Funn MTB joins the rapid inflation race with a high-flow redesign of the presta valve, said to make tubeless tire inflation a quicker, easier affair. The $35 USD Funn FastAir Valve presents as a more affordable competitor to the Reserve Fillmore Valve, but is still slightly more expensive than 76 Projects’ Hi Flow No Clog offering. While the design is a sort of hybrid of the two, the concept is the same; the FastAir offers a higher volume path for airflow allowing for rapid tire inflation and, should also be less vulnerable to sealant blockages.
Funn FastAir Tubeless Valves
Much like the Reserve Fillmore, the new Funn FastAir Tubeless Valve claims to offer 3x the airflow of Presta. Similarly, the design seeks to solve a common drawback of the use of a Presta Valve. Tubeless tires often require rapid inflation in order to force the tire bead to seat on the rim effectively, and it is often the case that the tiny lumen of the Presta Valve simply isn’t up to the job.
Removal of the valve core allows for use of the full volume of the valve stem, increasing the rate of airflow. This normally gets the tire seated with a floor pump, rarely requiring use of an AirShot or compressor. The FastAir Valve offers up extra internal volume as is, without the removal of its core. Thus, the process of seating a tubeless tire with the FastAir versus Presta requires fewer steps, and should take up much less of your precious ride time.
A cross-sectional view of the valve internals reveals how the FastAir achieves that.
The traditional valve core is replaced with a hollow shaft through which air can pass. The base of that shaft empties out into the lumen of the valve stem. Here you’ll find the seal, beyond which is the lumen of the tire. Atop the shaft is the valve cap which, when screwed down tight, cinches the shaft up to seal off the valve. When the cap is unthreaded, the shaft can be pushed down to pop the seal, allowing air to flow freely in either direction.
We don’t have any numbers but, we assume the actual volume of the air flow path inside the FastAir to be much larger than that inside a Presta Valve, hence its ability to deliver 3x the airflow and thus, easier tubeless tire inflation.
Those familiar with the Reserve Fillmore and 76 Projects Hi Flow No Clog will appreciate how the Funn FastAir is, pretty much, a hybrid of the two. Funn seem to have combined certain features of each design to produce a new high-flow tubeless valve at a reasonable price point.
While the aforementioned claim to be significantly less susceptible to clogging up with sealant, Funn made no mention of that aspect in their marketing material. Likely, given the higher volume, it will be less susceptible to choking up. Actually, a brand representative has just confirmed to us that they are indeed claiming a “No Clog” bonus, and that you can inject sealant through the valve, negating the need to pop the bead when a top up is required.
Ultimately, whether or not this or any other tubeless valve does clog is largely dependent on the sealant you use. Some of them, like Joe’s No Flats Podium Sealant, claim to be able to seal holes up to 10mm in diameter.
Importantly, if it does clog, you can clean it out as it is completely rebuildable. Conversely, the more expensive Reserve Fillmore Valve, is not.
Importantly, the FastAir is compatible with tire inserts thanks to the slots on the base allowing air to exit sideways into the tire. And, it’s compatible with CO2 inflator heads, too. And finally, we are told it should work with a digital tire pressure gauge.
Pricing & Availability
The Funn FastAir Tubeless Valves will be available by the end of February, retailing at $35 USD per pair, and are sold with a one-year warranty. Get them in black only.