Stem Gem Valves

(4 customer reviews)

$19.99

The new standard in hi-quality tubeless valves.
Machined from solid alloy bar.
From 4.7 gms/pc
Three lengths available – 42mm, 62mm & 95 mm
Sold in pairs.

SKU: N/A Categories: , , ,

STEM GEMS
• 3 lengths available – 42mm, 62mm and 95mm
• From 4.7 gms each including cap
• Sold per pair
• Color – Black only including Presta valve
• Solid bar construction – Not tubing
• Hard plated corrosion resistant
• Removable, replaceable components
• 4mm Allen key compatible (not supplied)

WARRANTY
5 years unconditional.


All Stem Gems are sold at 19.99/set inc free shipping within continental USA

Additional information

Weight 0.115 kg
Dimensions 10 × 10 × 20 cm
Select valve length

42mm, 62mm, 95mm

Tech talk

THE COMMON TUBELESS VALVE STEM

With the recent uptake of tubeless tire/rim combinations now gaining increasing favor over traditional rubber / butyl / latex inner tubes across the general cycling population (Professional road cyclists still currently prefer glued-on tubular tires for various reasons), the humble tubeless valve stem has become a necessity.

But as with most things in life – Not all tubeless valve stems are created equal!

The vast majority of commonly available valve stems are manufactured from thin wall, welded or extruded aluminum tubing which is then thread cut both internally to accept the industry standard Presta valve core and externally for the rim locking nut.

Brass valve stems also exist but are generally significantly heavier when compared to the same length in alloy.

Most alloy stems undergo various types of colour anodising which provide some degree of corrosion resistance and improved aesthetic appearance.

With many stems the rubber, usually V-shaped, inner rim seal is either bonded or pressed on to the alloy shaft and cannot be replaced.

tubeless valve

PROBLEMS

Such mass-produced stems often corrode under harsh climatic conditions, are prone to air leakage if precise machining tolerances are not met and can often fail when either the rubber seal becomes dislodged or the stem itself snaps – Usually during tire inflation.

Nex-Gen tubeless valve are machined on high-precision equipment using solid bar stock. Following stringent QC checks each valve stem undergoes a multi-stage anti-corrosion process that exceeds both American STM B117 and ISO/DIS 11130/2017 international standards.

Nex-Gen rubber components are very specific in shape and function to achieve ultimate performance.
All parts are removable and replaceable if required.

best tubeless valves

The alloy head of the Nex-Gen stem is specifically designed to work with Nex-Gen tire sealants that benefit from gradual and constant mixing when in use, but without causing ‘balling’ of sealant ingredients.

The Nex-Gen 95mm valve stem sectioned to show equal and consistent wall thickness throughout the entire length.

section stemgem

Compare this to your current extruded tube valve if you dare!

 
best tubeless valves

This table compares Nex-Gen 62mm Stem Gem bending / breaking force with 5 other brands of extruded tube valves of similar length and identical wall thickness.

Stem Gems are up to 200% stronger!

 

4 reviews for Stem Gem Valves

  1. Avatar for Jeff

    Ed

    My previous valves corroded from the inside – Thanks Stans! As an engineer I can see the quality in these Nex-gen replacements. Unbelievable for the low price. Highly recommended to anyone going tubeless who wants quality. Ed – CA

  2. Avatar for Jeff

    Wichlinski -Tx

    Got these in the post within 3 days or ordering. Instantly can see the great quality engineering compared to my previous stems. Great product for the low price – Highly recommended tubeless setup.

  3. Avatar for Jeff

    J.Brecker AZ

    Great product, beautifuly engineered and very decent price for what you get. Highly recommended!

  4. Avatar for Jeff

    JKee – Tx

    Great products, even better low price for the quality. Arrived in the post within 3 days or ordering!

Add a review

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4 reviews for Stem Gem Valves

  1. Avatar for Jeff

    Ed

    My previous valves corroded from the inside – Thanks Stans! As an engineer I can see the quality in these Nex-gen replacements. Unbelievable for the low price. Highly recommended to anyone going tubeless who wants quality. Ed – CA

  2. Avatar for Jeff

    Wichlinski -Tx

    Got these in the post within 3 days or ordering. Instantly can see the great quality engineering compared to my previous stems. Great product for the low price – Highly recommended tubeless setup.

  3. Avatar for Jeff

    J.Brecker AZ

    Great product, beautifuly engineered and very decent price for what you get. Highly recommended!

  4. Avatar for Jeff

    JKee – Tx

    Great products, even better low price for the quality. Arrived in the post within 3 days or ordering!

Add a review

Your email address will not be published. Required fields are marked *