Stan's No Tubes Universal 35mm Mountain Valve Stem
The 35mm tubeless valve stem, which is the length that suits shallow rims - most mountain rims and plenty of shallow gravel ones. The valve does two jobs: it seals against the rim bed through its rubber grommet, and it gives you a way to add sealant without taking the tire off.
What it does
Length is the thing to get right and it is easy to get wrong. The valve has to pass through the rim and leave enough thread proud for the lockring and a pump head; too short on a deep rim and there is nothing to grip, which is the usual reason someone ends up holding a pump on at an angle and tearing the valve.
The conical rubber base is what actually seals, and it seals against the tape - which is why a valve hole should be pierced small rather than cut open. Tighten the lockring firmly by hand; cranking it with pliers distorts the grommet and makes the leak you were trying to prevent.
Fit and compatibility
For shallow-section rims. Deeper road and aero rims want the 44mm. If you are unsure, measure the rim depth rather than guessing.
Buying it from ProWheelBuilder
ProWheelBuilder is an independent wheel builder in Georgia. Stan's No Tubes makes this; we stock it, we use it on the wheels we build, and we will tell you if it is the wrong one for your rim before you buy it.
Warranty
Stan's No Tubes's warranty. Stan's covers aluminum rims for two years against manufacturing defects. Registered carbon wheelsets carry seven years of warranty cover plus lifetime crash replacement, and registration must be completed before a wheelset claim can be made. Crash damage, abuse and normal wear are not warranty items.
ProWheelBuilder. Tools and accessories sit outside ProWheelBuilder's one-year wheel warranty, which applies to the wheels we lace. Cover for this item is the manufacturer's.
Full terms are on our Policies & Warranty page.
Stan's 35mm tubeless valve stem questions
35mm or 44mm?
By rim depth. The valve needs to come through with enough thread for the lockring and a pump head. Shallow rims take the 35mm; deeper sections need the 44mm.
Does it have a removable core?
A removable core is what lets you add sealant through the valve rather than unseating the tire. Tell us how you plan to set the wheels up and we will make sure you have what you need.
How tight should the lockring be?
Firm by hand. Over-tightening distorts the rubber base and causes leaks rather than curing them.
Is ProWheelBuilder the manufacturer of the Stan's No Tubes Universal 35mm Mountain Valve Stem?
No. Stan's No Tubes designs and manufactures it. ProWheelBuilder is an independent wheel builder in Georgia that stocks it and uses it on the wheels we build.
Not sure? Text or leave a voicemail on 470-253-0929 or email info@prowheelbuilder.com — you will be talking to the people who build the wheels.
