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 12-04-02, 08:25 AM   #1
brennser
Senior Member
Thread Starter
 
Join Date: Apr 2002
Location: Washington DC
Bikes:
Posts: 113
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Presta valve mystery

Ok, so last week I switched to presta valves on the advice of my LBS. This morning when I came downstairs rear wheel was completely flat! I pumped it up again and went about my business - cycled the 10 miles into work.

So my question is.......is this normal? Do presta's spontaneously deflate? Now my basemnent was probably pretty cold last night - would that have caused it?
brennser is offline   Reply With Quote
Old 12-04-02, 08:29 AM   #2
velocipedio
human
 
velocipedio's Avatar
 
Join Date: Jun 2001
Location: living in the moment
Bikes: 2005 Litespeed Teramo, 2000 Marinoni Leggero, 2001 Kona Major Jake (with Campy Centaur), 1997 Specialized S-Works M2, 1992 Specialized Rockhopper
Posts: 3,563
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Did you make sure that the knurled nut at the end of the valve was tightened down?
__________________
when walking, just walk. when sitting, just sit. when riding, just ride. above all, don't wobble.

The Irregular Cycling Club of Montreal
Cycling irregularly since 2002
velocipedio is offline   Reply With Quote
Old 12-04-02, 08:36 AM   #3
pokey
Senior Member
 
Join Date: Jun 2002
Bikes:
Posts: 1,372
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally posted by velocipedio
Did you make sure that the knurled nut at the end of the valve was tightened down?
Actually, it does not have to be tightened down,but doing so prevents accidental discharge, in case it should get bumped.I have valve stem extensions, and leave the nut untightened,no problem.Mine are in an unheated garage.The 'advice' to switch sounds like some kind of applesauce.WHY?, if the Schraders were working....

Last edited by pokey; 12-04-02 at 08:40 AM.
pokey is offline   Reply With Quote
Old 12-04-02, 08:39 AM   #4
velocipedio
human
 
velocipedio's Avatar
 
Join Date: Jun 2001
Location: living in the moment
Bikes: 2005 Litespeed Teramo, 2000 Marinoni Leggero, 2001 Kona Major Jake (with Campy Centaur), 1997 Specialized S-Works M2, 1992 Specialized Rockhopper
Posts: 3,563
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally posted by pokey
Actually, it does not have to be tightened down,but doing so prevents accidental discharge, in case it should get bumped.
That's what I was thinking... that something may have inadvertently pressed the valve piston.
__________________
when walking, just walk. when sitting, just sit. when riding, just ride. above all, don't wobble.

The Irregular Cycling Club of Montreal
Cycling irregularly since 2002
velocipedio is offline   Reply With Quote
Old 12-04-02, 08:42 AM   #5
pokey
Senior Member
 
Join Date: Jun 2002
Bikes:
Posts: 1,372
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally posted by velocipedio

That's what I was thinking... that something may have inadvertently pressed the valve piston.
Any 'rug rats' around?
pokey is offline   Reply With Quote
Old 12-04-02, 08:52 AM   #6
gmason
Senior Member (Retired)
 
gmason's Avatar
 
Join Date: Sep 2001
Location: Great North Woods
Bikes: Vittorio, Centaur triple; Casati Laser Piu, Chorus Triple.
Posts: 2,671
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Or maybe you just got a bad tube.

Cheers...Gary
gmason is offline   Reply With Quote
Old 12-04-02, 08:57 AM   #7
nathank
cycle-powered
 
nathank's Avatar
 
Join Date: Mar 2002
Location: Munich Germany (formerly Portland OR, Texas)
Bikes: '02 Specialized FSR, '03 RM Slayer, '99 Raleigh R700, '97 Norco hartail, '89 Stumpjumper
Posts: 1,848
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
So my question is.......is this normal? Do presta's spontaneously deflate? Now my basemnent was probably pretty cold last night - would that have caused it?
not normal. as the guys above have postulated...

Presta's - easier to pump up with a hand pump
Schraeder's - can pump up at the gas station

otherwise, there's not a whole lot of difference.

i have mostly prestas on my 4 bikes. the only problem i sometimes have is that the valve stem sometimes rips out of the tube a little too easily - i've done it while pumping before. maybe i just had some cheap tubes...

the low temperature shouldn't make THAT much of a difference and it will "reinflate" as you ride and warm the air in the tire a little or bring it inside.
nathank is offline   Reply With Quote
Old 12-04-02, 11:06 AM   #8
brennser
Senior Member
Thread Starter
 
Join Date: Apr 2002
Location: Washington DC
Bikes:
Posts: 113
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks for the replies

Schraders weren't working - I was getting lots of flats - then again this is not an auspicious start for the Presta's (less than 100 miles)

yes the little valve was tightened

there is a rug rat but she doesn't get into the basement

maybe it is a bad tube - I just checked the bike in my office and the tire is getting softer - must be a really slow puncture or something to get me 10 miles to work with no noticeable loss in pressure.....

