Go Back  Bike Forums > Bike Forums > General Cycling Discussion
Reload this Page >

slight tear at Schrader valve base

Notices
General Cycling Discussion Have a cycling related question or comment that doesn't fit in one of the other specialty forums? Drop on in and post in here! When possible, please select the forum above that most fits your post!

slight tear at Schrader valve base

Old 07-24-21, 01:03 PM
  #1  
colt1954
Junior Member
Thread Starter
 
Join Date: Apr 2021
Posts: 17
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 1 Time in 1 Post
slight tear at Schrader valve base

Hi,
I have a slight tube tear on the base of the my valve, this is the second time this has happened, now on a new tube, any ideas why it's failing there?

Any manouveres that could cause it?

Colin
colt1954 is offline  
Old 07-24-21, 01:18 PM
  #2  
CliffordK
Senior Member
 
CliffordK's Avatar
 
Join Date: Nov 2014
Location: Eugene, Oregon, USA
Posts: 26,044
Mentioned: 209 Post(s)
Tagged: 0 Thread(s)
Quoted: 14395 Post(s)
Liked 2,402 Times in 1,790 Posts
You need to make sure that the valve is 100% perpendicular to the rim. If the valve is not straight, it will eventually tear and leak.

It may be possible to slightly round the corners of the valve hole with some fine sandpaper or a chainsaw file (or both).
CliffordK is offline  
Likes For CliffordK:
Old 07-24-21, 01:21 PM
  #3  
Iride01
Hits [ENTER] b4 thinking
 
Iride01's Avatar
 
Join Date: Jul 2017
Location: Mississippi
Posts: 8,217

Bikes: '20 Tarmac Disc Comp '91, '78 Raleigh Competition GS

Mentioned: 34 Post(s)
Tagged: 0 Thread(s)
Quoted: 3236 Post(s)
Liked 1,830 Times in 1,299 Posts
I was getting failures on my presta valves at the base. The culprit was the air chuck that wasn't fully releasing and simply pulling on the valve stem too much as I removed the chuck. Maybe this can happen with Schrader's too if the chuck pulls a lot. But Schrader valves have a beefier boot around their base typically.

With Schrader valves, typically an issue I see is that people ride them with too little air and the tube walks (moves) inside the tire and then the stem gets pulled to an angle and slightly into the rim. So every turn of the wheel with the valve stem at an angle is working to rip that valve from the tube.

There are other things too like roughness around the hole in the rim or the hole way too big if someone did a DIY presta to schrader conversion.
Iride01 is offline  
Old 07-25-21, 04:11 AM
  #4  
colt1954
Junior Member
Thread Starter
 
Join Date: Apr 2021
Posts: 17
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Well not sure why it would not be straight, and really it is what it is...but making the hole less abrasive is a good point!
colt1954 is offline  
Old 07-25-21, 04:13 AM
  #5  
colt1954
Junior Member
Thread Starter
 
Join Date: Apr 2021
Posts: 17
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by Iride01 View Post
I was getting failures on my presta valves at the base. The culprit was the air chuck that wasn't fully releasing and simply pulling on the valve stem too much as I removed the chuck. Maybe this can happen with Schrader's too if the chuck pulls a lot. But Schrader valves have a beefier boot around their base typically.

With Schrader valves, typically an issue I see is that people ride them with too little air and the tube walks (moves) inside the tire and then the stem gets pulled to an angle and slightly into the rim. So every turn of the wheel with the valve stem at an angle is working to rip that valve from the tube.

There are other things too like roughness around the hole in the rim or the hole way too big if someone did a DIY presta to schrader conversion.
Good reply yes I could imagine the valve moving a fraction due to lost pressure...

Not sure what you mean by the 'chuck'
colt1954 is offline  
Old 07-25-21, 04:15 AM
  #6  
colt1954
Junior Member
Thread Starter
 
Join Date: Apr 2021
Posts: 17
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by CliffordK View Post
You need to make sure that the valve is 100% perpendicular to the rim. If the valve is not straight, it will eventually tear and leak.

It may be possible to slightly round the corners of the valve hole with some fine sandpaper or a chainsaw file (or both).
Well not sure why it would not be straight, and really it is what it is...but making the hole less abrasive is a good point!
colt1954 is offline  
Old 07-25-21, 04:32 AM
  #7  
CliffordK
Senior Member
 
CliffordK's Avatar
 
Join Date: Nov 2014
Location: Eugene, Oregon, USA
Posts: 26,044
Mentioned: 209 Post(s)
Tagged: 0 Thread(s)
Quoted: 14395 Post(s)
Liked 2,402 Times in 1,790 Posts
Originally Posted by colt1954 View Post
Well not sure why it would not be straight, and really it is what it is...but making the hole less abrasive is a good point!
Obviously I haven't seen your bike, but it is not uncommon to see crooked valves. These are just a couple of images taken off of the internet.





