Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Singlespeed & Fixed Gear "I still feel that variable gears are only for people over forty-five. Isn't it better to triumph by the strength of your muscles than by the artifice of a derailer? We are getting soft...As for me, give me a fixed gear!"-- Henri Desgrange (31 January 1865 - 16 August 1940)

User Tag List

Closed Thread
 
Thread Tools Search this Thread
Old 03-29-06, 11:08 AM   #26
MacG
don't pedal backwards...
 
MacG's Avatar
 
Join Date: Jul 2005
Location: Minneapolis
Bikes: Surly Long Haul Trucker set up for commuting and loaded touring, old Sekine road frame converted to fixed-gear, various beaters and weird bikes, waiting on the frame for my Surly Big Dummy build
Posts: 754
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by The Fixer
The centrifical force used to "open" my schrader valves when my wheels spun at extreme speeds.
That's impossible. I can't do the math here in my office right now, but you would have to spin your wheels insanely fast to even approach the kind of centripital force required to open the valve. With a schraeder valve, you're fighting both a spring and the air pressure in the tube. I highly doubt you could get the valve to open on it's own with anything short of a NASA vomet comet ride.

There is also no such thing as centrifugal force; just centripital force and conservation of momentum.
MacG is offline  
Old 03-29-06, 11:33 AM   #27
Re-Cycle
<3s bikes
 
Re-Cycle's Avatar
 
Join Date: Dec 2005
Location: CA
Bikes: lots
Posts: 1,054
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I whouldn't want to put 120 psi behind a schraeder valve, but schraeder valves are sure easy to take apart for tube sliming.

BTW I have drilled out presta MTB rims before in order to use schraeder tubes. If you hate presta that bad do the same and be done with it... but I wouldn't.
Re-Cycle is offline  
Old 03-29-06, 11:34 AM   #28
shokhead
05 Roubaix Comp Double
 
Join Date: Dec 2002
Location: So Cal
Bikes: 2012 Trek Madone 6.2
Posts: 4,659
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by hyperRevue
+1 on unthreaded Presta Valves being worlds easier to use than threaded ones.
The hose clamp loves to grab onto those little threads and refuses to let go.
Who makes unthreaded bysides Mich?
shokhead is offline  
Old 03-29-06, 11:37 AM   #29
wangster
MADE IN TAIWAN
 
wangster's Avatar
 
Join Date: Feb 2005
Location: SF
Bikes: Tarmac, Humble, Makino, Schwinn
Posts: 2,438
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
vittoria
wangster is offline  
Old 03-29-06, 12:03 PM   #30
travsi
i don't stop
 
travsi's Avatar
 
Join Date: Mar 2005
Location: basel, switzerland
Bikes: soma rush, giro
Posts: 1,058
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
hutchinson
__________________
velospace
travsi is offline  
Old 03-29-06, 12:10 PM   #31
mattface
Senior Member
Thread Starter
 
mattface's Avatar
 
Join Date: Sep 2005
Location: Montpeculiar, VT
Bikes: Soma Rush, Fuji Cross, Raleigh Technium Mtn Bike, Ross 10 speed with Shimano 600.
Posts: 3,951
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Aeroplane
You can get Presta valves started inflating with just your mouth. It helps when changing a tube on the road.
That IS a good thing. 1 point for Presta. Of course it'a also easy to bump the pin before it's tightened, and let out some air -1.

I don't mind unscrewing Presta valves, but I've had them bend, and 1 broke off. I've got a brand new wrenchforce floor pump, and a teeny Topeak Pocket Rocket. The pocket Rocket is mostly guilty of ripping the stems off, but the floor pump bent and broke one.

Moreover I'm willing to admit I got a ****ty batch of tubes, and I mostly just wanted to spark debate.
mattface is offline  
Old 03-29-06, 12:39 PM   #32
greengnt
Senior Member
 
greengnt's Avatar
 
Join Date: Feb 2006
Bikes:
Posts: 73
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by mattface
That IS a good thing. 1 point for Presta. Of course it'a also easy to bump the pin before it's tightened, and let out some air -1.

I don't mind unscrewing Presta valves, but I've had them bend, and 1 broke off. I've got a brand new wrenchforce floor pump, and a teeny Topeak Pocket Rocket. The pocket Rocket is mostly guilty of ripping the stems off, but the floor pump bent and broke one.

