Reserve Wheels has released a new tubeless valve system that permits a higher air flow than the ubiquitously used Presta Valve. On the outside, the Reserve Fillmore doesn’t look too dissimilar to the Presta Valve that has seen over a century of use. Internally, it couldn’t be more different. It lacks a removable core, increasing the internal volume of the valve stem. Reserve say this makes seating a tubeless tire a lot easier due to the increased rate at which air can flow through the valve into the tire. But, that’s not all; the clever design means it’s almost impossible for the Fillmore valve to become blocked with tire sealant. Reserve say once you try one of these, you’ll never go back to Presta.
Reserve Fillmore Tubeless Valves
The common Presta Tubeless Valve is almost guaranteed to get clogged up with sealant over time, especially if your choice of tire sealant is any good. That’s because a lot of tire sealants these days are designed to seal holes that greatly exceed the width of the Presta Valve passage; Orange Seal claims ~6mm while Joe’s No Flats Podium Sealant claims up to 10mm.
The lack of a removable valve core means the inside of the stem has a much greater volume. But, it’s not the increased space that prevents clogging. That’s by virtue of the unique “pop it” design of the Reserve Fillmore Tubeless Valve, meaning it is actually sealed by a large O-Ring from the bottom. This is not the case for the standard Presta Valve, which is sealed via a much smaller O-Ring at the base of the valve core. On the Fillmore Valve, the airflow hole is much larger and thus better protected from sealant.
The only opportunity for the Fillmore valve to clog with sealant is if you go for the direct injection method, rather than filling the tire with sealant before popping the second bead onto the rim. With a regular Presta Valve, there’s an extra step which involves the removal of the valve core.
In the tech video, Garren from Reserve Wheels says regular Presta Valves “don’t let enough air in to seat a tire”. Well, that’s not strictly true. I’ve been able to seat many 27.5″ tires onto 30mm rims using the Presta Valve with the core still in pace. That said, it does become more bothersome the higher the tire volume gets, especially on 29″ wheels. I have often removed the valve core to increase the air flow rate, and even resorted to the use of an AirShot Tubeless Tire Inflator for really stubborn tubeless setups.
Either way, Reserve claim the Fillmore valve makes life much easier, regardless of the setup. And, it makes complete sense. The higher the rate of airflow, the easier it is to seat the bead onto the rim. A Reserve Fillmore Valve delivers 3X the rate of airflow of a Presta Valve.
Another nice feature of the Reserve Fillmore is the micro-adjust. As you loosen the valve cap, the mechanism allows the internal piece of the valve to rise with it; from there you can depress the valve cap to let out tiny amounts of air to soften your tire before dropping into a wet technical trail that demands as much grip as possible.
Reserve say the Fillmore Valve is compatible with all Presta head pumps, so it should also work with digital pressure gauges like the Topeak SmartGuage D2.
Some Limitations
The Reserve Fillmore valve is designed for mountain, gravel, and cyclocross rims between 18mm and 28mm deep. Due the lack of a removable valve core, Fillmore is incompatible with SRAM’s TireWiz – their onboard digital tire pressure gauge.
Pricing & Availability
The Reserve Fillmore Tubeless Valves retail at $49.99 USD for a pair and are available now from dealers worldwide.
