Home > Bike Types > Mountain Bike

Adorn your wheels with Nex-Gen Stem Gems for stronger tubeless valves

11 Comments
Support us! Bikerumor may earn a small commission from affiliate links in this article. Learn More

A tubeless valve stem is a tubeless valve stem, right? Not so fast. When it comes to tubeless valves, Nex-Gen Sports claims that all are not created equal. Rather than being constructed from “thin wall, welded or extruded aluminum tubing,” Nex-Gen Stem Gems are machined from solid bar stock which is just the start…

Nex-Gen Stem Gems tubeless valve strength

 

Starting with cold drawn solid bar stock, Stem Gems are CNC machined and then put through a “multi-stage anti-corrosion process that exceeds both American STM B117 and ISO/DIS 11130/2017 international standards.” Seemingly through their own testing, Nex-Gen claims that their valves are up to 200% stronger when compared with five other brands of extruded valves with similar lengths and identical wall thickness.

Nex-Gen Stem Gems rubber grommet Nex-Gen Stem Gems valve head

To make the sealing components more durable, all of the rubber pieces are removable and replaceable. The ends also feature a 4mm Allen fitting to help tighten them to the rim when first fitting them. Nex-Gen claims the alloy head of the valve stem is specifically engineered to work with their tire sealants without “causing ‘balling’ of the sealant ingredients.”

Nex-Gen Stem Gems weight

Offered in 42, 62, and 95mm valve lengths, actual weights start out at 4.7g for the 42mm valve with the cap. Sold as a pair in all black with a clear cap, the Stem Gems sell for $19.99.

nex-gensports.com

 

Subscribe
Notify of
guest

This site uses Akismet to reduce spam. Learn how your comment data is processed.

11 Comments
Oldest
Newest Most Voted
Inline Feedbacks
View all comments
mud
mud
2 years ago

the air hole might be blocked by tire liners.

SnarkyCharlie
SnarkyCharlie
2 years ago

Finally, a tubeless valve I can install with an impact driver.

fr0hickey
fr0hickey
2 years ago

I use Stan’s Notubes brass tubeless valves. Likely stronger than aluminum, but heavier too.

Seraph
Seraph
2 years ago

I use Stan’s regular alloy valves. Never had an issue with them. I’m not sure that tubeless valves is a great place to try to innovate.

syborg
syborg
2 years ago

Had to read the article to find out what a vavles is.

J Jones
J Jones
2 years ago

Absolutely nothing new. The VAST majority of valves are also machined from billet so that’s a hollow claim, made against mystery brands. Many many valves have removable seals and the balling of sealant has nothing to do with the metal, it’s a result of the chemistry of individual sealant and not an interaction with an anodized surface.

Tom
Tom
2 years ago

In my limited experience, strength of the valve stem is not an issue. Clogging of the valve seat is, but its endemic with this type of valve with sealant. Boutique item that offers no advantage, in search of your cash.

Yerma
Yerma
2 years ago
Reply to  Tom

This. If someone invents a clog-proof valve stem I’m all in.

Chris Stenger
Chris Stenger
2 years ago

Its the inner valve parts bending that they need to fix IMO.. (the skinny threaded part) i always start bending them and then you can’t close the valve as good and you loose a tiny bit of air…

Hal
Hal
2 years ago
Reply to  Chris Stenger

You can buy quality replacements pretty cheaply/easily for this issue!

Crash Bandicoot
Crash Bandicoot
2 years ago

Hmm interesting, I always go Chinese anodized ones on ebay and have never had an issues. When I did the brass ones I’d throw them in the ultrasonic cleaner for a few minutes and the congealed sealant was no more. Pro tip, once you can’t patch your road tubes anymore, extract the valve stem. Been doing that for years and have never had to buy a valve stem.

Subscribe Now

Sign up to receive BikeRumor content direct to your inbox.

Subscribe Now

Sign up to receive BikeRumor content direct to your inbox.