the tube would contact the bead of the tire.
bead wire exposed?
Bad tube is always possible..

Last edited by fietsbob; 12-01-11 at 01:45 PM.
fietsbob is offline   Reply With Quote
Old 12-01-11, 02:21 PM   #7
AEO
Senior Member
 
AEO's Avatar
 
Join Date: Jun 2007
Location: A Coffin Called Earth. or Toronto, ON
Bikes: Bianchi, Miyata, Dahon, Rossin
Posts: 12,258
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by fietsbob View Post
bead wire exposed?
Bad tube is always possible..
I've had one of those. There's just nothing you can do to fix an exposed bead wire, except getting a new one.
__________________
Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
http://sanfrancisco.ibtimes.com/arti...ger-photos.htm
AEO is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 05:21 PM.