I just glued some tubular tires with some valve extenders (problem solvers 50mm), the ones that just screw onto the valve. When I went to inflate the tire with my Wrench Force floor pump, I wasn’t able to “lock” the nozzle onto the valve extender; it kept popping off whenever I got about 60-70 psi into the tires. This leads me to believe that the pump is in fact transferring air to the tire, but I can’t get enough air into the tire before the pump flies off.
Any suggestions? Should I just get some different valve extenders maybe? Or am I doing something wrong? (it’s my first time gluing, and my first time using valve extenders.)
Did you remove the valve cores from your tire before installing the Problem Solvers 50mm extensions? I googled that product and it looks like it screws on over the resident valve core. If you installed them over the existing valve cores, are you sure that they are fully open?
I did not remove the valve core. I am sure that the valve is fully open. Basically I can only get about 60psi, and then the pressure is too much and the nozzle pops off.
I know exactly what you are talking about - had the same problem with some ones I got from Hed. It’s like the end of the valve stem isn’t grippy enough to hold the pump head on. What I did at first was have my wife hold it on while I pumped (that sounds dirtier than it really was supposed to). After a couple of years she got tired of doing that, so I started applying things to the end of the valves to make them grippier. Do not try electrical tape, duct tape, or taking a thin file to them to give them ridges - none of those worked. What did work was painting the outside of the valve stem with rubber cement and letting it dry for a few days. Pump never came off again. Then I sold the wheels. Wonder how that guy is doing with them. Come to think of it, you didn’t buy them second hand from a guy in Florida, did you?
Haha, well I just tried two things. One was the “third hand” trick. I got to 80psi before my “third hand” bailed on account of the “plastic expanding” in the nozzle. We switched roles and I did feel that the nozzle was on the verge of bursting.
The second thing I tried was mounting the valve extender on an unmounted tubular, with plenty of teflon tape, in case the key variable here is the fact that I have already mounted these tires on some deep-dish rims (meaning it’s a bit difficult to access the original valve). Again, I got to 80psi and then the nozzle blew off.
I will try the rubber cement idea if the bike shop that sold me the extenders doesn’t have any suggestions, and nothing else works.
Maybe I should just get some extenders that also replace the valve core?
I removed the valve core, and put a very liberal amount of teflon tape around the seam where the core screws into the valve stem and around the seam where the extender screws onto the valve core.
I applied a similarly liberal amount of teflon tape around the tip of the valve extender.
This allowed me to pump up both my tires to 125 psi, without the nozzle flying off, and without any leakage between the extender and the valve. Hopefully these applications of teflon tape will hold for a while!
It looks like a wet cigarette stuffed into your wheel.
As Marty found, teflon tape is the magic trick.
For future reference, when you initially mount the tires to stretch them out before you glue them, test out the inflation. You do stretch the tires before you try to glue them, right?
The extender tucks in after inflating so the tape over the hole fits smoothly.
As you can see in the picture I use clinchers now. Michelin Pro Race - although latest test by Al shows Bontrager clincher RXL Pro 23 with latex tube has an excellent rolling resistance.
I probably won’t switch soon though since I have good ‘no flat’ experience with Michelin. I will try the new Michelin Pro Race 3 since it is a bit lighter than the 2.
I used tubulars for many years (even for training) and had an old rim to mount the tire inflated to max pressure - at least overnight - before glueing and mounting on the regular wheel.
The overnight or longer stretch makes it a lot easier to mount. Also carrying a used tubular - not a new one - is a must for a spare - or you will have a difficult time mounting it with sweaty hands if flating in a race.