It can happen for a number of reasons. Either during installation of the tube, or riding with too low of pressure.

I tend to deflate my tube, and drag the fingers along the outside of the tire, going around the rim to straighten the valve (DON'T DRAG FINGERS AROUND CONTINENTAL GATORSKIN AND SIMILAR TIRES).

Some wheels seem to be fine with crooked valves, others are not which may mean it is a problem with sharp corners and burs, often exacerbated by crooked valves.

Last edited by CliffordK; 07-25-21 at 04:40 AM.
CliffordK is offline  
Likes For CliffordK:
Old 07-25-21, 06:07 AM
  #8  
rumrunn6
Senior Member
 
rumrunn6's Avatar
 
Join Date: Jul 2008
Location: 25 miles northwest of Boston
Posts: 25,330

Bikes: Bottecchia Sprint, GT Timberline 29r

Mentioned: 105 Post(s)
Tagged: 0 Thread(s)
Quoted: 3874 Post(s)
Liked 1,059 Times in 740 Posts
Originally Posted by colt1954 View Post
...but making the hole less abrasive is a good point!
I drill all my wheels to fit Schrader valves. can't stand presta. after drilling I debar them w/ a cpl diff. small files until they feel good to my touch, then coat the hole w/ some black paint. not sure why a wheel with an original Schrader hole would need treatment, but yeah feel it & see if it feels sharp. suppose it could be a manufacturing defect. sounds like it has been the same wheel, twice? just 2 times? how old is the bike/wheels? what brand are the wheels? wonder what brand tubes you are using, as well. & are you pumping there tires to a high enough pressure?



rumrunn6 is offline  
Old 07-25-21, 08:15 AM
  #9  
cyccommute 
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Posts: 24,273

Bikes: Some silver ones, a red one, an orange one and a few titanium ones

Mentioned: 124 Post(s)
Tagged: 1 Thread(s)
Quoted: 4272 Post(s)
Liked 1,784 Times in 1,085 Posts
Originally Posted by colt1954 View Post
Hi,
I have a slight tube tear on the base of the my valve, this is the second time this has happened, now on a new tube, any ideas why it's failing there?

Any manouveres that could cause it?

Colin
What are you using to pump up the tires? If the valve is failing when using a floor pump, you may need to deburr the rim. Use a counter sink tool to chamfer the hole. Hereís a good hand one that will do the trick.

If, on the other hand, itís happening when you are using a frame pump, it may be the pump. A hand pump that you hold and pump perpendicularly to the wheel put a lot of stress on the valve. A pump with a hose like the Topeak Morph series will put less stress on the valve (and is easier to use).
__________________
Stuart Black
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
cyccommute is offline  
Old 07-25-21, 08:56 AM
  #10  
Iride01
Hits [ENTER] b4 thinking
 
Iride01's Avatar
 
Join Date: Jul 2017
Location: Mississippi
Posts: 8,217

Bikes: '20 Tarmac Disc Comp '91, '78 Raleigh Competition GS

Mentioned: 34 Post(s)
Tagged: 0 Thread(s)
Quoted: 3236 Post(s)
Liked 1,830 Times in 1,299 Posts
Originally Posted by colt1954 View Post
Not sure what you mean by the 'chuck'
The part on the end of the pump's hose that you attach to the valve stem to fill it with air.

Many on floor pumps have a clamp lever on the air chuck to hold them onto the valve. If the clamp lever doesn't release fully or something else happens to the air chuck might be harder to pull off and might easily be enough to strain the boot on many a presta valve tube. Perhaps Schrader valves too.

Do you fill your tires with air from a compressor or something that just has an air chuck that you hold on the Schrader valve? Perhaps you push the valve stem down in the rim as you fill with air and the boot is getting damaged from that. Especially if you are bottoming out the stem on the tire. If you are pushing the stem in as you fill the tire, don't. I just used my free hand to lay a finger on the stem and rim so as to wedge the valve so it didn't get pushed in.
Iride01 is offline  
Old 07-25-21, 10:02 AM
  #11  
colt1954
Junior Member
Thread Starter
 
Join Date: Apr 2021
Posts: 17
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by rumrunn6 View Post
I drill all my wheels to fit Schrader valves. can't stand presta. after drilling I debar them w/ a cpl diff. small files until they feel good to my touch, then coat the hole w/ some black paint. not sure why a wheel with an original Schrader hole would need treatment, but yeah feel it & see if it feels sharp. suppose it could be a manufacturing defect. sounds like it has been the same wheel, twice? just 2 times? how old is the bike/wheels? what brand are the wheels? wonder what brand tubes you are using, as well. & are you pumping there tires to a high enough pressure?