anyhoo I have a spare tube in my bag - I guess I'll fix it before I leave the office and hope I don't get another flat on this freezing DC day
brennser is offline   Reply With Quote
Old 12-04-02, 11:27 AM   #9
pokey
Senior Member
 
Join Date: Jun 2002
Bikes:
Posts: 1,372
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally posted by brennser
Thanks for the replies

Schraders weren't working - I was getting lots of flats -
Prestas get lots of flats too.Best partial remedy is flat resistant tires.
pokey is offline   Reply With Quote
Old 12-04-02, 12:40 PM   #10
Maelstrom 
Wood Licker
 
Maelstrom's Avatar
 
Join Date: Apr 2002
Location: Whistler,BC
Bikes: Transition Dirtbag, Kona Roast 2002 and specialized BMX
Posts: 16,885
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Well seems I am the only one. I have owned 5 presta valve tubes and hate them all. They all popped around the valve WAYYY too easily. If you can't be a little rough then they are useless to me.
Maelstrom is offline   Reply With Quote
Old 12-04-02, 01:03 PM   #11
pokey
Senior Member
 
Join Date: Jun 2002
Bikes:
Posts: 1,372
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally posted by Maelstrom
Well seems I am the only one. I have owned 5 presta valve tubes and hate them all. They all popped around the valve WAYYY too easily. If you can't be a little rough then they are useless to me.
That would suggest you are doing something wrong.No problem here.
pokey is offline   Reply With Quote
Old 12-04-02, 04:22 PM   #12
tFUnK
Senior Member
 
Join Date: Jun 2002
Location: Menlo Park, CA
Bikes: GT Forte Ti, Ridley XBow, Specialized Tricross Sport, Specialized Langster, Xootr Swift
Posts: 2,278
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
a little OT but is it advisable to use presta valves on a schraeder drilled rim?
tFUnK is offline   Reply With Quote
Old 12-04-02, 04:55 PM   #13
pokey
Senior Member
 
Join Date: Jun 2002
Bikes:
Posts: 1,372
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally posted by tFUnK
a little OT but is it advisable to use presta valves on a schraeder drilled rim?
Usually no prob,,but there could be with really high pressure tires where the pressure could force the tube into the larger gap where the stem goes thru the rim,but there are gromets that make them fit better and fill the gap.
pokey is offline   Reply With Quote
Old 12-04-02, 05:07 PM   #14
ngateguy
Center of the Universe
 
ngateguy's Avatar
 
Join Date: Jul 2002
Location: Everett, WA
Bikes: Bianchi San Remo, Norvara Intrepid MTB , Softride Solo 700
Posts: 4,372
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Quote:
Originally posted by pokey
Prestas get lots of flats too.Best partial remedy is flat resistant tires.
Or Mr Tuffys, they are worth the investmant over 3 years not a single flat You do have to be careful with presta valves they are easy to snap then they don't hold air make sure when using a hand pump that you hold the valve securely with your hand
__________________
Matthew 6
ngateguy is offline   Reply With Quote
Old 12-04-02, 05:25 PM   #15
KleinMp99
New to bikeforýms.net
 
Join Date: Jan 2001
Bikes:
Posts: 2,202
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You have to screw down the nut on the end of a presta valve or it could leak slowly.......
KleinMp99 is offline   Reply With Quote
Old 12-04-02, 07:21 PM   #16
Maelstrom 
Wood Licker
 
Maelstrom's Avatar
 
Join Date: Apr 2002
Location: Whistler,BC
Bikes: Transition Dirtbag, Kona Roast 2002 and specialized BMX
Posts: 16,885
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally posted by pokey
That would suggest you are doing something wrong.No problem here.
Oh I know I was doing something wrong. I would pump using a hand pump (oh boy easier to pump but it sucks if you are in a rush which I always am). I would rather have a valve that doesn't break under human strength. I am not a gentle person and don't care to be for the sake of a valve.
Maelstrom is offline   Reply With Quote
Old 12-05-02, 04:39 AM   #17
gmason
Senior Member (Retired)
 
gmason's Avatar
 
Join Date: Sep 2001
Location: Great North Woods
Bikes: Vittorio, Centaur triple; Casati Laser Piu, Chorus Triple.
Posts: 2,671
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
If you can't be a little rough then they are useless to me.
Yeah, that was the problem with all of my Faberge eggs, so I dumped them.

Quote:
I would rather have a valve that doesn't break under human strength. I am not a gentle person and don't care to be for the sake of a valve.
Aside from the somewhat unreal sense of that comment, it is very easy to break a valve of any kind if you do not keep the valve from moving a lot at the rim. Usually holding the pump head, valve, and rim together will suffice.