Moreover I'm willing to admit I got a ****ty batch of tubes, and I mostly just wanted to spark debate.

you can start a schraeder tube with your mouth too. put your canine tooth on the valve and press in and exhale with your mouth closed around the valve stem.
greengnt is offline  
Old 03-29-06, 12:58 PM   #33
marqueemoon
or tarckeemoon, depending
 
marqueemoon's Avatar
 
Join Date: Dec 2005
Location: the pesto of cities
Bikes: Davidson Impulse, Merckx Titanium AX, Bruce Gordon Rock & Road, Cross Check custom build, On-One Il Pomino, Shawver Cycles cross, Zion 737, Mercian Vincitore, Brompton S1L, Charge Juicer
Posts: 7,020
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
They both suck.
marqueemoon is offline  
Old 03-29-06, 01:00 PM   #34
shokhead
05 Roubaix Comp Double
 
Join Date: Dec 2002
Location: So Cal
Bikes: 2012 Trek Madone 6.2
Posts: 4,659
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Maybe if they start using those big American stems in the TDF, we will all have a good reason to switch.
shokhead is offline  
Old 03-29-06, 01:08 PM   #35
baxtefer
Cornucopia of Awesomeness
 
baxtefer's Avatar
 
Join Date: Oct 2004
Location: not where i used to be
Bikes:
Posts: 4,847
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
twist, don't yank your pump heads off and you'll save yourself some headaches.
and yeah, frame pumps are guilty of mangling many a stem. try using a floor pump when possible.
baxtefer is offline  
Old 03-29-06, 01:11 PM   #36
mattface
Senior Member
Thread Starter
 
mattface's Avatar
 
Join Date: Sep 2005
Location: Montpeculiar, VT
Bikes: Soma Rush, Fuji Cross, Raleigh Technium Mtn Bike, Ross 10 speed with Shimano 600.
Posts: 3,951
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
OK. I change my original statement" Presta Valves BLOW!
mattface is offline  
Old 03-29-06, 01:14 PM   #37
mattface
Senior Member
Thread Starter
 
mattface's Avatar
 
Join Date: Sep 2005
Location: Montpeculiar, VT
Bikes: Soma Rush, Fuji Cross, Raleigh Technium Mtn Bike, Ross 10 speed with Shimano 600.
Posts: 3,951
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by baxtefer
twist, don't yank your pump heads off and you'll save yourself some headaches.
and yeah, frame pumps are guilty of mangling many a stem. try using a floor pump when possible.
Guilty as charged. I'm a stem yanker.
mattface is offline  
Old 03-29-06, 01:16 PM   #38
pigmode
works for truffles
 
pigmode's Avatar
 
Join Date: Jun 2002
Bikes:
Posts: 2,038
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Haven't had any problems with Presta, they are so prolific why would one question such a standard? Rain? Snow? Unexpected day off?
pigmode is offline  
Old 03-29-06, 01:28 PM   #39
mattface
Senior Member
Thread Starter
 
mattface's Avatar
 
Join Date: Sep 2005
Location: Montpeculiar, VT
Bikes: Soma Rush, Fuji Cross, Raleigh Technium Mtn Bike, Ross 10 speed with Shimano 600.
Posts: 3,951
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by pigmode
Haven't had any problems with Presta, they are so prolific why would one question such a standard? Rain? Snow? Unexpected day off?
yeah... mostly because I was bored.
mattface is offline  
Old 03-29-06, 01:29 PM   #40
SpiderMike
eert a ekil yzarc
 
SpiderMike's Avatar
 
Join Date: Oct 2000
Location: Pasadena TX
Bikes: many bikes
Posts: 2,558
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I like Presta for my fixie and ss commuter. I use Schraeder for my SS MTB, only because it is easier to find 26X2.5 tubes in Schraeder.

Only issue I have with Presta valves.... the valve covers. If anybody found my valve covers let me know
SpiderMike is offline  
Old 03-29-06, 01:37 PM   #41
highpants
Senior Member
 
highpants's Avatar
 
Join Date: Oct 2004
Location: minneapolis
Bikes: iro mark v 48x16 or 15 i think (fixed), surly 1x1 32x16 (free)
Posts: 607
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
i agree wholeheartedly that presta valves can be difficult. i've learned to be very careful and to invest in fancy floor-pumps; so far i've been lucky. used to be i was always thrashing 'em though.
highpants is offline  
Old 03-29-06, 01:38 PM   #42
pigmode
works for truffles
 
