Marzocchi Bomber Z1 Coil (2020-2024) Fork

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Afew years ago, Marzocchi resurrected the Z1 to much anticipation. While damper technology has moved on from the open-bath systems of old, there was disappointment in some circles that the coils of the original fork were passed up in favor of a standard FOX air spring – Marzocchi's parent company. While air-sprung forks have come a long way in terms of sensitivity and a reduction in running friction, there's no shortage of riders who swear by (or at least reminisce about) the uber-sensitive plushness of a coil. Early Marzocchi coil forks from the original Z1 Bomber to the Shiver and the 888 are the stuff of message board and comment section legend, with tales of buttery-smooth travel combined with simple adjustments, generous service intervals, and a rugged, bombproof chassis at a reasonable price. Feeling nostalgic? Have a look at the new 2020 Marzocchi Z1 Coil.

Z1 Coil Highlights

• 36mm chassis
• 27.5 and 29-inch versions
• Adjustable travel: 160-170-180mm (27.5) / 150-160-170mm (29)
• Offset: 37mm (27.5 only), 44mm (27.5/29), 51mm (29 only)
• Lightweight silicon-chromium steel spring
• Air assist for progressivity and bottom-out control
• 8mm adjustable preload in 0.5mm increments
• Four spring rates at 7.5 lb/in increments
• Noise management system
• Grip Sweep damper
• 15 x 110mm Boost axle
• Starting weight: 2,525g (5.56-pounds, claimed)
• Coil conversion kit only: 298g
• Colors: Matte black or gloss red
• MSRP Z1 Coil fork: $749 USD
• Availability: January 2020

Coil conversion kits are also available for Z1 air and FOX 36 Rhythm series forks. These include a $45 coil spring and $130 plunger kit. Note that you cannot go back to an air spring after making the switch.

Initial Impressions

To blend in, our 29-inch test fork arrived in identical dress to the current Z1 air fork that debuted in 2018, right down to the air pressure chart on the left leg. Hiding in plain sight on several group rides, the only indication that something might be different is the laser-etched preload adjuster on the left leg. The iconic 'M' shaping of the lower arch remains unchanged, and other than minor graphic difference there is little to distinguish the new Z1 coil from its sibling Z1 air we previously reviewed. We were big fans of the original Z1, so it was with much anticipation we dove into the new coil version.

Our test fork came with two spring options for our 160-pound test rider, a medium 40 lb/in and firm 47.5 lb/in. Swapping between them was as simple as unthreading the spring cap, pulling out the old spring and plastic retainer and dropping in a new spring. It's highly recommended that you use a chamferless socket, Knipex pliers, or something similar for this job as the soft wrench flats are of minimal height and its quite easy to round off the edges if you aren't careful.

Travel adjustment, while relatively simple, is a bit more involved. By swapping one or both of the 10mm plastic spring spacers (red) from the top of the spring to the underside of the bottom-out assembly, the travel can be reduced in equal-sized increments. Doing this, however, requires dropping the lower legs and pulling the spring plunger assembly out of the stanchion. If you've ever done a full lower leg and air spring service on a current fork it is essentially the same task. When in doubt, it's best to leave this step to your local shop or suspension tuner. With the fork off the bike we were able to work carefully enough to complete the travel adjustment without losing any lower leg oil, but just in case it's best to be prepared with the correct suspension fluid in case you need to reset the levels. Most people will simply set-and-forget their preferred travel or purchase the fork pre-configured at that number, so it's hard to consider the extra effort a significant drawback.

Aside from the coil spring assembly the other features are identical to other Z1 and select FOX 36 forks, the highlight of which is surely the simple yet incredibly capable Grip Sweep damper. While using an off-the-shelf damper might sound like a corner-cutting move, we don't see it that way. Besides being an excellent, proven system the FOX Grip damper is easy to service, has proven reliability, and it aides in keeping the overall cost of the fork down. All wise decisions.

The new Marzocchi Z1 Coil is an excellent fork, full stop. It may not have all the features of a premium or more expensive race-level fork, but it is not lacking in performance.

