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.

Tire/tube problem

Old 08-31-12, 07:33 PM
  #1  
Mister Scott
Junior Member
Thread Starter
 
Mister Scott's Avatar
 
Join Date: Aug 2012
Location: Memphis
Posts: 9
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Tire/tube problem

So last night I went for a wet ride on my road bike in the remnants of Hurricane Isaac. Along the way, I hear a rhythmic "sss...sss...sss...sss" that sounded like it was coming from the rear tire. I also thought a felt air blowing onto my right leg. So I figured I had a pinch flat a pulled over. The tire felt like it had plenty of air though, so I rode another 4 miles or so. Today, I did not ride, but I noticed the that the rear tire was flat. I took the bike out to the garage and aired up the rear to about 120 psi. It seems to be holding air for the time being.

Any ideas on what the problem could be?
Mister Scott is offline  
Old 08-31-12, 07:36 PM
  #2  
10 Wheels
Galveston County Texas
 
10 Wheels's Avatar
 
Join Date: Nov 2007
Location: In The Wind
Posts: 30,995

Bikes: 2010 Expedition, 03 GTO

Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 709 Post(s)
Take the tube out, air it up and place sections of it in water and look for bubbles.
__________________
Fred "The Real Fred"
10 Wheels is offline  
Old 08-31-12, 07:49 PM
  #3  
himespau 
Senior Member
 
himespau's Avatar
 
Join Date: Jun 2008
Location: Louisville, KY
Posts: 10,897
Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Quoted: 1225 Post(s)
Originally Posted by 10 Wheels View Post
Take the tube out, air it up and place sections of it in water and look for bubbles.
+1, then either patch it or replace it. I'd patch it just so you have practice when you find you need to do it late one night in the middle of nowhere in the rain when all your spares have flats too. That is assuming you carry a patch kit with you in addition to spare tubes.
himespau is offline  
Old 08-31-12, 07:52 PM
  #4  
10 Wheels
Galveston County Texas
 
10 Wheels's Avatar
 
Join Date: Nov 2007
Location: In The Wind
Posts: 30,995

Bikes: 2010 Expedition, 03 GTO

Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 709 Post(s)
Originally Posted by 10 Wheels View Post
Take the tube out, air it up and place sections of it in water and look for bubbles.
If you find a tiny hole in the tube, try to match it to the tire and look for glass or a tiny wire.



__________________
Fred "The Real Fred"
10 Wheels is offline  
Old 08-31-12, 08:10 PM
  #5  
seedsbelize 
Refugee
 
Join Date: Nov 2010
Location: Tixkokob, Yucatán, México
Posts: 10,804
Mentioned: 86 Post(s)
Tagged: 1 Thread(s)
Quoted: 4474 Post(s)
There is something in the tire, yes, and it only leaks while rolling.
__________________
I just love riding a vintage road bike. The smooth speed and quick response of the steel has to be one of the most enjoyable experiences I know.

My bikes: 58cm '72 Schwinn World Voyageur, 24" '79 Trek 930, 58cm '84 Schwinn Letour Luxe, with couplers, 61cm '92 Schwinn Paramount (Panasonic) [Incoming: 60cm '88 Centurion Ironman Expert, 24" '80 Trek 414]
I will buy no more bikes forever.
seedsbelize is offline  
Old 08-31-12, 08:27 PM
  #6  
himespau 
Senior Member
 
himespau's Avatar
 
Join Date: Jun 2008
Location: Louisville, KY
Posts: 10,897
Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Quoted: 1225 Post(s)
If you don't see a cause with your eyes, run a cotton ball on the inside of the tube in the area you see bubbles (assuming you have a way of lining the tire up to the tube (I like to put the valve and the tire label in the same spot). That'll catch things you can't see, but don't want to snag your finger on.
himespau is offline  
Old 08-31-12, 08:54 PM
  #7  
curbtender
Senior Member
 
curbtender's Avatar
 
Join Date: Mar 2007
Location: SF Bay Area, East bay
Posts: 5,255

Bikes: Marinoni, Kestral 200 2002 Trek 5200, KHS Flite, Koga Miyata, Schwinn Spitfire 5, Schwinn Speedster, Mondia Special, Univega Alpina, Miyata team Ti, MB3

Mentioned: 23 Post(s)
Tagged: 0 Thread(s)
Quoted: 451 Post(s)
I've had leaks at the base of the stem that have done that.
curbtender is online now  
Old 08-31-12, 09:23 PM
  #8  
Mister Scott
Junior Member
Thread Starter
 
Mister Scott's Avatar
 
Join Date: Aug 2012
Location: Memphis
Posts: 9
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks for all the replies. I've never experienced a slow leak with a tube before (motorcycles and bicycles). They've either held or gone instantly flat. Evidently I do have a slow leak though. A pinch test a few minutes ago suggested the tire has lost some air over the last couple of hours or so. I'll probably take the lazy route and just replace the tube as opposed to patching it.