pigmode's Avatar
 
Join Date: Jun 2002
Bikes:
Posts: 2,038
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Anyone else uses stem nuts? I use them and keep them semi snug as they make it easier working with the floorpump head. I usually need to repump every 3 days.
pigmode is offline  
Old 03-29-06, 01:38 PM   #43
highpants
Senior Member
 
highpants's Avatar
 
Join Date: Oct 2004
Location: minneapolis
Bikes: iro mark v 48x16 or 15 i think (fixed), surly 1x1 32x16 (free)
Posts: 607
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
i agree wholeheartedly that presta valves can be difficult. i've learned to be very careful and to invest in fancy floor-pumps; so far i've been lucky. used to be i was always thrashing 'em though.
highpants is offline  
Old 03-29-06, 01:41 PM   #44
astrx
anti-sheep
 
astrx's Avatar
 
Join Date: May 2005
Location: pittsburgh
Bikes: generic lugged track frame
Posts: 313
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
two questions
1 why do presta valves have all those threads
2 i heard somewhere that you should not put those black caps on presta, is that true?
astrx is offline  
Old 03-29-06, 01:51 PM   #45
joeprim
Senior Member
 
joeprim's Avatar
 
Join Date: Jan 2002
Location: Northern Neck Tidewater Va.
Bikes:
Posts: 1,688
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by geog_dash
Schraeders seem easier to use and more reliable, based on experience with low pressure mtb and hybrid tires. Anyone used schraeders at 120 psi? Just wondering.
My old '74 Horizon Sentinal had Schraeders and ran around 110 psi. Oh and one of the young girls that rides with me has a bike with schraeders that runs ~ 110psi. The pump I currenly have works better with presta valves. I have had debris rip a schraeder off my MTB. But I really haven't had trouble with either.

Joe
joeprim is offline  
Old 03-29-06, 01:51 PM   #46
joeprim
Senior Member
 
joeprim's Avatar
 
Join Date: Jan 2002
Location: Northern Neck Tidewater Va.
Bikes:
Posts: 1,688
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by geog_dash
Schraeders seem easier to use and more reliable, based on experience with low pressure mtb and hybrid tires. Anyone used schraeders at 120 psi? Just wondering.
My old '74 Horizon Sentinal had Schraeders and ran around 110 psi. Oh and one of the young girls that rides with me has a bike with schraeders that runs ~ 110psi. The pump I currenly have works better with presta valves. I have had debris rip a schraeder off my MTB. But I really haven't had trouble with either.

Joe
joeprim is offline  
Old 03-29-06, 02:54 PM   #47
Aeroplane
jack of one or two trades
 
Aeroplane's Avatar
 
Join Date: Jun 2005
Location: Suburbia, CT
Bikes: Old-ass gearie hardtail MTB, fix-converted Centurion LeMans commuter, SS hardtail monster MTB
Posts: 5,637
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by astrx
two questions
1 why do presta valves have all those threads
So you can secure the valve stem against them rim with the little nut that comes with it. This makes getting the pump head on far, far easier. The reason they are threaded all the way is because rims have varying depths.
Aeroplane is offline  
Old 03-29-06, 02:57 PM   #48
slopvehicle
ass hatchet
 
slopvehicle's Avatar
 
Join Date: Nov 2003
Bikes:
Posts: 1,284
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I bought a set of Suzue / Alex wheels a couple of years back. I noticed they were drilled for Schreder valves after I'd bought Presta tubes for the project-- so I just threw 'em on there anyway.

I didn't have any problems until I started commuting daily on the bike and therefore checking the tire pressure often. After about six months of this, the stem broke in the big, sharp-edged hole. Happened to the other rim too. I finally got some ugly-but-more-functional Schreder tubes and threw 'em on.

And to answer someone's question....I've been running the Schreders at 120 psi without incident.
slopvehicle is offline  
Old 03-29-06, 03:12 PM   #49
pigmode
works for truffles
 
pigmode's Avatar
 
Join Date: Jun 2002
Bikes:
Posts: 2,038
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I run 25 mm tires at 95, and after two days they are down to 88--still rideable.
pigmode is offline  
Old 03-29-06, 03:24 PM   #50
Ill Mitch
Fast and Danger
 
Ill Mitch's Avatar
 
Join Date: Mar 2006
Location: Toronto, Canada
Bikes: A bunch
Posts: 1,056
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
personally I've never had a problam with presta valves.

So what, you have to unscrew a little thing before you pump it up, what's so hard about that?
Ill Mitch is offline  
Closed Thread


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 03:40 AM.