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

Presto Valve question

Notices
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.

Presto Valve question

Old 09-20-14, 07:34 PM
  #1  
Newbie
Thread Starter
 
Join Date: Sep 2014
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Presto Valve question

After pumping the tire and removing the pump I found my valve no longer visible, I guess it is jammed inside. How soon should I change it and anticipate that I will get an air leak from that? Is it safe to ride?

Thank you for the advice.


Olga
olgaamu is offline  
Old 09-20-14, 07:49 PM
  #2  
That Huffy Guy
 
Johnny Mullet's Avatar
 
Join Date: Jun 2014
Location: Ashtabula, Ohio
Posts: 1,438

Bikes: Old School Huffy Bikes

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 79 Post(s)
Likes: 0
Liked 6 Times in 6 Posts
Not safe to ride like that. Deflate and start over. Won't deflate because the valve is inside? Buy a new tube and pirce the old one with an ice pick through the hole in the rim. An $8.00 tube now will save from from a long walk home.
Johnny Mullet is offline  
Old 09-20-14, 08:50 PM
  #3  
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,918

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: 140 Post(s)
Tagged: 1 Thread(s)
Quoted: 5893 Post(s)
Liked 2,755 Times in 1,538 Posts
Broken PV valve stems are about as common as 3 leaf clovers. (maybe not quite that common). It really doesn't natter because a PV is a simple check valve and the tire pressure alone is enough to keep it reliably closed. The only issue is that the OP will now need a pin of some kind to let air out if he wants to.

BTW- the little nut and stem extension aren't somehow jammed inside the valve. They're inside the pump head, or fell out after you removed the pump and dropped on the floor.

Yes, as long as the tire holds air, which it will 99% of the time, the tire is safe. The worst that can happen is that the tire loses air and goes flat, and flats, regrdless of cause are inconvenient, but not dangerous.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

Just because I'm tired of arguing, doesn't mean you're right.

“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.

Last edited by FBinNY; 09-20-14 at 09:13 PM.
FBinNY is offline  
Old 09-20-14, 08:57 PM
  #4  
Senior Member
 
Join Date: Sep 2003
Location: Allen, TX
Posts: 1,916

Bikes: Look 585

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 25 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by olgaamu
After pumping the tire and removing the pump I found my valve no longer visible, I guess it is jammed inside. How soon should I change it and anticipate that I will get an air leak from that? Is it safe to ride?

Thank you for the advice.


Olga
It's not safe to ride, and it "Presta" . . .
bikepro is offline  
Old 09-20-14, 09:18 PM
  #5  
That Huffy Guy
 
Johnny Mullet's Avatar
 
Join Date: Jun 2014
Location: Ashtabula, Ohio
Posts: 1,438

Bikes: Old School Huffy Bikes

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 79 Post(s)
Likes: 0
Liked 6 Times in 6 Posts
Rim holes can be drilled to the correct size to fit standard schrader valve stem tubes.
Johnny Mullet is offline  
Old 09-20-14, 10:28 PM
  #6  
Senior Member
 
rebel1916's Avatar
 
Join Date: Aug 2011
Posts: 3,141
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 68 Post(s)
Liked 84 Times in 45 Posts
Originally Posted by Johnny Mullet
Rim holes can be drilled to the correct size to fit standard schrader valve stem tubes.
Just because you can, doesn't mean you should. And FB actually knows stuff. So the OP might should take his advice on this one.
rebel1916 is offline  
Old 09-20-14, 10:44 PM
  #7  
It's MY mountain
 
DiabloScott's Avatar
 
Join Date: Sep 2006
Location: Mt.Diablo
Posts: 10,005

Bikes: Klein, Merckx, Trek

Mentioned: 70 Post(s)
Tagged: 0 Thread(s)
Quoted: 4355 Post(s)
Liked 3,018 Times in 1,637 Posts
Even if it holds pressure just fine, you won't be able to add any more air for your next ride. As soon as you blow in some air the check valve will come off inside the tube.

And presta tubes ARE the standard.
DiabloScott is offline  
Old 09-21-14, 12:01 AM
  #8  
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,918

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: 140 Post(s)
Tagged: 1 Thread(s)
Quoted: 5893 Post(s)
Liked 2,755 Times in 1,538 Posts
Originally Posted by DiabloScott
Even if it holds pressure just fine, you won't be able to add any more air for your next ride. As soon as you blow in some air the check valve will come off inside the tube....
It's kind of funny, folks have been breaking the nut off and pumping their tubulars using Silca pumps daily and I don't know anyone who ever blew the stem into the tube. On the older valves made in Italy it wasn't at all possible because the hole in the base had a reduced diameter. But I know people with modern valves with broken stems where the stem could come out the bottom, but it doesn't. Possibly because they pump with the valve at 12:00 and gravity is working for them.

