Formula Nero C Review
Intro
“The easy way to downhill”.
Preload, clicks, ride.
The Formula Nero is the DH headliner of the Italians’ fork range. This C/Coil version of the fork is the cheaper of the two options costing £1500 while the R version retails at £1750.
I chose the coil fork because I love the feel of steel and it nicely matches my linear coil-sprung frame. A coil always performs best on the trail as you avoid any issues of air transferring into the wrong chambers, heat and altitude changes, extra friction from many extra seals and helpfully needs less servicing. A coil is simply more efficient in every way and has a minimal weight penalty of 230g in this case: the C is a claimed 2840g and the R is claimed at 2610g. Yeah, it's a bit heavier, but I don't worry as I want a robust, high-performance bike that requires minimal maintenance; I also mainly ride with a mix of lifts and pedalling.
The air-sprung R fork comes with a triple chamber air spring with two valves to adjust the different chambers which adds complexity in balancing the pressures and finding your sweet spot. The coil version just needs the correct spring selection and then using the preload adjuster to fine-tune the sag. Formula’s tagline for this fork is “The easy way to downhill.”
Both Nero forks come with a simple damper that avoids the CTS (Compression Tuning System) interchangeable compression units found on most other Formula forks: I assume the reason for this space and weight, the bigger dual crown fork architecture means it is easier to get more shims and oil in there and have a wide range of adjustment. The CTS found on the other shocks and forks is likely used to keep size and weight down but continues to offer a wide range of adjustments for everybody by changing the CTS shim stacks. This Nero damper simply has high and low-speed compression and rebound adjustment.
Issues
So far I have been really impressed with the performance of this fork, but first, there are a few small issues which I also mentioned in the First Impressions article.
The first issue is the 160mm brake rotor post mount. I believe this is because Formula shares the lower castings between their Selva Enduro and Nero DH forks, which is fair to keep manufacturing costs down through economies of scale, especially for a smaller brand. But I think any Enduro or DH fork should be specced with a 200mm brake mount, I don’t know anybody who wants to run a smaller rotor on the front.
The second issue is the FIRM axle system: It does work well by simply tightening up the main axle with a 6mm hex, then on the other side, there’s another bolt that threads in to lock the axle in place. Something for customers to be aware of is the locking bolt uses a reversed threat and the torque ratings are similar: 15nm for the main and 12nm for the locking bolt. A couple of times I have gone to remove the wheel and instinctively tightened the locking bolt, then tried to open it the correct way, but now the locking bolt is too tight and the entire axle is turning. Now you need two 6mm hex keys to crack it open which you might not always have with you. Apart from that, the axle works fine and it was my mistake that I hope not to make again.
The other silly thing I did with the axle was to completely remove the locking bolt each time I removed the wheel and eventually lost the little plastic washer - then I realized you can loosen it and leave it partly threaded in while removing the axle.
The next issue is fitting length. This bike has a 130mm headtube which is on the medium-to-long side of the spectrum fitted with a zero-stack Cane Creek headset: total fitting length is 141mm.
I assumed the “-End Stroke-” line was the safe limit to set the lower crowns, from previous suspension experience if there's a line there, that means it’s the lower limit for the lower crown. I started testing and then nearly killed myself when I bottomed out the tyre into the lower crown, rolled a massive nose wheelie and luckily avoided launching myself over bars. So don't be fooled into thinking that is as low down as you can place the lower crown, it's not. It needs to be approximately 22mm above this height to not bottom out on the tyre - please do your own checks before riding using the Formula manual.
The main reason I won’t be using this fork anymore is that it doesn’t fit this bike correctly which is a bit of an annoyance despite choosing the upper drop crown. If you're gonna buy one of these forks carefully check first what the head tube length is and if it will fit. Formula’s website or manual doesn’t suggest what the max headtube length is (they tell you the minimum axle-to-crown length but that doesn’t help you know it will fit). Of course, this is a DH fork and most current DH bikes have a headtube length of around 110mm so is probably a rare issue.
When it comes to the crowns there are 50mm (used here) and 58mm offset options. Nicely, not too much of the offset is in the fork lowers and more is offset in the crown: this means the fork maintains a good steering lock. I would like to see shorter offsets available but this is not only a criticism of Formula: most DH forks seem to have longer offsets despite single crown forks which are designed for similar use and are generally 44mm like the Fox 38, RS Zeb and DVO Onyx.
Setup
Formula's website doesn’t offer any specific setup for spring rate or starting clicks related to rider weight so if you don’t buy from a tuner you are playing guessing games to get started. I did also speak to Formula directly but they didn’t give me much more information.
I ordered an additional Soft spring which was ideal for my 73kg kitted weight and bike. This came as an extra in the box and it was an easy process to change from the medium stock spring. This soft spring gives me 20% sag with 2 clicks of preload. There are 3x spring options, Soft, Medium and Hard, so riders at the extreme ends of the scales may struggle to find the correct spring.
