View Full Version : Valve stem question
I got a flat (actually, my tire exploded as I was wheeling the bike to the door) last month and used up my last tube. I remember when I bought the tubes the guy at the bike shop asked if I had long or regular stems. I wasn't sure, so I told him what bike I had (Specialized Dolce) and he got me some long stemmed tubes. What's the difference? Are regular stems that much shorter? It just seems harder to find long stem tubes, and they never seem to come in those multi-packs that Performance and other sites have. Can I get away with regular stems?
newfsmith
02-12-2009, 04:48 AM
If your wheels have a deep V, it is harder to get the pump head on the stem if they are the regular length. Not impossible, but frustratingly harder. Long stems are a real advantage if you have to change a tube on a ride.
There are stem extenders you can screw onto regular valves to make them longer. I carry one in my on-bike repair kit just in case you need to use a standard valve in a deep V rim. I wouldn't use this technique on a regular basis, but it could save the day if you're in a pinch.
bike4ever
02-12-2009, 05:35 AM
Generally, there are three valve stem lengths. They often come in 38mm, 48mm, and 60mm. The 60mm are the longer ones. Many shops stop the middle size, but I know we try to keep in stock a small number of the 60mm. I'll be honest, I really have never paid attention to what Performance carries. Since I work in an LBS, online bike companies are taboo.
Thanks for the replies. So in theory I can use a regular length stem, but it just makes inflating it a pain. I have to pick and choose what I get for my LBS. Things are tight, I'm sorry. If I can get 2 or 3 tubes online for the price of one there, I'm going online. I've dumped plenty of money there, it's not like I don't show my face.
bike4ever
02-12-2009, 08:38 AM
NoNo - I'm not knocking shopping on line. I do that for many non-bike purchases. I just was stating that I did not have experience with the Performance product.
OakLeaf
02-12-2009, 08:40 AM
How deep is your rim? I very much doubt if deep aero rims came stock on that bike. 2 cm longer than the depth of your rim is plenty IMO. Especially if you save the little nut that comes with most tubes, that holds the stem in place and makes inflation from zero a whole lot easier. How long is the stem on your old tube? Did it seem okay to you?
You don't want stems that are too long, either. They're heavy, for one thing, harder to carry in your seat pack, and easier to tear off because there's just that much more leverage between the pump head and the tube end. Somebody gave me a long stem tube last year (as a replacement for one I'd given him) and I HATED the thing on my Mavic Aksium rims - stock on my Cannondale Synapse so likely pretty similar to what you have.
Honestly, they seem way too long to me. There's quite a bit of the stem sticking out. I had a hard time believing the regular stems could be that much shorter, but the bike shop made it sound like I HAD to have the long stems. I think I'm going to take the chance and get the regular stems.
Thanks for the replies. So in theory I can use a regular length stem, but it just makes inflating it a pain. I have to pick and choose what I get for my LBS. Things are tight, I'm sorry. If I can get 2 or 3 tubes online for the price of one there, I'm going online. I've dumped plenty of money there, it's not like I don't show my face.
If you need a long stem, then a shorter stem will not work. The pump head simply will not fit far enough onto the stem to inflate the tube. Be sure you have a long enough valve stem before you're on the road with a flat (though carrying a valve extender could save you).
GLC1968
02-12-2009, 12:12 PM
If you need a long stem, then a shorter stem will not work.
I can vouch for that. My wheels aren't super deep V's...but they are deep enough that a regular stem will NOT work at all. It's a pain, but since I always have to carry my own tubes anyway (650's), I just make sure to always buy long stem ones.
I'm at a loss for my new wheels though. They will have the same rims as my other bike, but these are for my bike with the smaller front wheel. I cannot, for the life of me, find 24x1 tubes with long stems. I honestly don't know what I'm going to do if I have the same problem with regular stems that I had on my other bike.
Deb - so those valve extenders are only a temporary solution? Do they make a more permanent version?
Deb - so those valve extenders are only a temporary solution? Do they make a more permanent version?
I've got a Topeak extender, and you have to remove the extender, unscrew the valve, screw the extender back on, and inflate the tire. A pita if you had to do this constantly. But a web search turned up another kinds of valve extender made by Vittoria (other brands available too) where you remove the original valve core, screw on the extender, and then re-install the valve core. So it would work like a normal valve in daily useage, but you need removable-core tubes. You'd need to install this (with a special tool) on your wheels and on your spare tubes, or carry a Topeak extender for the spares.
ridebikeme
02-12-2009, 01:04 PM
If you are using valve extenders without a removable core in your tube, many require that you also use plumbers tape to seal from any air leaking. Yes, it's a pa:)in with 24 x1 tubes.... very difficult to find! Good luck in your search!!
OakLeaf
02-12-2009, 01:21 PM
it's a simple thing to measure...
Those extenders sound interesting. Obviously, I don't want to deal with that kind of hassle all the time. I think what I'll do is pick up one regular length stem and see how it fits. If it's obvious that it would cause an issue, then I'll stick with the longer valve stems. I was just curious if anyone else had given it a try, especially any other Dolce owners. Thanks for all the help, once again I learn something from the TE ladies :)
aicabsolut
02-13-2009, 06:17 AM
48mm is pretty "standard" for a lot of shallow rims (e.g., Shimano wheels, Ksyriums, that might have come on your Dolce). You can go shorter, but it's harder to get the pump on there.
Deep dish wheels will need 60mm or 80mm...or valve extenders, but those suck.
HillSlugger
02-13-2009, 07:50 AM
To me it seems that the longer the stem the more likely that you might tear it off while pumping up your tires (increased torque/leverage). I like to use the shortest stem that works with my rims. I've got 25mm aero rims on my bikes and the 48mm valves work great with my pumps
GLC1968
02-13-2009, 08:09 AM
Oh, I meant to mention that I used to have a Dolce Comp (2006) and it worked with regular length stems just fine on the stock wheels.
Oooh, that's very helpful. Mine's also an 06, with the stock Alex ALX 298 rims. Thanks!
Powered by vBulletin® Version 4.2.2 Copyright © 2025 vBulletin Solutions, Inc. All rights reserved.