The Zefal Z Bar Plug set is a well-priced and good-quality in-handlebar tubeless repair kit. However, the plugs themselves are a bit of a letdown and things can get a little rattly in the rough stuff.
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Zefal Z Plugs - Technical details
The Z Bar Plugs by Zefal is the brand's one-stop tubeless repair solution designed to cleverly store in the empty space in your handlebar void. The kit includes two nylon composite canisters that hold the tools themselves and a nice pair of laser-etched CNC aluminium end caps that they screw onto. These end caps are held in place via a neat expanding wedge system. It involves simply screwing the cap clockwise to secure them in place in the bars, and anticlockwise to access the tools - simple.
The wedges themselves are held together by a pair of thin o-rings that can come loose if the end cap is unscrewed too far - more on that later. The Z Plugs system is nicely versatile, fitting bars with inner diameters ranging from 17 to 21mm and Zefal claims they work with both mtb and drop handlebars.
The Z Plugs are a two-part system, one bar end houses the main plugging tool which is a fairly generic fork design, although this one has a nice file section on the shaft that works as a reamer to ensure a clean edge for the plug. Another clever touch is a Presta valve core removal tool at the end of the handle and a slot to store a spare master link.
The other bar end contains a second canister that holds a stubby little knife for trimming plugs and there's room to store several additional tubeless plugs - Zefal includes 3 x 2mm and 3 x 4mm plugs in the kit.
The whole package is very neat and tidy and weighs in at a very respectable 75g with plugs on my digital scales.
Zefal Z Plugs - Performance
First off, if like me you usually run single clamp lock-on grips with a built-in end cap such as my ODI Elite Pro’s, you’re out of luck as this kind of in-bar tool storage requires an open-ended grip design to work. During testing, I switched out my usual paw pleasers for a spare set of Revgrips as the dual collar system integrates perfectly with the Z Plugs.
Initial installation was a doddle, it's simply a matter of screwing the endcaps into the tool carrier cartridges and slotting the whole assembly into the handlebar, then turning the end cap clockwise until it's nice and snug. The smart-looking CNC'd end caps are nice and low profile and have a tactile scalloped edge to provide a bit of purchase for quick fitting and removal even with mucky or sweaty hands.
Once screwed in, they don’t budge. The expanding wedge works a treat in keeping them in place even after a few minor offs and a bit of tree clippage. Obviously, in the event of a big crash, there's a chance of one going flying, but in general, they are super secure.
My first few rides with the Z Plugs installed were quick jaunts down the local woods where they remained wholly inconspicuous. However, during a big day on the moors, I noticed a persistent rattle on a long fast descent that I initially put down to a wobbly brake lever. However, on closer inspection it seems that because the tool cartridge section is considerably slimmer than my handlebar's internal diameter and the unit is reasonably long, even a small amount of movement at the bar end is magnified at the innermost end allowing it to vibrate against the inside of the bar over rocky terrain.
I actually bodged a bit of a fix by administering a couple of wraps of self-amalgamating tape to the noisy end to absorb the vibration. This pretty much eliminated the problem, but it’s a shame Zefal couldn’t have built in some kind of dampener at the design stage. I also discovered I had to be very careful not to dislodge the thin rubber O-rings that secure the expanding wedge when the tool was removed from the bike as it would be very easy to lose one during a trailside fix.
Onto the tools themselves and Zefal has done a great job. The plugging fork is a nice design with a good-sized handle for solid purchase and the knurled reaming section built into the shaft works brilliantly. The forkhead is easy to thread too thanks to a slightly wider ‘eye’ than most. It's just a shame the included tubeless plugs I received were such poor quality - dry, stiff, and in no way sticky. They were more like bits of old shoelaces or small twigs than tyre plugs. Perhaps I was unlucky and received a dodgy batch, but as it stands, be prepared to substitute them for some aftermarket ones.
The inclusion of a Presta valve core tool and master link storage slot in the handle is a nice touch and a useful addition. The other bar end houses spare plugs and a little knife for plug trimming duties and it's not bad, although the handle is very small for my big clumsy hands and a longer and sharper blade would make the job much easier. Additionally, for those of you riding in bear country, the knife is easily accessible should you need to fight one. (This is a joke - please don’t attempt to take down a grizzly with this, it won’t end well).
Zefal Z Plugs - Verdict
On the whole, I was impressed. Zefal has produced a discreet and effective tubeless repair system that stores conveniently in the wasted space inside your bars and is quick to hand in the event of a puncture. Build quality is good, although I’d like to see a more reliable method for retaining the expanding wedge than the thin and easily dislodged O-ring solution in play at present. I've had zero problems with durability - the Z Plugs have taken plenty of knocks, and besides a couple of scratches to the anodised alloy end cap - mainly from resting the bike up against walls) they are proving to be plenty tough enough for MTB use.
At just £30, the Zefal Z Plugs offer excellent value and functionality for the money - although you may need to budget for some decent tyre plugs to replace the duff ones included. Alternative options from rival brands include the excellent Muc-Off Stealth Tubeless Puncture Plug kit - but at £40 it's significantly more expensive than the Z plugs kit and essentially does the same job. The Muc Off system’s all-aluminium build and expanding silicone retention system may prove more durable over time and they are available in a choice of 12 blingy anodised colours for the matchy-matchy look if that's your bag. However, a major gripe for me is that once installed on the bike, a 4mm Allen key is required to actually access the tools - not ideal when you're battling a puncture in a race scenario where every second counts.
Another similarly priced contender is the Lezyne Tubeless Insert Kit at £28. However, it is a single-sided affair and subsequently, there’s no room for a trimming blade. The CNC’d alloy construction should prove durable, but it relies purely on O-rings to provide a friction fit in the bars, which is far less secure than the screw-in wedge design of the Zefal system.
To sum up, if you are ok with running open-ended grips, which is actually a rarity these days - I’d happily recommend the Zefal Z Plugs. They offer a comprehensive tubeless repair solution in a neat and discreet package. Sure there are a couple of minor niggles, but these can be easily remedied, and for the price, can be overlooked.