Jim Langley recently wrote a pair of articles on new valve technology, sparking comments from many RBR readers. (Part 1 and Part 2). Unbeknownst to Jim, I was concurrently in Chicago putting the Muc-Off Big Bore Hybrid Tubeless Valves and their new Gravel & Road Sealant to the test.
Muc-Off Big Bore Hybrid Tubeless Valves
Muc-Off Big Bore Lite Tubeless Valves
Price: $50/pair (currently on sale $37.50)
Sizes: Small – 30 mm, Medium – 35 mm, Large – 45 mm, and X-Large – 60 mm
Colors: Black, Iridescent, Red, Blue, Orange, and Pink
Availability: Online and retail
How obtained: Company samples
RBR advertiser: No
Jim Langley recently wrote a pair of articles on new valve technology, sparking comments from many RBR readers. (Part 1 and Part 2). Unbeknownst to Jim, I was concurrently in Chicago putting the Muc-Off Big Bore Hybrid Tubeless Valves and their new Gravel & Road Sealant to the test.
Swapping out a perfectly good tire with fresh sealant wasn’t feasible, so I opted to install the valves on a fat tire bike whose tire had seen better days. The packaging includes a QR code linking to Muc-Off’s instructional video. The step-by-step guide further affirmed just how simple the installation process was.
Unboxing the Big Bore Hybrid Tubeless Valves
Included in the box are:
- Two Big Bore valves
- 4mm machined hex key slot for installation and removal
- Various rubber bases to optimize fit and seal with multiple rim types
- Bespoke Spanner designed to tighten the Big Bore body during installation and removal
- Flexible tubing for spill-free filling tires with sealant
Quality Built and Easy to Use
Like so many of the Muc-Off products I’ve tested, the quality of these valves is top-notch. It is crafted from 7075 aircraft-grade CNC machined aluminum construction with a stainless steel ball valve. The company designed the valves to deliver maximum inflation with high airflow, using a “straight through” internal design. With the integrated ball valve system, the valve ensures fast airflow for tire inflation and sealant filling.
I run tubeless on my fattie, MTB, and gravel bikes. One common problem is that the valve gets clogged with sealant, requiring the removal of the valve core to “degunk.” Sometimes, the Presta valve is so gunked up that it must be replaced. I bought a couple of dozen valve cores to have on hand for just such a problem.
In addition to issues with the valve core, sealant can clog the valve stem, causing problems when inflating the tire. Muc-Off’s new design allows for higher airflow than traditional Presta valves. The company states it is 254% higher due to the straight-through bore design.
Muc-Off has also redesigned the valve using a ball valve and integrated lever. A lever on the side of the stem allows the valve to be quickly opened or closed. When pumping up a tire, you close the valve before removing the pump head. Thus, air is not lost when the pump head is removed.
Compatibility Issues
Most modern pumps use “smart head” technology, which automatically adapts to whichever valve you use ― Presta or Schrader. But if you have a pump (floor, handheld, or mini) or tire pressure gauge that only works on Presta valves, it probably won’t work with the Big Bore Hybrid.
Big Bore Hybrid comes with the same Presta style valve stem as the Lite version but with a wider Schrader valve head offering a 5.7mm internal diameter and its Presta rim hole compatible. Even a gas station car pump can be used without an adapter.
The design of the Big Bore Lite is for Presta rim hole and inflation compatibility, with a 3.3mm internal diameter valve head. No matter which stem length you choose, It offers up to 230% greater airflow than a standard Presta valve.
When ordering the Big Bore, get the correct stem length. If it is too short, you won’t be able to turn the ball valve. The Big Bore is available in four lengths (small – 30 mm, medium – 35 mm, large – 45 mm, and XL – 60 mm) and several colors to match or contrast your rims or frame (pink, black, iridescent, red, blue and orange).
New Road and Gravel Sealant
After installing the Big Bore valve, I added Muc-Off’s new Road & Gravel sealant. The flexible tubing supplied with the valve made it easy and clean. The sealant is formulated from advanced synthetic latex and biodegradable sealing particles. The company states it will seal holes up to 7mm. It’s been a month since the valve and sealant were installed, and there have been no leaks or flats.
The specs state the sealant won’t freeze down to -15°C, so this winter will be a good test when I take the fattie out for a spin.
Bottom Line
Does size really matter? When inflating large fat, MTB, or gravel tires, it does. Having the ability to have 254% higher airflow makes it quicker and easier to inflate a tire. In addition, not having to deal with sealant gunking up valve cores or stems is a game changer.
Sheri Rosenbaum regularly contributes articles and reviews products for RBR. She’s an avid recreational roadie who lives in the Chicago area and a major advocate for women’s cycling, serving on the board of directors and volunteering with the Dare2tri Paratriathlon Club. Click to read Sheri’s full bio or visit her web site sunflowersandpedals.com.
Creative product. Interested in their weight since a relatively long one is needed based on the design. My experience with long stems is that sometimes the extra weight causes the wheel to shudder at high speeds. In that case I use golf club weights to balance the wheel (same concept for balancing a car wheel).
DK,
The weight will vary depending on length and hybrid vs lite.. My suggestion is to determine which valve you need and use the Contact Us link on the Muc-Off site. The valves I tested are installed so can’t weigh them.
Sheri,
Any idea if Muc-Off has changed the composition of its sealant? I haven’t used it, and given reports I hear from others, haven’t been remotely tempted to switch from Orange Seal Endurance.
So tough to test with any precision. Maybe intentionally puncturing a tire with different-sized nails and then spinning the tire would be representative?
The best sealant I’ve found is SILCA Ultimate. really does stop leaks with very little loss of sealant. it’s a foaming latex formula combined with chopped carbon fibers to boost sealing power even at higher pressures. Check it out.