Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Weird flat, can't figure out the cause

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.

Weird flat, can't figure out the cause

Old 04-06-17, 06:12 PM
  #1  
DinnerSocks
Newbie
Thread Starter
 
Join Date: Apr 2017
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Weird flat, can't figure out the cause

I've just gotten brand new Soma everlong 700x26 tires for my Allez because the old ones had enough holes that my tubes started blowing. I also replaced the back tube with a new 700x(18-25) tube but the guy at the store said the 1mm difference in width wouldn't matter. My front tire is inflated and perfectly fine but my back tire refuses to inflate. When I go to pump it up it seems to take on and hold a few psi but then the air just starts to leak out (I think from the connection between the presta valve and the pump) I tried a different pump but I had the same issue.
DinnerSocks is offline  
Old 04-06-17, 06:18 PM
  #2  
tyrion
Senior Member
 
tyrion's Avatar
 
Join Date: Oct 2015
Location: San Diego, California
Posts: 2,297

Bikes: Breezer Radar

Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 1202 Post(s)
Liked 70 Times in 47 Posts
You should get a bucket of water, submerge the tube in it and pump it up and see where the bubbles come from.
tyrion is offline  
Old 04-06-17, 06:31 PM
  #3  
DinnerSocks
Newbie
Thread Starter
 
Join Date: Apr 2017
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Just gave that a shot, it definitely looks like the air is coming from the pump/head of the valve area
DinnerSocks is offline  
Old 04-06-17, 06:41 PM
  #4  
curbtender
Senior Member
 
curbtender's Avatar
 
Join Date: Mar 2007
Location: SF Bay Area, East bay
Posts: 5,424

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: 25 Post(s)
Tagged: 0 Thread(s)
Quoted: 499 Post(s)
Liked 12 Times in 11 Posts
Try tightening the valve down and then reopen and inflate again. Sometimes that seal needs to set itself in.
curbtender is offline  
Old 04-06-17, 06:51 PM
  #5  
DinnerSocks
Newbie
Thread Starter
 
Join Date: Apr 2017
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
I did a great deal of tightening and checking, at least on every part I could think to. One person on the internet suggested that the core of the presta valve might be loose and I even tried tightening that to no avail.
DinnerSocks is offline  
Old 04-06-17, 06:54 PM
  #6  
strat
Newbie
 
Join Date: May 2014
Location: louisiana
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
try putting a schrader adapter on it and pump it up with another pump or gas station
strat is offline  
Old 04-06-17, 06:59 PM
  #7  
DinnerSocks
Newbie
Thread Starter
 
Join Date: Apr 2017
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Haven't got one at home but I know where I can find one, I'll give it a shot probably sometime tomorrow. Thanks for the suggestion!
DinnerSocks is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
solbrothers
Classic & Vintage
12
11-22-11 08:18 PM
EddyR
Classic & Vintage
2
07-27-11 08:17 PM
ModoVincere
Foo
25
12-08-08 11:41 AM
2packaday?
General Cycling Discussion
3
10-15-07 09:02 AM
Bobo the Feared
Southern California
14
06-04-07 08:24 PM

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.