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Black Diamond Camalot Z4 Review

Our favorite small cams are a breeze to place and effectively incorporate innovative technology
Top Pick Award
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Price:  $70 List
Pros:  Wide range per unit, light, rigid when placing but flexible when placed, narrow head width, thumb loop, smallest unit currently made
Cons:  Not the most affordable, smaller units lack double axle and aren’t as smooth, trigger wires can’t be replaced at home
Manufacturer:   Black Diamond Equipment
By Andy Wellman ⋅ Senior Review Editor  ⋅  Jun 15, 2020
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81
OVERALL
SCORE


RANKED
#2 of 9
  • Free Climbing - 20% 9
  • Weight - 15% 7
  • Range - 15% 7
  • Horizontal Cracks - 15% 9
  • Tight Placements - 15% 9
  • Durability - 10% 7
  • Walking - 5% 7
  • Aid Climbing - 5% 8

Our Verdict

The much anticipated Black Diamond Camalot Z4 were released in the spring of 2020 with quite a lot of hype, and don't disappoint. We think they are the best small camming units you can buy, for which they garner a Top Pick Award. In particular, we love the smooth trigger pull, narrow head width, and wide range per unit, making them easy to fire into cracks of all shapes and sizes, on all types of rock. They range from a green .75 size down to the green 0 size, currently the smallest camming unit available on the market, and also come in offset sizes. While it's advantageous to carry multiple different types of small cams on your rack, a set of the Z4s promises to serve you well, and will likely be the first set you choose to accompany you on any climbing adventure.

Compare to Similar Products

Our Analysis and Test Results

The Z4's replace the X4s in BD's lineup, which have been discontinued, and also overlap with the size range of the old C3s, which were discontinued a while ago. They are currently the only micro cams that BD makes. They range from #0 up to .75, with the .3-.75 overlapping with standard Camalot C4s and .4-.75 overlapping with Camalot Ultralights, so prospective buyers will need to decide which types of units they want in these sizes. They use the same color scheme as other BD cams, but the sewn Dynex sling comes in a checkered pattern (white/cam color) so that they can be easily differentiated on the harness. They also come in offset sizes with bicolor slings for identification.

The most notable feature on these cams is the new RigidFlex stem, which uses two twisted cables as a stem in the larger sizes, and claims to be flexible when placed, but rigid when the trigger bar is pulled, thereby aiding in placement and removal. This feature does work, although it is a lot more effective in the smaller sizes than the larger ones, where the weight of the head works as an effective lever to induce some stem floppiness. This feature directly addresses one of the principal complaints against the X4 — that they were too floppy — and in this regard is an improvement. Other complaints against the X4 were that the stems were easily kinked, they were too heavy, and the heads were too wide. With the Z4's dual twisted wire stem, it should be much harder to kink the stem, and these units are also considerably lighter and have narrower heads — in line with the old C3 head width. While there is no perfect micro cam, these units are a vast improvement over their predecessors and have quickly become our favorite small cams.

Performance Comparison


The Z4s include new technology including the RigidFlex stem  and use the same BD color coding  thumb loop  and easy trigger pull that make them a favorite choice for free climbing.
The Z4s include new technology including the RigidFlex stem, and use the same BD color coding, thumb loop, and easy trigger pull that make them a favorite choice for free climbing.

Free Climbing


When free climbing, you want to be able to quickly identify the cam you need, remove it from your harness and place it properly and effectively — and you may need to do this very quickly! The Z4 help accomplish all of these tasks and are a fantastic choice for free climbing on all types of stone. They use familiar BD color schemes, the most common and well known, especially in the larger sizes, so there is no need to memorize a new scheme, or perform a translation in your mind. They also use a double-axle design down to the .3 size, which allows for a wider range per cam. If you slightly misjudge the size of the crack, chances are that you can still place a Z4 that will hold a fall, whereas this might not be the case with a cam that has a smaller range, forcing an under-cammed placement. The convenient thumb loop makes it easy to quickly grab the cam and pull the trigger, with no adjustment needed.


The new RigidFlex stem design also aids in these cam's efficacy while free climbing. A rigid stem is preferable when placing and removing cams, because it transfers the movement of your hand into the camming head, making it easy to wiggle in or out. Conversely, a flexible stem is preferable for a placed cam, as it reduces walking and also the likelihood that the cam will become damaged if weighted over edges. The RigidFlex design makes the stem less wiggly when the trigger is pulled, although it doesn't become completely stiff, and this seems to work better on the smaller units than the larger ones, which we are thankful for since smaller cams often need a lot more fiddling to get in and out of thin cracks. When the trigger is released, the stem becomes flexible, and so both desires are accomplished with the same design.

