Nex-Gen off road Ultra-Sealant has some big claims and even bigger active temperature range

Nex-Gen is a company that you may not be familiar with, but if you take a glance at their site, you’ll see the company has big plans for the cycling world. Handlebars, chain lube, 3-D printed saddles, and much more are on the “Coming Soon” side. Their new Ultra Sealant, “a custom synthetic off-road sealant specifically formulated for high volume, low-pressure tires,” is the company’s solution for tubeless tires. The idea sounds great, but what is it, and how can it claim to be better than the existing solutions?

Ultra-Sealant: What does this mean?

The description is pretty vague, but the tech docs claim the new Nex-Gen sealant can seal up holes up to 6mm — that’s solid for sure. Another very promising claim is the climate range of the sealant. Nex-Gen states the Ultra-Sealant stays active and does its job in temperature ranges from -15°C <> 80°C / -5°F <> 176°F, with a shelf life of greater than 12 months.

What’s the formula?

Much like anyone in the chemical world, Nex-Gen isn’t giving out the secret recipe, but the company states in its marketing, “why do sealant brands expect you to use decades-old latex sealants?” Making us wonder if this is a latex-based sealant with an updated formula or something new, along the lines of the Finish Line Sealant.

The super long shelf life supports the idea of non-latex based. The difference being latex sealants use the natural coagulation properties of the compound to stop punctures. The latex coats the area after many passes, and the air escaping stops — it works well, which is why most sealants are latex-based.

Non-latex-based sealants require no change to occur within the tire; these sealants have larger particles that can physically plug the puncture without the aid of latex as a binder. This non-active ingredient (for lack of a better term) gives the non-latex options a much better shelf life but results in less optimal sealing power in our past experience.

Nex-Gen also states this is a high-volume, low-pressure sealant meant for mountain bikes, fat bikes, and anything running something wider than a drop bar. So, does that rule it out or make it less practical for use on the road? We’re guessing no, as many sealants previously were formulated for “off-road use” and eventually saw tarmac-time. Though the industry is quickly coming up with solutions to road tubeless and high-pressure specific sealants are on the market like Specialized’ Rapid Air sealant.

Availability and pricing

The Nex-Gen Ultra-Sealant is available for purchase on the company’s website, along with other gear to outfit and clean your bike. The going rate for Ultra-Sealant is $14 for a 150ml and $30 for a 500ml pack. Nex-Gen suggests on their site that 150ml of Ultra-Sealant will provide adequate protection to a singular fat bike tire.

Long term environmental impact

Nex-Gen also states the new Ultra-Sealant is 100% toxin-free and is safe to use in any environment. Many sealants make this claim, so the real question is — does it work? Some sealants like Rene Herse/Panaracer go as far as to use ground-up walnut shells to ensure the environmental responsibility of their sealant. Yet, without comment from Nex-Gen, we can’t verify the environmental impact of its sealant, though the claims sound promising.

Does it work as claimed?

We’ve reached out to Nex-Gen for some samples to put up against the bike shop standards and will report back with our results. For those interested in trying some out now, you can purchase Ultra-Sealant on the Nex-Gen site.