With the fork installed all we had to do was install the front wheel, fiddle with the quick release, fiddle with it some more and we were good to go. While it may seem unfair to pick on something as basic as a front axle, we've been spoiled with the designs of other brands that simply spin into the same place, level and all, every time. We never did figure out a method where we didn't have to use a series of ratchet-like turns at the end to get the lever to point up in a visually pleasing way. Some riders may wish to ditch it for a bolt-on option.

On The Trail

If you've come here to read raves about the Z1 Coil's small-bumps sensitivity, trail leveling plushness, and bomb hole swallowing then you won't be disappointed. Well, there is a slight chance you might be which we'll get to in a second, but first the highlights. The fork is exceptionally sensitive, and run back-to-back with a freshly serviced, more expensive RockShox Lyrik Ultimate we would have to give the Z1 a slight edge in this department for sure.

It is possible for a fork to be too sensitive and soft off-the-top and Marzocchi was wise to include an indexed preload dial that provides 8mm of adjustment in .5mm increments. It's quite effective for tuning both the initial feel of the spring and the sag point, however turning it more than halfway (7-8 clicks from open) begins to negatively affect small-bump performance. The full range of adjustment is shown in these images:

On the damper side, the Grip Sweep was equally impressive both with its simple adjustment and arguably above-price-point performance. Turning the unindexed gold dial adds a degree of both high and low-speed compression damping simultaneously and it didn't take more than a run or two down our local hill to find the sweet spot. On the rebound side we ended up on the heavier side (more rebound damping) of the recommended range, but still within Marzocchi's recommended settings. The Grip Sweep may not have the multi-function independent adjustability of the more advanced Grip 2 damper found on higher-end FOX forks, but it also suggests that sometimes if you don't have the option of more dials to turn you don't miss them.

Our test rider found running the damper wide-open to be a bit too erratic for his liking and felt the sweet spot of support and sensitivity was anywhere from 1/8 to 1/3 of the total range starting from fully open. Anything much past halfway in felt overly harsh at all but the highest of speeds, although this range may be appropriate for heavier riders.

If you read "air assist bottom-out control" in the feature list and expected something similar to some of the adjustable aftermarket coil-air hybrid options out there, you won't find anything of the like on the Z1 Coil. Keeping with the themes of simple performance and reasonable price, Marzocchi has opted to utilize the trapped air in the lower leg as a rudimentary air spring. It's only at atmospheric pressure, but by sealing the bottom of the spring assembly the volume of air is small enough and gets compressed far enough to help resist bottoming out. Marzocchi isn't the first to do this – Ohlins also uses natural air in the system in a similar way – but they've done it quite effectively. It's most pronounced at the end of the stroke and does an excellent job keeping the fork from feeling like it has bottomed out (which is good, because the stock bumpers are not very soft). You can see its impact on the fork near bottom out in this video with the coil spring removed:

While we wouldn't go so far as say the transition from the linear coil to the air assist was abrupt, it didn't have the same smoothly building progression that can be achieved with the best air fork. That might also have been due to the only real challenge we had with the fork. One that was not insignificant.

Things That Could Be Improved

A potential downside to a coil-sprung fork is always going to be the spring. Namely, the available spring rates and whether or not you can find the right one. At 160-pounds kitted up, our tester found the 40 lb/in medium spring (150-180lb rider) too soft for aggressive riding or laps at the bike park. Bumping up to the 47.5 lb/in firm spring (180-210 lb rider) made the front end far too stiff even with damper and preload run wide open. With the firm spring not being a viable option, we did our best to make do with the softer setup. This meant adding 7-8 clicks of preload to reduce sag and increasing compression damping to help the fork sit up a bit over successive hits and resist diving. Using the available adjustments allowed the fork to be tuned considerably and resulted in a much more controlled ride, but it was still a compromise any time the pace was pushed. At some point, the addition of extra preload and/or compression damping begins to negate the most positive traits of a coil spring, namely their small bump sensitivity (traction) and linear nature (comfort and control), and we felt riding the medium spring as aggressively as we would have liked required too many compromises.

