Are Presta valve caps uncool or what?
02-06-18, 02:18 PM
#126
Senior Member
Join Date: Apr 2011
Location: Alpharetta, GA
Posts: 15,280
Bikes: Nashbar Road
Mentioned: 71 Post(s)
Tagged: 0 Thread(s)
Quoted: 2934 Post(s)
Liked 341 Times
in
228 Posts
Is this what I think it is? Or not, I have not seen one.
Maxxis Presta Valve Stems and Core Removal Tool - Black - Ultimate Cycle Store
Maxxis Presta Valve Stems and Core Removal Tool - Black - Ultimate Cycle Store
02-06-18, 02:34 PM
#127
Tortoise Wins by a Hare!
Join Date: Feb 2006
Location: Looney Tunes, IL
Posts: 7,398
Bikes: Wabi Special FG, Raleigh Roper, Nashbar AL-1, Miyata One Hundred, '70 Schwinn Lemonator and More!!
Mentioned: 22 Post(s)
Tagged: 0 Thread(s)
Quoted: 1549 Post(s)
Liked 941 Times
in
504 Posts
Look at aeronautics. Shape and surface texture are far more important than actual size.
Notice that the threading on a valve closely resembles the fins of an automobile radiator? What is the purpose of an automobile's radiator fins? To catch air.
Bikes with no valve caps are suffering extreme aero penalties, and therefore experiencing significant speed losses.
Again. Any serious cyclist worth his salt (should) understands the performance benefits of a light weight and efficiently shaped valve cap. There are a lot of folks out there with no real understanding of the actual physics involved. It's not their fault. They are neither engineers nor physicists. But don't allow yourself to be fooled by the naive and unsophisticated.
Notice that the threading on a valve closely resembles the fins of an automobile radiator? What is the purpose of an automobile's radiator fins? To catch air.
Bikes with no valve caps are suffering extreme aero penalties, and therefore experiencing significant speed losses.
Again. Any serious cyclist worth his salt (should) understands the performance benefits of a light weight and efficiently shaped valve cap. There are a lot of folks out there with no real understanding of the actual physics involved. It's not their fault. They are neither engineers nor physicists. But don't allow yourself to be fooled by the naive and unsophisticated.
Right. I think the problem here is that those most prone to denying valve cap science do so in other areas as well, like pie plate diameter and kickstand shape... preventing them from ever getting to the speeds required for aerodynamics to be much of a factor.
These are nice, but only appropriate if you run carbon fiber rims.
02-06-18, 02:55 PM
#128
Senior Member
Join Date: Jul 2014
Location: Central Indiana
Posts: 2,159
Mentioned: 27 Post(s)
Tagged: 0 Thread(s)
Quoted: 913 Post(s)
Liked 515 Times
in
344 Posts
Has no one mentioned that a presta valve has two lock nuts? One on each end? Do they cancel each other out when bombing a descent or does one need an opposite side aero reflector. Sooo much science to learn...
02-06-18, 03:06 PM
#129
On Your Left
Join Date: Nov 2011
Location: Long Island, New York, USA
Posts: 8,373
Bikes: Trek Emonda SLR, Sram eTap, Zipp 303
Mentioned: 34 Post(s)
Tagged: 0 Thread(s)
Quoted: 3004 Post(s)
Liked 2,433 Times
in
1,187 Posts
When you run deep carbon wheels, most valve extenders are not threaded so no valve caps.
Personally, I don't run them since they serve no purpose. In 20,000 miles, i've never had a problem leaving them off.
Personally, I don't run them since they serve no purpose. In 20,000 miles, i've never had a problem leaving them off.
02-06-18, 04:24 PM
#130
Senior Member
Join Date: Oct 2015
Posts: 15,489
Bikes: 2015 Workswell 066, 2017 Workswell 093, 2014 Dawes Sheila, 1983 Cannondale 500, 1984 Raleigh Olympian, 2007 Cannondale Rize 4, 2017 Fuji Sportif 1 LE
Mentioned: 144 Post(s)
Tagged: 0 Thread(s)
Quoted: 7652 Post(s)
Liked 3,473 Times
in
1,834 Posts
I'm telling you, get some long-stemmed-tubes and the right caps ....... I'm not saying TdF podium ... but ... Gyro?
