Presta Valve Extension Question

[CT Rider]

Looks like I need to get extensions for the Presta valves on my new wheels (I know I should have gotten tubes with longer valves, hindsight is 20/20). As I look at the extensions there seem to be 2 kinds:

1) Extensions which do not seem to have the valve assembly in them. It looks like you put these on as you need them by first loosing the presta valve on the tube, screwing on the extension, inflating and them removing the extension, etc.
2) Extensions which have the presta valve assembly in them. Looks like you loosen the presta valve on the tube and then screw the extensions on permenently.

Question #1: On type 1 am I correct in assumming you screw these on/off only when you need to inflate the tires?
Questions #2: Any major advantages/disadvantadges between the two types, other than the convience of type 2 being installed permenently?

[Sandy]

I really can't answer your questions. But, why don't you simply buy tubes with longer valve stems now? If you have a bunch of tubes with shorter valve stems, then couldn't you exchange them? It seems easier to me to just buy new longer ones than to mess with extensions. Maybe I am oversimplifying the matter.



Simplified Simpleton Sandy

[Jeff Weir]

I've had good results using Tufo valve extenders.

When using them, you remove the valve core form your tubes stem, thread the core into the Tufo extension, screw extension onto tube using plumbers tape.

No fuss, no muss

[Bruce K]

Valve extensions:

1. The hollow ones work pretty well with the valve open inside them. You generally have to use some plumbers tape to seal them properly. I personally don't like the idea of the valve being open as debris or water could find it's way inside.

2. The ones that attach over the existing valve work pretty well. You might need to seal them as well, but generally not as a rule of thumb.

3. There is a third type that replace the valve core in a tube that has removable cores. You then screw the core back into the end of the extension. These work really well but are rather heavy.

4. Using correct length stems saves all the odd issues and their associated aggravation, and in the long run you will probably buy the extensions, use them for a while, and then get long stem tubes anyways. :D :rolleyes:

BK

[CT Rider]

100% Truth in what you say Sandy! Bottom line is a so strapped for time these days I would prefer a quick and simple solution to the problem (I'm also lazy :) ). I do unfortunately have about 8 or so tubes with normal 32mm stems which won't work in either of my wheelsets. Those I will be giving away to my biking buddies who can use them. My future tube purchases will be for long (60mm) stem tubes only. My Kysrium wheelset has the proper long length stems, it's my Litespeed that I use for indoor/bad weather riding that has the wrong tubes. I figure it's only a matter of time (I have bad luck with tubes!) before I need to replace the tubes on the LS, until then extensions would be a nice, quick (and lazy) solution!

[ada@prorider.or]

Looks like I need to get extensions for the Presta valves on my new wheels (I know I should have gotten tubes with longer valves, hindsight is 20/20). As I look at the extensions there seem to be 2 kinds:

1) Extensions which do not seem to have the valve assembly in them. It looks like you put these on as you need them by first loosing the presta valve on the tube, screwing on the extension, inflating and them removing the extension, etc.
2) Extensions which have the presta valve assembly in them. Looks like you loosen the presta valve on the tube and then screw the extensions on permenently.

Question #1: On type 1 am I correct in assumming you screw these on/off only when you need to inflate the tires?
Questions #2: Any major advantages/disadvantadges between the two types, other than the convience of type 2 being installed permenently?

type 1 is the best since the other create a greater disbalance in the wheel
also if you keep that extension with you in your sadle bag you always have it with you
the extensions one side to on screw the valve
the other side to srew it on on inflate the tyre
then unscrew it again and screw the valve down again

altough my experiance is that lots of people leave the extension on
in wich i think its not a good idea specialy when you are decinding a mountain (greater dis balance of the wheel)
but on the other hand only climbing and flat road i can see that its handy to leave it in
altough i never do this
cees

[CT Rider]

I've had good results using Tufo valve extenders.

When using them, you remove the valve core form your tubes stem, thread the core into the Tufo extension, screw extension onto tube using plumbers tape.

Jeff,

I did notice those Tufos. Problem is my Kenda tubes do not have the removeable Presta Core. I'd need to change the tubes to use these, in which case I'd just use longer stem tubes and avoid the extensions all together.

[11.4]

Most clincher tubes don't have removable cores these days, but they do come in longer lengths as noted above. Don't forget to change your spare when you change the ones on your wheels. I've had a number of riding companions on CXP-33's, Ksyriums, etc. who needed a slightly longer stem on their spare and couldn't do a tire change when they realized they hadn't addressed their spare tubes. Me, I just use tubulars, so I can use the tufo extenders if necessary, and they are one of the best solutions available -- there are aluminum and steel versions out there, so you can use the aluminum ones to avoid Cees' issue.

If you leave a removable valve extender on your bike, do be aware that it can vibrate loose and fall off. Then you may not have the ability to pump up a tire. Just for riders I'm on training rides with, I tend to carry a couple different valve extenders (of the type that fit over the existing valve core) -- it's no real weight, and saves the day. I do hate rims that need longer valve stems. For races, it's one thing, but training, I just try to stay with standard length stems.

[ada@prorider.or]

there are aluminum and steel versions out there, so you can use the aluminum ones to avoid Cees' issue.

well of course i do not agree
altough we made very light alu extenders for our wheels
i still do not recommend to leave them on the wheel

if you know how many force it generate's when decending at 80 km/h
you would not want them to stay on your wheel

[Hysbrian]

Cees would this still be an issue if we consider that 90% of the valve is covered by the rim, and the weight could be balanced with a computer magnet.

[ada@prorider.or]

Cees would this still be an issue if we consider that 90% of the valve is covered by the rim, and the weight could be balanced with a computer magnet.

well then you have to balance the wheel on 2 points
the cover of the wheel does only solves the aerodynamic disbalance and disturbance but not its weight

of course you balance dynamicly
but basicly you can see it when it it on a stand lets assume the bearings are adjusted properly and do not interfere the balance
the weight goes in the lowest possition
(at least here in holland)
:banana:

[Argos]

I'm not sure he'll have to many 80kph downhills in CT, but even if he does, wouldn't the valve actually help increase balance as it is oposing the seam of the rim?

[Hysbrian]

If anything I would have thought that the added weight along the rim would make it harder to stop, as you have increase momentium. Kinda the opposite of Mavic drilling down their rims.

[ada@prorider.or]

I'm not sure he'll have to many 80kph downhills in CT, but even if he does, wouldn't the valve actually help increase balance as it is oposing the seam of the rim?

not every wheel is the seam upposite the valve in the rim
and with carbon this getting even more complicated

[Argos]

True but we are talking about aluminum clinchers, not carbon tubbies.

[ada@prorider.or]

True but we are talking about aluminum clinchers, not carbon tubbies.

indeed i have had a lot of alu rims who did not have the seam opposite of the valve hole
on clincher alu rims :banana:

[Argos]

Where are they joined? I would think if we are talking bout balance, this would make the most sense. Though, what makes sense and what people do are two different things.

CTrider,
just for giggles, what type of rims are these?

[CT Rider]

just for giggles, what type of rims are these?

Nothing spectacular, the Litespeed they are on is used for indoor training/bad weather, - Campagnolo Vento Wheelset.