OTOH, you might be able to find a stainless steel tube somewhere.

Cheers...Gary
gmason is offline   Reply With Quote
Old 12-05-02, 06:09 AM   #18
Davet
Licensed Bike Geek
 
Davet's Avatar
 
Join Date: Oct 2002
Location: Los Barriles, Baja Sur, Mexico
Bikes: Kirk Terraplane, Serotta Ottrott, Spectrum Super Custom, Hampsten Carbon Leger Tournesol
Posts: 1,065
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Presta valves are as tough as Schraeder valves, but they are different and require a different technique when handling them. If you insist on trying to 'beat them into submission' they aren't going to work for you.
Davet is offline   Reply With Quote
Old 12-05-02, 06:32 AM   #19
roadbuzz
Just ride.
 
roadbuzz's Avatar
 
Join Date: Oct 2000
Location: C-ville, Va
Bikes:
Posts: 3,246
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally posted by pokey
Usually no prob,,but there could be with really high pressure tires where the pressure could force the tube into the larger gap where the stem goes thru the rim,but there are gromets that make them fit better and fill the gap.
This is one of my more common tube failures even w/my rims drilled for prestas. Presta pump heads generally fit pretty snugly, and it's easy to damage the stem/tube right at the hole while removing the pump head.
roadbuzz is offline   Reply With Quote
Old 12-05-02, 07:24 AM   #20
chewa
The Flying Scot
 
chewa's Avatar
 
Join Date: Aug 2001
Location: North Queensferry Scotland and London (and France)
Bikes: Custom (Colin Laing) 531c fast tourer/audax, 1964 Flying Scot Continental, 1995 Cinelli Supercorsa, Holdsworth Mistral single speed, Dahon Speed 6 (folder), Micmo Sirocco and a few more
Posts: 1,902
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
You don't need to screw the knurled bit down as the pressure should keep the valve closed (the valve could be defective however, and it does prevent accidental deflation).

The comment that you had a lot of punctures with Schraeders and now have with Prestas suggests either you are installing incorrectly or that maybe your rim tape isn't right.

i've used Prestas for about 25 years and no real puncture problems, other than occasionally them letting go at the valve to tube junction if overpressurized.
__________________
plus je vois les hommes, plus j'admire les chiens

1985 Sandy Gilchrist-Colin Laing built 531c Audax/fast tourer.
1964 Flying Scot Continental (531)
1995 Cinelli Supercorsa (Columbus SLX)
1980s Holdsworth Mistral fixed (531)
2005 Dahon Speed 6 (folder)
(YES I LIKE STEEL)
2008 Viking Saratoga tandem
2008 Micmo Sirocco Hybrid (aluminium!)
2012 BTwin Rockrider 8.1
chewa is offline   Reply With Quote
Old 12-05-02, 02:03 PM   #21
Maelstrom 
Wood Licker
 
Maelstrom's Avatar
 
Join Date: Apr 2002
Location: Whistler,BC
Bikes: Transition Dirtbag, Kona Roast 2002 and specialized BMX
Posts: 16,885
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally posted by gmason


Yeah, that was the problem with all of my Faberge eggs, so I dumped them.



Aside from the somewhat unreal sense of that comment, it is very easy to break a valve of any kind if you do not keep the valve from moving a lot at the rim. Usually holding the pump head, valve, and rim together will suffice.

OTOH, you might be able to find a stainless steel tube somewhere.

Cheers...Gary
I don't get the first comment.

As for the second. I don't agree. I have been commuting for a long time and have never broken regular valve (and until this year have never owned a floor pump). I bought my current mtb in the spring and it came with these presta valves. Cool, something new. (not new but new to me) two bikes, 4 wheels, 4 pops all with a handpump in a matter of 2 weeks.

So there are two option. 1 - Did my bke come with the worst presta valves on the planet causing mine and my cousins (I didn't do these ones but he broke 2 as well) to break under what I consider 'normal' pumping action.? Or do presta valves blow...hmmmm...
Maelstrom is offline   Reply With Quote
Old 12-05-02, 09:42 PM   #22
ngateguy
Center of the Universe
 
ngateguy's Avatar
 
Join Date: Jul 2002
Location: Everett, WA
Bikes: Bianchi San Remo, Norvara Intrepid MTB , Softride Solo 700
Posts: 4,372
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
I agree with Davet presta and schraders are about the same strength wise. when I had schraders I used to carry spare cores for when I broke one, I guess that is one advantage to them you can replace the core without replacing the tube. Prestas on the other hand are easier to control the amount of air pressure. You really should never use a gas station pump to fill your tire it is to easy to blow them up, if you do be careful. And pick up an adapter from you LBS they are usually under a buck and they come in very handy. And Maelstrom remember technique and finesse can be better than brute force

Just this dudes $.02 worth
__________________
Matthew 6
ngateguy 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 10:55 PM.