02-06-18, 04:28 PM
#131
On Your Left
Join Date: Nov 2011
Location: Long Island, New York, USA
Posts: 8,373
Bikes: Trek Emonda SLR, Sram eTap, Zipp 303
Mentioned: 34 Post(s)
Tagged: 0 Thread(s)
Quoted: 3004 Post(s)
Liked 2,433 Times
in
1,187 Posts
Personally, they serve no purpose so why bother.
As to long stem tubes, I find using Zipp tubes with their extenders are no more expensive, they are not too long and they don't rattle.
02-06-18, 06:35 PM
#133
Senior Member
Join Date: Jan 2016
Posts: 646
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 189 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
The ultimate caps!
How do you like THESE apples?
<1g ea, aero, poorly 3d printed...
<1g ea, aero, poorly 3d printed...
02-06-18, 06:43 PM
#134
Senior Member
Join Date: Apr 2012
Location: Middle Earth (aka IA)
Posts: 20,435
Bikes: A bunch of old bikes and a few new ones
Mentioned: 178 Post(s)
Tagged: 0 Thread(s)
Quoted: 5888 Post(s)
Liked 3,471 Times
in
2,079 Posts
Bike Forums just ain't what it used to be if we can't push this topic up over 10 pages. We haven't begun to scratch the surface when it comes to presta valve caps.
02-06-18, 08:29 PM
#135
Cycleway town
The valve and rim manufacturers need to step up here. We know (from the innertube people) that the locknuts are important but we also all know they sit very poorly on the rime surface (like they are not so important) and scratch that pristine rim surface if tightened enough to stay on through all the vibration a rim gets.
So, get with it! Offer us some properly shaped plastic washers that will fit flush with both the complex curved surface of the rim and the lockwasher. Yes, you will have to provide quite a few variations because rims vary so much, but ... it is you who are telling us this is important. And isn't it your obligation to provide us the means to install these critical parts without damaging the finish of our $1000 wheels? (These washers probably need to have wrench flats so they can be held in proper alignment with the rim. Perhaps a small wrench could be included.)
With these washers, properly installed, we will finally be able to have wheels done right. No gaps under the edges of the lock nuts and no scarred anodizing.
Ben
So, get with it! Offer us some properly shaped plastic washers that will fit flush with both the complex curved surface of the rim and the lockwasher. Yes, you will have to provide quite a few variations because rims vary so much, but ... it is you who are telling us this is important. And isn't it your obligation to provide us the means to install these critical parts without damaging the finish of our $1000 wheels? (These washers probably need to have wrench flats so they can be held in proper alignment with the rim. Perhaps a small wrench could be included.)
With these washers, properly installed, we will finally be able to have wheels done right. No gaps under the edges of the lock nuts and no scarred anodizing.
Ben
02-06-18, 08:38 PM
#136
Cycleway town
This business of the valve hole letting water in has got to be stopped, too. I didn't buy a 24g carbon fibre bottle cage to carry half a pint of rainwater in my rims.
02-06-18, 09:00 PM
#137
Tortoise Wins by a Hare!
Join Date: Feb 2006
Location: Looney Tunes, IL
Posts: 7,398
Bikes: Wabi Special FG, Raleigh Roper, Nashbar AL-1, Miyata One Hundred, '70 Schwinn Lemonator and More!!
Mentioned: 22 Post(s)
Tagged: 0 Thread(s)
Quoted: 1549 Post(s)
Liked 941 Times
in
504 Posts
Needs more bling. Colors? Jewels?
That would mean instant BF bingo.
Great points, both. Almost all of the cyclists I know make these complaints often. (and it's not just the serious cyclists) There's likely a huge market ($$$$) just begging to be tapped here.
That would mean instant BF bingo.
