Help--Tubeless valve stem pops out

[Onno]

I did my first ride on a new wheel with tubeless tire yesterday, and my ride was cut short when the Stans Valve Stem popped loose--that is, the air pressure pushed the stem through the inner side of the rim, breaking the seal, and letting all the air out. I couldn't get the stem out of the rim entirely to put a tube in, so had to call a friend to pick me up. Embarrassing! I got the stem out later by using a sharp narrow knife to cut away a bit of the rubber base of the stem so that I could push it back through the rim.

The rim is a DT 460, and it seems that the rubber flange at the base of the Stans valve stem is just too narrow for the hole on the inside of the rim. Is this a common problem with tubeless wheel setups? What stem should I try now, or should I just give up and keep a tube in it?

[Vinci]

I haven't run into that with my carbon rims, nor has my buddy on his Pacenti SL23's or Velocity A23's. We are using either Stan's valves or Stan's-style valves.

What sort of pressure are you running? I've never heard of high pressure causing that particular problem, but maybe a slightly over-sized valve hole paired with high pressure could do it.

[oldpotatoe]

I did my first ride on a new wheel with tubeless tire yesterday, and my ride was cut short when the Stans Valve Stem popped loose--that is, the air pressure pushed the stem through the inner side of the rim, breaking the seal, and letting all the air out. I couldn't get the stem out of the rim entirely to put a tube in, so had to call a friend to pick me up. Embarrassing! I got the stem out later by using a sharp narrow knife to cut away a bit of the rubber base of the stem so that I could push it back through the rim.

The rim is a DT 460, and it seems that the rubber flange at the base of the Stans valve stem is just too narrow for the hole on the inside of the rim. Is this a common problem with tubeless wheel setups? What stem should I try now, or should I just give up and keep a tube in it?

Orange seal or DT valves, the last probably the best choice for those rims.

[Onno]

I was not using very high pressure--about 90 pounds. The Stans stems do seem to have a narrow flange than the other types I see online.

[Vinci]

That's higher pressure than I run (65-75psi), but it doesn't seem unreasonable.

I can't speak to DT's valves, but I cannot recommend Orange Seal valves. The base on them is not at all like the Stan's (or most others) and I cannot get a good seal with them. Both my buddy and I bought them on our first tubeless forays and we both had to replace them before we could get the wheels setup.

I couldn't be happier with Gredes valves, which I picked up because long tubeless valves are still a little uncommon. They are lightweight, look great, seal perfectly, and have a nice machined lock nut that captures an o-ring so you can tighten the valve down against carbon wheels without damaging them.

[ColonelJLloyd]

I've only used Velocity and Pacenti valves and never run pressures that high. No issues. Never used a DT rim or valve.

I use two passes of tubeless tape and use a small awl to puncture it at the valve hole then press the valve through and tighten really hard by hand only.

[Onno]

May try the American Classics stems. They at least have a metal base (with o-rings) that should prevent this problem.

[ripvanrando]

Orange valve stems twice blasted into the rim on me. Twice on HED Belgium plus rim. Once during install and once on the road where I had to make my first and only call of shame to my son to get me because I could not get the valve stem out in order to put a tube in. Orange valve stems also do not seal well. I prefer Stans.

[jc031699]

Stan's makes a valve stem with an oversized base

http://www.notubes.com/Oversize-44mm-Tubeless-Road-Valve-Stem-Rectangular-Stopper-P896.aspx

Never used it but may be worth a try.