In any case, the OP's valve must still be in place since the tire is holding air. and the WORST case scenario is that she blows it into the tube, and has to replace the tube. Until then it will hold air, so the choice is whether to replace the tube now, to avoid having to replace it alter, or to wait until she has to replace it. As I see it, she has nothing to lose by waiting, and with any luck she can use this tube until it flats for another reason.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

Just because I'm tired of arguing, doesn't mean you're right.

“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 09-21-14, 02:01 AM
  #9  
It's MY mountain
 
DiabloScott's Avatar
 
Join Date: Sep 2006
Location: Mt.Diablo
Posts: 10,005

Bikes: Klein, Merckx, Trek

Mentioned: 70 Post(s)
Tagged: 0 Thread(s)
Quoted: 4355 Post(s)
Liked 3,018 Times in 1,637 Posts
Originally Posted by FBinNY
It's kind of funny, folks have been breaking the nut off and pumping their tubulars using Silca pumps daily and I don't know anyone who ever blew the stem into the tube.
So the valves in tubulars are somehow different? I never noticed. It happened to me on a clincher on a century - got a flat, changed the tube, turned out my CO2 inflator wouldn't take my cart so some guy lent me his mini pump and I got it pumped up but when I took off the pump there was just nothing there... like a hollow cylinder. When I got to the rest stop I used the mechanic's pump and then the check valve fell out and the tube wouldn't hold air. So maybe it was something more than just breaking off the little nut, maybe my valve in the spare was flawed to begin with.
DiabloScott is offline  
Old 09-21-14, 07:41 AM
  #10  
Senior Member
 
Looigi's Avatar
 
Join Date: Dec 2010
Posts: 8,951
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
Likes: 0
Liked 13 Times in 12 Posts
Yeah. My experience with presta tubes with broken off nuts is they work until I try to add air. Even with the stem at the top pointed down and trying to pump very slowly the poppet get blown irretrievably into the tube. Of course you might get away with it, or perhaps you have a stem that prevents the poppet from going into the tube, but in stems with non-removable cores the stem has clearance to insert the poppet from the inner end during manufacture.
Looigi is offline  
Old 09-21-14, 09:09 AM
  #11  
Senior Member
 
intransit1217's Avatar
 
Join Date: Jul 2014
Location: Kenosha , Wi
Posts: 1,231

Bikes: 2 Masi giramondo

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 46 Post(s)
Liked 6 Times in 6 Posts
If prestas are the standard, why are they not used on aircraft? Or Busses. or big trucks. or...or...or...

Check to see if your rims can be drilled, change to schraders.
intransit1217 is offline  
Old 09-21-14, 09:36 AM
  #12  
Senior Member
 
rebel1916's Avatar
 
Join Date: Aug 2011
Posts: 3,141
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 68 Post(s)
Liked 84 Times in 45 Posts
Originally Posted by intransit1217
If prestas are the standard, why are they not used on aircraft? Or Busses. or big trucks. or...or...or...

Check to see if your rims can be drilled, change to schraders.
None of those inflate to high pressures on narrow rims for one thing.
rebel1916 is offline  
Old 09-21-14, 09:49 AM
  #13  
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,918

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: 140 Post(s)
Tagged: 1 Thread(s)
Quoted: 5893 Post(s)
Liked 2,755 Times in 1,538 Posts
Originally Posted by intransit1217
If prestas are the standard, why are they not used on aircraft? Or Busses. or big trucks. or...or...or...

Check to see if your rims can be drilled, change to schraders.
Presta valves have 2 advantages uniquely suited to bicycles.

1- the stem is narrower, so they allow for narrower rims. Note that this isn't a rim strength or room to drill issue. It's about the sum of widths of the valve and two tire thicknesses which determine the minimum inside width of the rim's tire flanges.

2- they're springless check valves, which makes them ideally suited for hand pumping, and eliminates the need for a valve depressor in the pump head, and/or air loss when the head is removed. This also simplifies the design and use of the pump heads since they need only provide a seal to the shoulder of the valve.

If either reason applies, Presta is a better choice, otherwise it's a toss up.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

Just because I'm tired of arguing, doesn't mean you're right.

“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 09-21-14, 09:56 AM
  #14  
Senior Member
 
intransit1217's Avatar
 
Join Date: Jul 2014
Location: Kenosha , Wi
Posts: 1,231

Bikes: 2 Masi giramondo

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 46 Post(s)
Liked 6 Times in 6 Posts
Yes. They are perfectly suited for deep V carbon wheels. Yay. Most of us are mortals.