02-06-18, 10:15 PM
#138
Me duelen las nalgas
Join Date: Aug 2015
Location: Texas
Posts: 13,513
Bikes: Centurion Ironman, Trek 5900, Univega Via Carisma, Globe Carmel
Mentioned: 199 Post(s)
Tagged: 0 Thread(s)
Quoted: 4560 Post(s)
Liked 2,802 Times
in
1,800 Posts
Just for giggles, or because I was bored, I emailed a manufacturer of presta valve's and asked them their policy on caps and lock nuts. "Yes. We recommend to use cap. To avoid dust. And recommend to use locknut too. " So all you sloppy unkempt pin bending impaling death machine riding folks are going against manufacturer's recommendations. Good luck with your lawsuit
02-06-18, 10:25 PM
#139
Me duelen las nalgas
Join Date: Aug 2015
Location: Texas
Posts: 13,513
Bikes: Centurion Ironman, Trek 5900, Univega Via Carisma, Globe Carmel
Mentioned: 199 Post(s)
Tagged: 0 Thread(s)
Quoted: 4560 Post(s)
Liked 2,802 Times
in
1,800 Posts
Locknuts don't really work too well with deep-wall rims. They don't sit flush with any rim actually, it's like there's a part missing.
Like a moulded plastic seat, similar in shape to some quick-release compression seats. Or they could at least texture/shape the compression surface of the washer, so that it bites into the alloy. Whatever, this is clearly an area that's seen very little in the way of development.
Like a moulded plastic seat, similar in shape to some quick-release compression seats. Or they could at least texture/shape the compression surface of the washer, so that it bites into the alloy. Whatever, this is clearly an area that's seen very little in the way of development.
Hey, I knew there was a reason why I kept those old concave washers from my worn out linear pull brake pads!
Now I just need to superglue some weights on the opposite side of the rim to counterbalance the extra weight from those washers. I wonder if Wahoo makes a doodad and app to precisely calculate the weight needed three times before the doodad breaks and I switch to a Garmin rim counterbalance weight doodad.
02-07-18, 02:44 AM
#140
Cycleway town
Not a bad effort there. The profile of both the rim and lock nut a touch more advanced than the average effort. But then, so are dinosaur egg nests.
So, get with it! Offer us some properly shaped plastic washers that will fit flush with both the complex curved surface of the rim and the lockwasher. Yes, you will have to provide quite a few variations because rims vary so much, but ... it is you who are telling us this is important. And isn't it your obligation to provide us the means to install these critical parts without damaging the finish of our $1000 wheels?
Ben
Ben
I think there's too much attention being paid to the whole locking thing. You're pulling on rubber, and really, it's only gotta hold the seat of the valve to the rim. We're not talking Stilsons here. The G-force isn't gonna send the valve through the tyre without a locking ring. So we can make the locking ring half the thickness, allowing it to be covered.
Now with the water resistance also in mind, by the time it was daylight this morning, i'd come up with this: What we have here is a corrugated silicone boot. It stretches over any valve type, gripping the valve stem tightly, and forms a tight waterproof seal against even the most challenging deep-wall rims...
Patents pending, or whatever.
02-07-18, 06:08 AM
#141
Advocatus Diaboli
Join Date: Feb 2015
Location: Wherever I am
Posts: 8,636
Bikes: Merlin Cyrene, Nashbar steel CX
Mentioned: 14 Post(s)
Tagged: 1 Thread(s)
Quoted: 4733 Post(s)
Liked 1,532 Times
in
1,003 Posts
To solve this, as well as the locknut seating issue, it seems apparent that rim makes should thread their rim holes, and presta stems should be threaded all the way to the bottom. Yes, might take a few seconds longer to screw your tube all the way into the rim via the valve stem, but worth it for the peace of mind.
02-07-18, 06:19 AM
#142
Senior Member
Join Date: Oct 2015
Posts: 15,489
Bikes: 2015 Workswell 066, 2017 Workswell 093, 2014 Dawes Sheila, 1983 Cannondale 500, 1984 Raleigh Olympian, 2007 Cannondale Rize 4, 2017 Fuji Sportif 1 LE
Mentioned: 144 Post(s)
Tagged: 0 Thread(s)
Quoted: 7652 Post(s)
Liked 3,473 Times
in
1,834 Posts
I think something as convenient and universal somehow has to be combined with something as specific and complex to manufacture as Shafter's effort from post #137 .... and then offered in a variety of colors.
