Dynamic

I have the new Zipp valve extenders on my wheelset (XRP 50mm) that I just got back from a friend who glued it for me.
I put the pump on the extender and tried pumping but it does nothing. Am I missing something?

Mr. Beanz

I have another model with instructions saying to place teflon tape on the threads. I've tried it both way. Without the tape, it's nearly impossible. I've seen other models with a teflon piece installed.

merlinextraligh

the valve gets sticky. (I'm assuming you screwed the valve open befor you put on the extender.)
Without the valve extender, you would just tap the top of the presta valve to bust through that tendency to stick shut.

Since you can't do that, there are 2 answers. 1) pump with so much pressure it busts the valve open (Silca Track Pump helps.) or 2) take something skinny and stick it in the valve extender to push the valve open. Wooden shiskabob skewers are cheap, work well, and make for good cookouts.

woodduck

being 50mm, you should be able to unscrew the valve extender and get to the vavle through the hole in the rim. Depending on your tubulars, the vevle should be just under the rim and not too far to get to.

take a very small screw driver or tweezers and unsrew the vavle pin, try to really get it stuck open before you screw the extender back on.

Also like they said, sometimes it takes a lot of pressure to pop the vavle.

Happens on my track wheels every other week.

Dynamic

ok so Im going to try the teflon I think.

oddly enough, I can pump but I hear a lot of air leaking from the valve as well.
I only managed to get it to around 105 psi on the front and 90 in the back.

DPN

The Tufo extenders use the valve core from your tire, and place it where it normally would be...


DPN