Long valves on deep rim wheels!!!

rubs

Hi all,

Just wondering did anybody have a solution to a re-occuring problem that i keep having with a pair of 808`s. They are tubs, and after every couple of spins they need pumping....but it takes an age of messing about with skinny allen keys trying to release the valve, etc...any ideas??...front seems to be a lot worse than rear wheel for some reason...driving me f**king mad so it is:mad:

Doc_Savage

would valve extenders not be of any use? basically just a tube that screws on and "extends" the length of the valve.

blorg

I don't have rims that deep but on my Cosmics I use valve extensions where you remove the core from the actual tube valve and re-screw it into the end of the extenstion. So it works just like a normal presta valve. Obviously with 808s you would need longer extensions but other than that the principle is the same.

rubs

thanks guys but I should have been clearer...I have the extended plastic covers but the problem is that the valve seems to get jammed so I have to wiggle about a slim allen key to try and free it up...real hit and miss....

Am I doing something wrong or is this a normal occurence....first set of real deep rims so a bit "green"

cheers

IM0

rubs wrote: »

Hi all,

Just wondering did anybody have a solution to a re-occuring problem that i keep having with a pair of 808`s....any ideas??...

get your mechanic to do it, or else fire him and get a new one who will.

quintana2

rubs wrote: »

thanks guys but I should have been clearer...I have the extended plastic covers but the problem is that the valve seems to get jammed so I have to wiggle about a slim allen key to try and free it up...real hit and miss....

Am I doing something wrong or is this a normal occurence....first set of real deep rims so a bit "green"

cheers

Ihave the same problem with 808s the zipp extenders that come with them are basically s**t. vittoria have new long valve extenders up to 110mm which will fit 808s

Doc_Savage

this actually sounds like a pump issue.... have you tried changing tubes/tyres?

tubes sometimes need a "kick" to open the presta valve and allow the pressure in the pump to equal that of the inner tube....

sounds simple i know... but happened when i had maxxis inner tubes. i got a new pump, and it requires far less of an initial pump to get going!

if this sounds likely then just give that first pump a bit of welly!

tunney

Are they the valve extenders that screw over the existing value?
Or are they the ones that replace the valve that comes with them?

If the former then did you put plumbers tape on the valve before screwing on the extender? If not then it seems like the pressure in the extender can't build up to the required amount to depress the valve head and let the air go in.

biker_joe

have you tried the top peak valve extenders.... I have used a good few types of extenders on my 60mm rims, and these are the best for getting the pressure up !

http://www.chainreactioncycles.com/Models.aspx?PartnerID=79&ModelID=7356

Joe

blorg

@Joe- can you remove the valve core and re-thread it into those extenders? Do you know if that price is for a pair or one extender?

biker_joe

Hey Blorg
That's the price for one, these are the type that screw on the the existing valve, they have a rubber seal at the bottom and use the same push in valve system at the top ( the silver part ) so they are very good at maintaining the pressure .....
I also bought vittoria valve extenders ( they come in pairs ) that are that permantantly screwed into an existing tubes valve stem, but could n't get tubes to have re-movable core ??? Where can these be got ????

Joe.