02-07-18, 06:25 AM
#143
Banned.
Join Date: Dec 2017
Location: France
Posts: 1,030
Bikes: Brompton, Time, Bianchi, Jan Janssen, Peugeot
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 598 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
Do not people buy designer valve caps? I usually go for Ralph Lauren or Armani. Never Hilfiger, though, far too brash.
02-07-18, 08:07 AM
#145
Cycleway town
Insufficiently aero .... and too Schraederish. How will it look on longer stems? Well, I guess serious cyclists will machine their stems to leave just enough showing above the rim for a CO2 cartridge inflator--what serious cyclist would use a pump in the 21st century?
I think something as convenient and universal somehow has to be combined with something as specific and complex to manufacture as Shafter's effort from post #137 .... and then offered in a variety of colors.
I think something as convenient and universal somehow has to be combined with something as specific and complex to manufacture as Shafter's effort from post #137 .... and then offered in a variety of colors.
02-07-18, 08:24 AM
#146
Tortoise Wins by a Hare!
Join Date: Feb 2006
Location: Looney Tunes, IL
Posts: 7,398
Bikes: Wabi Special FG, Raleigh Roper, Nashbar AL-1, Miyata One Hundred, '70 Schwinn Lemonator and More!!
Mentioned: 22 Post(s)
Tagged: 0 Thread(s)
Quoted: 1549 Post(s)
Liked 941 Times
in
504 Posts
My only critique is the ugly flat black finish... that's been over played for years now. My preference would be a hi-vis/reflective finish, so I could safely remove my wheel reflectors.
*I'd still like to see the design submitted to an authority on cycle aerodynamics, like professor Squid, for definitive analysis.
02-07-18, 08:41 AM
#147
Senior Member
Join Date: May 2008
Posts: 7,384
Mentioned: 49 Post(s)
Tagged: 0 Thread(s)
Quoted: 800 Post(s)
Liked 218 Times
in
171 Posts
Are Presta valve stem caps uncool or what
All this high tech discussion about valve stem caps reminded me of this product, colorful flashing valve stem lights:
When I bought them, I did think that the utility of such side lighting outweighed the arodynamic drag, and they looked cool. 
Insufficiently aero.... and too Schraederish. How will it look on longer stems? Well, I guess serious cyclists will machine their stems to leave just enough showing above therim for a CO2 cartridge inflator--what serious cyclist would use a pump in the 21st century?
I think something as convenient and universal somehow has to be combined with something as specific and complex to manufacture as Shafter's effort from post#137 .... and then offered in a variety of colors.
I think something as convenient and universal somehow has to be combined with something as specific and complex to manufacture as Shafter's effort from post#137 .... and then offered in a variety of colors.
One set of valve stem lights had the cute name, Tireflies.The problem I have seen with valve lights is that there is no way to easily turn them off during the day to conserve the batteries
Last edited by Jim from Boston; 02-07-18 at 08:54 AM.
02-07-18, 08:44 AM
#148
Senior Member
Join Date: Jan 2009
Location: Colorado Springs, CO
Posts: 5,973
Bikes: 2015 Charge Plug, 2007 Dahon Boardwalk, 1997 Nishiki Blazer, 1984 Nishiki International, 2006 Felt F65, 1989 Dahon Getaway V
Mentioned: 54 Post(s)
Tagged: 0 Thread(s)
Quoted: 1364 Post(s)
Liked 1,677 Times
in
827 Posts
..
02-07-18, 08:49 AM
#149
Registered User
(Look for them at finer cyclists' shops near you!)
02-07-18, 09:10 AM
#150
Senior Member
Join Date: Aug 2011
Location: Toronto
Posts: 1,261
Bikes: Salsa Vaya
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 172 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Good point. The Serious Cyclist crowd should investigate the aerodynamics of paint. I expect that high performance aircraft don't use Plain Ordinary Bicycle Paint and that there are good reasons for that. Perhaps Professor Squid can comment.