Removing a Z4 cam at the top of the classic pitch Orange Peel in the Cracked Canyon at Ophir. By pulling the trigger like this the stem becomes more rigid  which makes it easier to slide out of the crack  especially in a funky placement where it needs to be wiggled around a bit.
Removing a Z4 cam at the top of the classic pitch Orange Peel in the Cracked Canyon at Ophir. By pulling the trigger like this the stem becomes more rigid, which makes it easier to slide out of the crack, especially in a funky placement where it needs to be wiggled around a bit.

Weight


On our independent scale, a purple .5 size weighed in at 2.8 ounces, which was a tad heavier than the 2.71 ounces listed on BD's website. An entire set of these seven cams would end up weighing 14.82 ounces, according to BD's weights, or slightly less than a pound.


This is pretty light, especially considering how many wires are used to make up the stem, that it's a four cam unit, and that many of the units have double axles in the heads. It weighs about 0.4 ounces less than the old X4, so weight has been cut. That said, most of the "Alien" style designs, which have single axle heads, single wire stems, and a woven trigger sheath, are a fair bit lighter.

At 2.8 ounces for a 1 inch piece  this unit is lighter than predecessors in the BD lineup  but is not in competition for the lightest finger sized piece you can buy.
At 2.8 ounces for a 1 inch piece, this unit is lighter than predecessors in the BD lineup, but is not in competition for the lightest finger sized piece you can buy.

Range


The full range of Z4s includes seven different cams that go from the smallest currently made (7.5 mm, .29 in.) up to the green .75 size (42.1 mm, 1.66 in.). For small cams, this is a very wide range, and the flexible stem design is not practical for any larger head size. Most notably, the green 0, with a 7.5mm bottom range, is now smaller than the smallest C3, and adds a fair bit of range on the bottom end below the .1, which used to be the smallest size.


Even more pertinent, however, is the individual cam range, which means how much space a single unit can fill in a crack. A wider range means you can far more easily shove a slightly mis-sized unit into a placement. The individual size range for Z4s is as good as all Camalots, and far better than any of the single axle competitors, which greatly adds to both their ease of placing, as well as their versatility.

The double axle design allows for a greater range of placement per unit  which means that when you grab a grey .4 and shove it into a changing and constricting crack like this one  it is more likely to sit within the ideal range  a very handy feature for free climbing near your limit.
The double axle design allows for a greater range of placement per unit, which means that when you grab a grey .4 and shove it into a changing and constricting crack like this one, it is more likely to sit within the ideal range, a very handy feature for free climbing near your limit.

Horizontal Cracks


The flexible wire stem means that it can bend over edges and makes it a great candidate for horizontal cracks. Furthermore, the double-twisting cable design in the .3 and above sized units means that if weighted over an edge, the two cables can actually shift somewhat dynamically in relation to each other, lessening the chance of a catastrophic kink in the cable that would necessitate retirement. These stems also bend equally well in all directions, so it's not only pure horizontals where the flexibility proves to be an advantage.


The plastic sheath that encases the stem and the four trigger wires is cut in a slinky-like pattern so that it can accordion itself to bend in any direction. While it seems this sheath may be a durability concern, we have yet to hear of, or experience, any issues.

They have a flexible stem  which allows them to bend over edges like this one at Smith Rock  without deforming. Extending such a placement with a sling can also help direct potential fall forces downward without loading the stem over the edge.
They have a flexible stem, which allows them to bend over edges like this one at Smith Rock, without deforming. Extending such a placement with a sling can also help direct potential fall forces downward without loading the stem over the edge.

Tight Placements


Placing cams into tight, shallow cracks requires a narrow head that won't bottom out before all four cam lobes have the opportunity to make contact with the rock. One of the biggest improvements made with the Z4 is the narrowing of the head, as they are narrower than old X4s, comparable to C3s that only have three lobes, and even narrower than competing "Alien" style designs like the Dragonflys, which should have the advantage of cam springs recessed inside the lobes. In short, these are narrow-headed cams that fit well in shallow cracks.


The Z4s on the right compared to the X4s  which they replace  and are no longer in production. Besides the obvious differences in trigger sheath design  this photo is meant to show how much narrower the heads of the newer cams are  which helps in tight placements.
The Z4s on the right compared to the X4s, which they replace, and are no longer in production. Besides the obvious differences in trigger sheath design, this photo is meant to show how much narrower the heads of the newer cams are, which helps in tight placements.

The Z4 cams on the bottom with the Dragonflies on top for size comparison. In the two larger sizes shown  the purple and grey  the cams are roughly the same width  whereas the two smaller sizes  blue and yellow  the Z4s actually have a narrower head. Despite the color coordination  the BD have larger range per unit  and so the two brands do not match up exactly for ideal placements.
The Z4 cams on the bottom with the Dragonflies on top for size comparison. In the two larger sizes shown, the purple and grey, the cams are roughly the same width, whereas the two smaller sizes, blue and yellow, the Z4s actually have a narrower head. Despite the color coordination, the BD have larger range per unit, and so the two brands do not match up exactly for ideal placements.

