Reserve Fillmore Valves

Reserve's Fillmore valves enter a market saturated by both premium and cheap options – we've never had more choice. Unlike the majority of tubeless valves in circulation (no pun intended), the Reserves are not strictly Prestas, they're a Presta-compatible reimagining of a bike valve that prioritises high flow rate and prevents clogs. And they succeed. Wildly. It was surprising to be quite so excited by valves, but they're ingenious, and work brilliantly.

For the last five weeks, admittedly a brief service so far, they've been flawless. No leaks, no clogs, no mess, no loosening, and pressure has held. Installation was easy, and they've simplified tyre changes and sealant top-ups. They come in three different sizes to accommodate rim depths from 18mm up to 68mm, and, as Henry Ford put it, 'any colour so long as it's black' (though coloured anodised caps are now available). The only negative, really, is the price: at £34.50 they're a tenner more than 76 Projects', and £7.50 more than Muc-Off's.

Modern sealants are designed to seal holes about the same diameter as a Presta valve. Little wonder then that they clog with such alacrity. If you've yet to embrace tubeless, these could be the valves to change your mind.

> 9 things they don’t tell you about tubeless tyres

The Reserves went onto my 'everyday' gravel bike, which also serves as my 'as-needed' commuter, so they got a bit of high rotational speed from road riding, and some bouncing around on soggy bridleways.

Reserve claims three times the airflow over a regular Presta valve, which seemed believable in my back-to-back testing against the Tune tubeless valves they replaced. With a vigorous press on my track pump, it certainly felt like more air went in faster, and my GravelKings leapt enthusiastically onto the rim bead without extra coaxing or the pressurised tank on my Topeak Joe Blow Booster.

Topping up the sealant was similarly painless, with the gloop being pressed more easily though the wider valve. And, of course, there's no core to remove. Simply wipe the tip, add a little more air, then the cap and you're done.

Reserve says it uses the standard Presta interface so all pumps should work. They'll also work with tyre inserts like CushCores if you run those.

So far so good. But would they hold or would they leak? They held, perfectly. I attribute this to some very clever design. Reserve has removed the core and maintained a wide stem for high volume through-put. Additionally, it's moved the sealing mechanism (a poppet) to the bottom of the valve on the inside of the rim. The poppet (an O-ring on the tapered head of a steel rod) is held closed both by the positive pressure inside the tyre pushing it shut, but also by the valve cap. The cap screws down onto the valve stem AND onto the other end of the steel rod that runs the length of the valve. Screwing down the cap therefore also pulls the poppet up and shut. You can see the separate threading on the rod.

Effectively, the poppet is both pushed shut by the air pressure in the tyre, and pulled shut by the valve cap. This is more secure than a Presta valve, and results in a tight closure with no discernible leakage. Hats off to this engineering.

The Presta valve, though ubiquitous, has remained largely unchanged in the last century, and the Reserves demonstrate how poorly suited Prestas are to the demands of tubeless and sealants. The Reserves are that rare combination of 'better' and 'simpler'; without a core to remove, they're less fiddly, less messy and way more durable. In fact, it was only when trying these that I realised how I had just accepted bent brass Presta valves as a matter of course, particularly long-stemmed valves.

When it comes to adjusting the pressure, unscrewing the cap a turn or two allows you to press down on it to 'micro-adjust' the pressure, letting out small, controlled blasts. Not vastly different from a Presta, but the process feels very much more intentional.

The other striking quality about the valve is, well, its quality. It's a surprisingly tactile thing; it screams premium, and the finishing is exemplary. The machined threading feels very fine, and both the cap and locknut spin effortlessly and rapidly. I've never ridden a set of Reserve wheels, but the engineering of these valves makes me want to.

It's been very cold and very wet recently, but the Reserves have behaved and performed flawlessly. It's really that simple. And they've won near universal praise from anyone who's tried them.

Value and conclusion

The only (again a near-universal) detraction is the issue of their price and value. Even in a world of four and five figure bikes, £35-£45 (depending on size) for a pair of valves is not nothing, especially when reasonable valves can be had for a quarter of the price, nice valves for half the price, and next-best offerings for two-thirds of the price.

Stu really liked the Muc-Off Tubeless Presta valves he tested in 2019 when they were £22.50, although the 'all new' V2s are £27, and Chad thought the 76 Projects Hi Flow No Clog Tubeless Valves were excellent, and they're cheaper at £24.50 a pair. I haven't tried those, but going by Chad's review I'd say the Fillmores are a lot simpler to fit, simpler to 'close', don't have any kind of core to clog, are a wider design so will (likely) allow more/faster air through-put, and seemingly have better Presta/pump compatibility.

The design of the Fillmores is really stand-out for its novelty and simplicity, and they're still going strong.

In the long-term, despite the high cost of purchase, with a lifetime guarantee backing these up, the point at which they pay for themselves becomes a matter of when, not if. They're expensive for valves to be sure, but I'd say they're the best valves you can buy.

Verdict

Novel design and technical ingenuity at its best – these valves are undeniably expensive but commensurately brilliant