And while they are not narrow wheeled vehicles: Tire Pressure On A 747 — Tech Ops Forum | Airliners.net
intransit1217 is offline  
Old 09-21-14, 09:58 AM
  #15  
Senior Member
 
intransit1217's Avatar
 
Join Date: Jul 2014
Location: Kenosha , Wi
Posts: 1,231

Bikes: 2 Masi giramondo

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 46 Post(s)
Liked 6 Times in 6 Posts
In other words, check with your lbs to see if your rims can handle it and "DRILL BABY DRILL ! "

*presta hayter 4 lyfe*
intransit1217 is offline  
Old 09-21-14, 10:02 AM
  #16  
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,918

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: 140 Post(s)
Tagged: 1 Thread(s)
Quoted: 5893 Post(s)
Liked 2,755 Times in 1,538 Posts
Originally Posted by DiabloScott
So the valves in tubulars are somehow different? I never noticed. .
I don't think it's about tubulars, but the valve maker. Some things were lost in translation when the valve production moved from Italy to the orient. For example ole timers will confirm that BITD it wasn't necessary to "burp" valves before pumping. So there was a change either in the material of the O-ring or the shape of the valve seat (or both). Plus valve separation from the tube was virtually unheard of, and now it's fairly common.

IMO this is a natural consequence of placing the need to squeeze every last mil out of the cost vs. producing a product worth putting your name on. Tubulars were relatively expensive and no maker wanted to have his reputation suffer over bad valves. The same used to be true when folks like Michelin, Continental, and others made their own tires and tubes. These days bicycle tubes are completely generic with the source being the lowest bidder, which moves quality to the back burner.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

Just because I'm tired of arguing, doesn't mean you're right.

“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 09-21-14, 01:46 PM
  #17  
Senior Member
 
Join Date: Sep 2003
Location: Allen, TX
Posts: 1,916

Bikes: Look 585

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 25 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by intransit1217
If prestas are the standard, why are they not used on aircraft? Or Busses. or big trucks. or...or...or...

Check to see if your rims can be drilled, change to schraders.
They are pretty much the standard for bicycles -- the actual context of this discussion. What exactly would be gained by converting the rims to Schrader?
bikepro is offline  
Old 09-21-14, 02:28 PM
  #18  
Senior Member
 
intransit1217's Avatar
 
Join Date: Jul 2014
Location: Kenosha , Wi
Posts: 1,231

Bikes: 2 Masi giramondo

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 46 Post(s)
Liked 6 Times in 6 Posts
In the world of repairs out in the field, it pays to have the most common items available. OR carry everything you need all the time. At the very least, one of those presta adapters, which get lost easily.

Dear Olga:

You have heard from both camps on this. If you can find a situation that's better than either of these presented, take it.

Sincerely,
Rich
intransit1217 is offline  
Old 09-21-14, 02:41 PM
  #19  
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,918

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: 140 Post(s)
Tagged: 1 Thread(s)
Quoted: 5893 Post(s)
Liked 2,755 Times in 1,538 Posts
BTW- whatever plays out with this tube, if you're going to stay with PV, it pays to learn how not to break the nuts off.

Despite pumping thousands of times (maybe 10s of thousands) since, the last PV valve I snapped the nut off was back in 1968 or so.

It's easy to damage valves, including breaking Shrader valves when hand pumping. It's just as easy not to. The difference is in learning basic techniques for fitting pumps, and properly bracing then when hand pumping.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

Just because I'm tired of arguing, doesn't mean you're right.

“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 09-21-14, 02:58 PM
  #20  
Abuse Magnet
 
arex's Avatar
 
Join Date: Jun 2012
Location: Colorado
Posts: 1,870

Bikes: '91 Mtn Tek Vertical, '74 Raleigh Sports, '72 Raleigh Twenty, '84 Univega Gran Turismo, '09 Surly Karate Monkey, '92 Burley Rock-n-Roll, '86 Miyata 310, '76 Raleigh Shopper

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 152 Post(s)
Liked 177 Times in 90 Posts
I don't understand the hate for Presta at all. I've only been using Presta on my bikes for the last few years, but there's no way I'd go back to Schrader. Presta just works better.
arex is offline  
Old 09-21-14, 03:08 PM
  #21  
Senior Member
 
rebel1916's Avatar
 
Join Date: Aug 2011
Posts: 3,141
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 68 Post(s)
Liked 84 Times in 45 Posts
Originally Posted by arex
I don't understand the hate for Presta at all. I've only been using Presta on my bikes for the last few years, but there's no way I'd go back to Schrader. Presta just works better.
Of course it does. And any pump your purchase with which to make
Originally Posted by intransit1217
repairs out in the field
will, of course, deal with Presta just fine. And just in case of a severe emergency that requires pumping quarters into a gas station compressor (perhaps you broke your mini pump fighting off a bear, and expended your CO2 cartridges attempting to do whipits) can be dealt with by throwing a tiny adapter into your saddle bag.
rebel1916 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
mr,grumpy
General Cycling Discussion
5
10-14-17 03:30 PM
bigxbomber11
Bicycle Mechanics
1
05-15-17 12:18 PM
Steve.D
Commuting
25
04-15-14 05:50 AM
bke92
Bicycle Mechanics
6
02-16-14 09:43 AM
vol
Bicycle Mechanics
28
10-15-12 05:24 AM

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

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

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.