The hole in the wheel feels okish, but might try to lightly file edges or deburr if possible, don't have a tool, might use a bigger drill?
The wheel is less than a year old as is the bike, a Carbo X folding bike designed in the US.
Cannot see make on wheel, but the inner tube was 2-3 months old (second one) it had Taiwan marked on it....not sure if too low pressure has helped cause the problem.
colt1954 is offline  
Old 07-25-21, 10:05 AM
  #12  
colt1954
Junior Member
Thread Starter
 
Join Date: Apr 2021
Posts: 17
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by Iride01 View Post
The part on the end of the pump's hose that you attach to the valve stem to fill it with air.

Many on floor pumps have a clamp lever on the air chuck to hold them onto the valve. If the clamp lever doesn't release fully or something else happens to the air chuck might be harder to pull off and might easily be enough to strain the boot on many a presta valve tube. Perhaps Schrader valves too.

Do you fill your tires with air from a compressor or something that just has an air chuck that you hold on the Schrader valve? Perhaps you push the valve stem down in the rim as you fill with air and the boot is getting damaged from that. Especially if you are bottoming out the stem on the tire. If you are pushing the stem in as you fill the tire, don't. I just used my free hand to lay a finger on the stem and rim so as to wedge the valve so it didn't get pushed in.
Well, the puncture came whilst I was cycling - not sure it's done with when I pump up the tyre, unless you are suggesting I may have helped
start the damage off during pumping? But I have had weeks of puncture cycling!
colt1954 is offline  
Old 07-25-21, 10:07 AM
  #13  
colt1954
Junior Member
Thread Starter
 
Join Date: Apr 2021
Posts: 17
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by cyccommute View Post
What are you using to pump up the tires? If the valve is failing when using a floor pump, you may need to deburr the rim. Use a counter sink tool to chamfer the hole. Hereís a good hand one that will do the trick.

If, on the other hand, itís happening when you are using a frame pump, it may be the pump. A hand pump that you hold and pump perpendicularly to the wheel put a lot of stress on the valve. A pump with a hose like the Topeak Morph series will put less stress on the valve (and is easier to use).
Please see my comment re. not the pumping at fault on my other reply?
colt1954 is offline  
Old 07-25-21, 10:11 AM
  #14  
colt1954
Junior Member
Thread Starter
 
Join Date: Apr 2021
Posts: 17
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by CliffordK View Post
Obviously I haven't seen your bike, but it is not uncommon to see crooked valves. These are just a couple of images taken off of the internet.





It can happen for a number of reasons. Either during installation of the tube, or riding with too low of pressure.

I tend to deflate my tube, and drag the fingers along the outside of the tire, going around the rim to straighten the valve (DON'T DRAG FINGERS AROUND CONTINENTAL GATORSKIN AND SIMILAR TIRES).

Some wheels seem to be fine with crooked valves, others are not which may mean it is a problem with sharp corners and burs, often exacerbated by crooked valves.
My valve has never looked that crooked from my recollection, but maybe it gets worse with loss of tyre pressure (ie the tube slips around as suggested), I need to be more vigilant on tyre pressure and pay more attention to valve angle!
I will look at deburring also.
colt1954 is offline  
Old 07-25-21, 10:55 AM
  #15  
cyccommute 
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Posts: 24,273

Bikes: Some silver ones, a red one, an orange one and a few titanium ones

Mentioned: 124 Post(s)
Tagged: 1 Thread(s)
Quoted: 4272 Post(s)
Liked 1,784 Times in 1,085 Posts
Originally Posted by colt1954 View Post
Please see my comment re. not the pumping at fault on my other reply?
Stressing the valve seat doesnít necessarily result in an instant flat but it can start the process. Tubes and tires can creep while riding, especially if the tire is going flat slowly. If you have stressed the valve seat while pumping up the tire, it can tear the valve stem later while riding.
__________________
Stuart Black
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
cyccommute is offline  
Likes For cyccommute:
Old 07-28-21, 12:51 PM
  #16  
rumrunn6
Senior Member
 
rumrunn6's Avatar
 
Join Date: Jul 2008
Location: 25 miles northwest of Boston
Posts: 25,330

Bikes: Bottecchia Sprint, GT Timberline 29r

Mentioned: 105 Post(s)
Tagged: 0 Thread(s)
Quoted: 3874 Post(s)
Liked 1,059 Times in 740 Posts
Originally Posted by colt1954 View Post
The hole in the wheel feels okish, but might try to lightly file edges or deburr if possible, don't have a tool, might use a bigger drill?
no, I would not make the hole bigger. you probably don't need to file anything. the problem is probably something else, anyway
rumrunn6 is offline  
Old 07-29-21, 06:14 AM
  #17  
colt1954
Junior Member
Thread Starter
 
Join Date: Apr 2021
Posts: 17
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 10 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by rumrunn6 View Post
no, I would not make the hole bigger. you probably don't need to file anything. the problem is probably something else, anyway
Oh rest assured I was not suggesting to make the hole bigger! I was suggesting a much bigger drill to simply deburr the exisiting hole...
colt1954 is offline  
Likes For colt1954:

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 - Do Not Sell My Personal Information -

Copyright © 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.