Formula doesn’t offer any start settings so you can only play guessing games to get going.
If there are no recommended base settings I start with damping nearly fully closed, why? It’s easier to ride a bike that is too firm up to your riding pace and then reduce damping until it is comfortable; opposed to starting with soft damping and then trying to ride an unstable bike up to a speed you are comfortable with. After weeks of testing, I finished up with -6/12 LSC, - 6/20 HSC and -8/21 Rebound. The LSC and Reb clicks are quite difficult to feel on the adjusters so care is needed, but dialled in with these clicks the fork was performing exceptionally. The damper appears to have a wide range of adjustment that should fit most riders, but without a dyno is hard to tell exactly what is available.
On The Trail
This is a really damn good fork. Initial sensitivity is exceptional for a stock fork. I assume the fork being assembled (not made) in Italy in small batches means they take the time to check and size the bushings for reduced friction, I’ve had several Formula forks over the years and they always felt great off the top.
Of course, the coil also helps with this sensitivity and that’s why there are still many coil fans out there. This fork sags around 5mm under its weight, which I always think is a good sign.
Mid-stroke support is also perfect (thanks again coil) and is a dream compared to many air-spring feelings. Remember, however “coil-like” that air spring line is on the graph from the marketing department? Forget it, a coil will always feel better on track.
Bottom-out resistance is also exceptional, which is lucky as it means I’m not bottoming my tyre into the crown. Generally, I can’t use more than 190mm of travel which is ideal leaving 10mm more for those “oh crap” moments.
The fork is not too stiff either, much more flex/traction than a Fox 40 and very similar to the previous 35mm Boxxer series. Overall the chassis feels great except it does lose out to my Dorado when charging and trying to hold a line through angled rough or traversing off-camber. The upside of this stiffness in the lower portion of the fork is a more precise feel in bike park berms and fast, smooth corners.
Performance downsides? The only times this fork struggles is on small but high-speed bike-park braking bumps and some big square edge hits. There’s some noticeable friction and harshness on the fast vibration bumps, and sometimes on harsh edges which can also make it feel like it’s inconsistent. I put this down to the bushes being slightly oversized so they feel great at lower speeds but can bind up when the fork is bending; this is also the reason for brands moving to bigger stanchions to reduce this feeling from the fork bending just like in all those PB ‘Huck to Flat’ videos. I don't think it’s inconsistency in the damper, or binding in other places as the damper is mounted on ‘Internal Floating Technology’ essentially acting like spherical shock bearings allowing the damper to move under side loads. Bushing tolerance is a balance, and I’d prefer it to feel like this fork does: harsh on a few rare occasions and great the rest of the time.
Verdict
This is a fantastic fork, probably the best-performing production DH/enduro fork I’ve ever tested and one that I could happily ride for years without any further tuning. I’ll be keeping this in stock as a spare and maybe it will fit on a newer build in the future. I advise buying one from a reputable tuner who will make sure it fits your bike’s headtube, and that you get the correct spring and some settings advice for a good start.
It does everything you could ask a fork to do from the start to the end of the stroke and at any speeds. It’s more set-and-forget than air forks and works consistently in all conditions, from hot and cold, changing altitudes and track surfaces. It’s also suffered at least 20 days of riding and still feels like new.
Is it as good as my Dorado RRT or my customised coil-sprung NSR damped Rockshox Boxxer? Not quite, but it’s not a €2800 Dorado RRT or a tuned Boxxer costing over 2k. At £1500 it is cheaper than all of the competition (comparing RRP prices in Europe) except a Marzocchi 58 and I believe the only fork from the major brands assembled in Europe (I have no problems with Asian manufacture, it just simply costs more to assemble things in EU/USA than in Taiwan).
Well done Formula, a really good job. I’m interested to see what you come out with soon as this fork has been on the market since 2017 and I guess it will be further improved and updated soon.
Great! But, is this an independent review?
Yes, it is and it’s funded through my competition site. Until the 18th of December you can win a Formula Suspension package fulfilled by ELRO Distribution in the UK: the lucky winner will receive any fork + shock + brakes of their choice with some spares thrown in for good measure. ELRO is also run by a cool guy called Paul Shepard who is a renowned suspension expert after working at Mojo and Geometron for years so you know he will get you the right products for your bike.
All you need to do is answer a simple question and you have an extremely good chance to win: current odds at the time of publishing this article are 1/91!
As always, all prizes are for BRAND NEW products, in a choice of size/spec/colours to suit the rider and their bike.
Global shipping is also included so entrants are invited from anywhere in the world.
The giveaway is guaranteed to happen on the end date regardless of how many tickets are sold. No extensions, no minimum ticket sales.
These competitions fund my reviews which I believe are the only truly independent MTB reviews online. All of the prizes and all of the products you see are bought by me - no sponsored posts, no freebies and no back-handers.
Thanks, Paul.