The most important factor in suspension tuning is setting the correct spring rate, and we'd love to see the Z1 have more options.

We're well aware that what our test rider may want in a $749 fork is not necessarily what the majority of riders would like, and it's entirely possible (likely in fact) that someone of the same weight would have found the 40 lb/in spring to be spot on, that is the challenge with using coils versus air. When all you want to do is add that extra 2-5psi, it's just not an option. Preload increases to force needed to get the spring to compress initially but it does not affect the rate.

We're dwelling on this point in hopes that Marzocchi takes note because the Z1 Coil is overall an outstanding fork. But it may be let down by the choice to offer only four coil options at 7.5 lb/in steps. Other brands, including Ohlins, PUSH, and Vorsprung, opt for 5 lb/in steps to better find the sweet spot across a wide range of fork travel, terrain, rider weights, styles, and preferences. The most important factor in suspension tuning is setting the correct spring rate, and we'd love to see the Z1 have more options.

Other than the spring range our improvement wish list is fairly small. Yes, the fork is heavy, but only about a half-pound more than the air version. Rather than making the Z1 Coil lighter and pricier, it would be great to see coil options on FOX's higher-end forks as well – something they've hinted may be coming in the future.

We do wish the compression dial was indexed. If you're like us and throw the switch full closed on long smooth climbs it's nice to set it back to exactly the same spot every time. Also, while it never moved on us while riding, the dial's ease of turning and the outboard facing tab left our adjuster out of position more than a few times when shuttling or leaning against and/or crashing into brush at the side of the trail. We'd vote for ditching the tab and replacing it with an indexed dial similar to other forks.

Top-out and bottom-out could be improved as well. While we were arguably riding the fork a touch under sprung, the few occasions we did manage to bottom out were pretty harsh feeling. The lower spring assembly has a lot of plastic, and in the right conditions we could make the fork slightly but audibly top-out. Reducing travel by adding the hard plastic spacers to the top-out side seemed to increase the frequency of this happening, but we'd stop short of claiming the fork has a significant top-out problem.

Long Term Durability

We've been riding the Z1 Coil for three months with no leaks, squeaks, creaks, or rattles. The Z1 coil is essentially a FOX 36 Grip damper and seals built into the proven Z1 chassis that was released in 2018 but with a less service-intensive coil spring system. Given the known track record of these components, we don't foresee durability being an issue. By sticking to regular service and adhering to the recommended fluids and levels, the Z1 coil should work well for several seasons.

What's The Bottom Line?

The new Marzocchi Z1 Coil is an excellent fork, full stop. It may not have all the features of a premium or more expensive race-level fork, but it is not lacking in performance. If you want all the bells and whistles this was never going to be the fork for you, and it won't claim to be. If you want the set-and-forget all-weather/altitude/temperature performance of a coil spring, functional bottom-out control, plus simple and intuitive adjustments in a fork that punches above its price point, then you'll have a hard time going wrong with the Z1 Coil. Just make sure the spring rate works for you if you're as picky as we are.

Head over to www.marzocchi.com for more details, and be sure to catch Wade Simmons on the new fork in this Marzocchi launch video:

About The Reviewer

Lee Trumpore - Age: 40 // Years Riding: 28 // Height: 5'10" (1.77m) // Weight: 160-pounds (72.6kg)

In more than a decade of professional DH racing, Lee won a Collegiate National Championship and was a mainstay at major North American races as well as occasionally snagging a last page result in the World Cup series. Testing prototype components and suspension setups was common during his racing days. He has a smooth, light style on the bike even while holding it wide open. An East Coast native, his favorite trails are fast and flowing technical descents with as many corners as possible and just enough moisture to keep things interesting. Nowadays, rather than racing the clock, he'd rather enjoy a rad descent after a hard pedal to the top. He's also a photo mercenary for Vital MTB and other industry clients.