Flats are the bane of my riding efforts.
Mister Scott is offline  
Old 08-31-12, 09:59 PM
  #9  
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 36,049

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Mentioned: 121 Post(s)
Tagged: 1 Thread(s)
Quoted: 4331 Post(s)
Originally Posted by curbtender View Post
I've had leaks at the base of the stem that have done that.
leaks where the valve attaches are more common these days, especially with the new flangeless Presta valves many tube makers are using. I often get intermittent leaks with these valves. Wiggle the valve one way it leaks, wiggle it another and it'll be fine for a week, then leak anew.

For some reason I find that many of these will wold up fine for a long time, but after a hard ride in the rain will fail. I suspect that water is somehow attacking the glue that holds these together, and when I check defective tubes I find a decent amount of oxidation where the bond failed. I now punch a hole in a feathered patch and reinforce every tube before using it, or packing it as a spare. It seems to help, but I'm still very disappointed with the quality of tubes made in the last 10 years o so.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline  
Old 08-31-12, 10:02 PM
  #10  
Valleybikes
Newbie
 
Join Date: Aug 2012
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Mark where the valve is on the side of the tire with a pen and on the valve on the same side as the tire take the tube out air it up find the leak (if you have to put it in soapy water do so then line up the mark on the valve with the mark on the tire and find what made it leak
Valleybikes is offline  
Old 09-01-12, 08:44 AM
  #11  
curbtender
Senior Member
 
curbtender's Avatar
 
Join Date: Mar 2007
Location: SF Bay Area, East bay
Posts: 5,255

Bikes: Marinoni, Kestral 200 2002 Trek 5200, KHS Flite, Koga Miyata, Schwinn Spitfire 5, Schwinn Speedster, Mondia Special, Univega Alpina, Miyata team Ti, MB3

Mentioned: 23 Post(s)
Tagged: 0 Thread(s)
Quoted: 451 Post(s)
You'd think someone would have developed a product like the hole protectors for binder paper, Hmmm, wonder how they would work?
curbtender is online now  
Old 09-01-12, 08:53 AM
  #12  
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 36,049

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Mentioned: 121 Post(s)
Tagged: 1 Thread(s)
Quoted: 4331 Post(s)
Originally Posted by curbtender View Post
You'd think someone would have developed a product like the whole protectors for binder paper, Hmmm, wonder how they would work?
Tubes have always been reinforced at the valve hole, so that wouldn't be new. It's just the way that valves are being attached to molded tubes that crates the problem. The new design has a taller, narrower base with the tube joined to the side, vs. the old design where the valve has a flange inside the tube. The older design has the virtue that pressure compresses the joint, while the new version is entirely dependent on bonding.

The reason for the change was mainly because the larger flanges caused issues on narrow rims, and there was a cost savings (after the tube molds were modified) in production.

The makers are aware of the problems with the new design, and I assume working to correct them, but it'll be a while before all the old stock flushes through the distribution system. My personal problem is that I have a decent stock left over from the early (bad) years of this design.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline  
Old 09-03-12, 06:34 AM
  #13  
Mister Scott
Junior Member
Thread Starter
 
Mister Scott's Avatar
 
Join Date: Aug 2012
Location: Memphis
Posts: 9
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
So I took the tube off and it was still holding a little bit of air. I inflated it and it immediately lost most but not all of the air. I put it in the sink and found the leak - a tiny pinhole size puncture (I also happened to notice the corresponding hole in the tire later while replacing the tube).

I had a new tube that had been on hand for years. I installed it and aired it up to about 120 psi. As I went to put the tire on the bike - POW!!!! Scared the crap out of me as well as my nosey Siamese kitten who was "helping me". I removed the *new* tube and discovered that it had blown out within the section where the valve is attached to the tube.

I then took a trip to the new LBS nearby. They confirmed it probably was not user error that caused the failure and sold me a couple of new tubes. I rode a meager 6 wet miles yesterday and all was well.
Mister Scott is offline  
Old 09-03-12, 06:53 AM
  #14  
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Posts: 29,162

Bikes: Catrike 559 I own some others but they don't get ridden very much.

Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 1107 Post(s)
You'll get more punctures on a wet ride. Some say it's because the glass shards stick to the tires more, some cay it's because the water lubricated the shards so they can penetrate the tire more easily. Either way, that's what happened. If the leak is that slow it may be hard to find but, until you find it and fix it, you are doomed.
Retro Grouch is offline  
Old 09-03-12, 07:06 AM
  #15  
Mister Scott
Junior Member
Thread Starter
 
Mister Scott's Avatar
 
Join Date: Aug 2012
Location: Memphis
Posts: 9
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Originally Posted by Retro Grouch View Post
You'll get more punctures on a wet ride.
That's interesting.
Mister Scott is offline  

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


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.