Durability


We tested these cams extensively for three months immediately after they were released, and had no issue with their durability during that short time. Our only complaint is that on our yellow .2 sized unit, which has a single axle rather than the double axle in the larger units, it was possible for the cams to become aligned crookedly. Also, Black Diamond is not selling trigger repair kits, and is also not authorizing third party repairs, and so if you experience a blown trigger wire, you must send the unit back to them for repair, for a fee.

A close up of the flexible trigger wire mechanism. Four independent trigger wires parallel the stem on the inside of this black plastic sheath that is cut like a slinky so it can accordian back and forth as the cam bends. It works great  but we suspect that this will be a potential durability concern over time  although our testing has not yet produced any problems.
A close up of the flexible trigger wire mechanism. Four independent trigger wires parallel the stem on the inside of this black plastic sheath that is cut like a slinky so it can accordian back and forth as the cam bends. It works great, but we suspect that this will be a potential durability concern over time, although our testing has not yet produced any problems.

Our gut tells us that there may end up being some issues with the plastic, slinky-like trigger sheath tearing, although we searched reviews and forums for hours and found no reports of durability concerns — yet. Climbing gear is put under incredible strain, and as of publication, there simply has not been enough time and use in the community in general for us to comment on what true durability concerns, or advantages, there are.

The lobes are made out of a harder aluminum alloy than many other small cams  so they should see less deformation with repeated use  and are both sandblasted and not annodized in order to improve the grip against smoother rocks.
The lobes are made out of a harder aluminum alloy than many other small cams, so they should see less deformation with repeated use, and are both sandblasted and not annodized in order to improve the grip against smoother rocks.

Walking


Walking is when the interaction between the cam sling and the rope once the climber is above the unit causes the head to move positions, often deeper into the crack. These cams have relatively short slings (3.75"), making it more likely that the rope may pull on the unit if you don't extend them with a quickdraw or extendable runner.


The flexible stem helps to cut down on the walking action, as the movement of the sling from the rope can be mitigated by the stem flexing. However, placed poorly or not extended properly, these cams can walk just like other Camalots do.

This is a great example of where a cam that walks could get pushed deeper into the crack to where it would become very difficult  or impossible  to get out. The flexible stem  shown to great effect here  allows the rope to pull in various directions on the cam without it necessarily walking deeper into the crack.
This is a great example of where a cam that walks could get pushed deeper into the crack to where it would become very difficult, or impossible, to get out. The flexible stem, shown to great effect here, allows the rope to pull in various directions on the cam without it necessarily walking deeper into the crack.

Aid Climbing


Due to the shutdown of national parks during the Covid-19 crisis, specifically Yosemite, we were not able to test these cams while aid climbing before publishing this review. Check back later for our opinions and experiences as we manage to use them for this use.

John Schaefer not aid climbing as he seconds a pitch on the 8-pitch Savelli Express in Ophir while testing Z4 cams. Aid climbing can take you to the tops of giant big walls  and while we think these cams will work relatively well for this purpose  especially in the offset sizes  we don't see them becoming cult classics like totems or aliens.
John Schaefer not aid climbing as he seconds a pitch on the 8-pitch Savelli Express in Ophir while testing Z4 cams. Aid climbing can take you to the tops of giant big walls, and while we think these cams will work relatively well for this purpose, especially in the offset sizes, we don't see them becoming cult classics like totems or aliens.

In general, narrow cam heads, flexible stems, very small sizes, and offset units are all great advantages when aid climbing, and the Z4s have all of these attributes, so we expect them to function pretty well, at least on mellower clean aid routes. They lack two features that are a boon while aid climbing: the ability to independently manipulate individual lobes, a large reason why Totem Cams are the top choice for aid climbers, and round shaped lobes, common among the "Alien" style designs, that often fit into blown out pin scars a bit better.

Value


These units retail for the same price, regardless of which size you choose, and are only a few dollars more expensive than comparably sized Camalot C4s, but are significantly less expensive than Camalot Ultralights. We think they present great value, considering they are our favorite small cam, but if you are shopping purely based on budget, you can find better deals on cams that are still really high quality and perform well; check out our Best Buys.

Testing cams on some of the awesome parallel sided cracks of the Lower Gorge at Smith Rock  Alon Dahari reaches for the Z4s  the perfect tool for this finger sized splitter.
Testing cams on some of the awesome parallel sided cracks of the Lower Gorge at Smith Rock, Alon Dahari reaches for the Z4s, the perfect tool for this finger sized splitter.

Conclusion


Black Diamond Z4s present an upgrade over previous versions by unleashing new and innovative technology while also addressing the concerns raised by both athletes and consumers. These are some high tech gadgets that are simple and easy to use, and are easily among the most versatile small camming units you can buy. We think both new and experienced climbers alike will appreciate having them on their rack, and will benefit from their many advantages over other small cam designs.

Following an awesome trad corner in Ophir  what crack climbing dreams are made of.
Following an awesome trad corner in Ophir, what crack climbing dreams are made of.

Andy Wellman