MANITOU DORADO PRO REVIEW

THE RETURN OF THE FORK THAT TURNED DOWNHILL UPSIDE DOWN

Review & Photos by Ryan Cleek

Upside down, or inverted, dual-crown forks have been staples in dirt bike suspension for decades. In the world of downhill mountain biking, they’ve had some moments in the sun. Yet, for a variety of reasons, such as: cost to produce, reliability, and questionable torsional stiffness they’ve largely gone the way of the dodo, for one exception: Manitou’s Dorado. Off the top of my head, since the turn of the century I recall inverted, dual-crown forks floating in the downhill ether from Marzocchi, Stratos, Risse, White Brothers, DVO, Avalanche, RST, Mr. Dirt, BOX, Foes, Showa and Kayaba (made specifically for the Honda RN-01 G-cross team), plus a quick online search today brings up a surprising number of current off-the-shelf upside-down downhill forks from the Chinese company, FastAce, available on eBay. So, there’s never been a shortage of attempts at reliably producing this style of fork.

To be blunt, whether in the lift line or online, these days rarely is Manitou’s Dorado a part of the downhill fork conversation. However, over the last 20-plus years few mountain bike components acquired a following like the Dorado. In retrospect, the fandom was likely due to the fact it was being raced as a prototype on the World Cup by high-profile, factory riders, such as: Eric Carter, Greg Minnaar, Kirt Voreis, Nathan Rennie, Cedric Gracia, Sabrina Jonnier, Anne-Caroline Chausson, Chris Kovarik, and Tara Llanes, among others, from 2000 to 2002.

In my estimation, the years when the Dorado was exclusively raced under elite factory riders also coincided with the rise in popularity of many mountain bike message boards where discussions on prototypes ridden on the elite race circuit took off, which only added to the fork’s mystique.

The RockShox Boxxer was the most dominant fork in downhill for many years prior to the production release of the Dorado in 2003. And, despite the Fox 40 (commercially released in 2005) making significant headway in the World Cup and World Championship downhill victories under the likes of the Rachel and Gee Atherton; Aaron Gwin; Tracey Moseley; and in recent years, Greg Minnaar, the Boxxer likely still has a significant upperhand in terms of overall World Cup victories. I’m no statistician, so maybe the downhill tally between RockShox and Fox is closer than one might think. Regardless, for a brief window in the history of elite downhill racing the Dorado took its share of scalps. Conversely, it’s possibly been decades since it was last ridden to an elite World Cup downhill podium.

Ryan Cleek racing the original Dorado at Northstar in Tahoe in 2003.

These days, I’m in my 40s and have been racing downhill mountain bikes since 2000. Although I don’t race 20-plus times a year as I did when I was an LA-based young buck, I still regularly compete west of the Rockies and typically ride my big bike in bike parks on summertime weekends when not running a number plate. For what I lack these days in youthful enthusiasm I like to think I’ve replaced with perspective and knowledge. Coincidentally to that point, I recently came across a photo of me from 2003 racing at Northstar in Tahoe on the first-generation Manitou Dorado, and it turns out I raced the entire 2022 Northstar Downhill series aboard Manitou’s latest Dorado Pro fork reviewed here.

Manitou of today is a completely different company than what it was back when the original Dorado was introduced into the sport. That first-gen Dorado was given to me for a magazine write-up by then Director of Manitou Sales, Marketing, and Product Development, Joel Smith. In those days, Answer / Manitou was based in Valencia, California, which is a northern suburb of Los Angeles. In 2006, the owners of Answer / Manitou sold the brands to Wisconsin-based Hayes Bicycle Group, which along with Hayes brakes, also now owns Manitou suspension, SUNringlé wheels, Reynolds wheels, and ProTaper components.

According to Smith, who is now the Brand Leader for Reserve wheels made by Santa Cruz Bicycles, and was also previously the General Manager of X-Fusion suspension, the original Dorado was raced on the World Cup circuit as a prototype for a lengthy period of time for a variety of reasons.

“Our goal with the first Dorado was to create a lighter-weight and stiffer dual-crown downhill fork,” explains Smith. “As I recall, that first Dorado was raced as a pre-production, factory version on the elite race circuit for a full two years before it was brought to market. So, a unique-looking fork ridden by some of the sport’s top riders and with no known date of public availability certainly added to its allure.”

The Dorado has always been one of the most unique and high-performance-looking forks in the downhill game, and a lot of that slick aesthetic is derived from the carbon upper tubes.

“It’s important to remember the use of carbon on mountain bike components at that time was in its infancy compared to today,” said Smith. “The original Dorado had full-carbon upper tubes, so simply getting strong and reliable carbon tubes was a challenge. In fact, there were many aspects of bringing the original prototype Dorados to production that were pretty gnarly from a mass-production manufacturing perspective. For one, the seals back then weren’t as good as they are today, and since the oil in an upside down fork basically sits on the seals, the early Dorados would tend to leak. Also, we were building each of those forks being raced on the World Cup by hand in our Valencia facility, and every part was sourced from manufacturers in the U.S. The first years of the Dorado’s existence the forks were purely factory race forks for our top riders. Each one was built by hand, and then also rebuilt and tuned for each rider for each different track. In those days at Manitou our brand was “racing,” so putting all of that effort into supporting the racers was expensive, but it was also where our brand focus lived. Ironically, our inability to quickly bring that complicated fork to mass-production increased its allure to the public.”

In 2003, any interest “everyday” riders had in that first-gen production Dorado was amplified when the same year it became publicly available, Greg Minnaar won his first Downhill World Championship aboard aboard a Dorado mounted to an Intense-built Haro downhill bike, and soon thereafter Cedric Gracia would win the Red Bull Rampage on a Dorado-equipped Cannondale Gemini. Smith told me that once finally released to the public in 2003, all of that pent-up customer anticipation for the Dorado combined with the aforementioned success at big events then gave Manitou its best sales year to date.

Aside from being aesthetically intriguing, running an inverted downhill fork has some inherent performance advantages. For one, moving the mass of the lower casting, which holds the lubricating oil, seals, and bushings up higher toward the fork crowns reduces the sprung weight hanging from the fork legs which can improve the fork sensitivity. The upside-down construction can also increase the fork’s front-to-back stiffness (felt under hard braking), as the larger stanchion tubes are now up top inside the fork crowns, plus the lubrication fluids sit atop the seals rather than pooling at the bottom of a traditional fork casting, therefore the seals and bushings tend to stay more lubricated making the fork supple in the initial part of the fork travel. That first Dorado, which ran on 30-millimeter stanchions, had a variety of issues that were addressed in the prototype phase, such as improving the torsional stiffness. That’s when Manitou implemented the Hex axle. Ultimately, for the Manitou of those days to have a mass-produced, consumer-ready Dorado, it didn’t actually meet their goal of creating a lighter-weight downhill fork, but it did have noticeably improved front-to-back stiffness and a look that to this day turns heads.

Enough looking in the rear-view mirror; let’s jump forward to today and dive into what makes the new Dorado’s features, the setup, and how it performed mounted to my 2021 YT Tues 29 Pro DH bike.

THE LAB

Manitou’s latest Dorados were released in mid-2021, and three models are available: Pro ($1950), Expert ($1550), and Comp ($1300), which are offered in both 27.5” and 29er wheel options. Both the Pro and Expert have dual-chamber air-springs, while the Comp utilizes a coil spring. The new Dorados feature 37-millimeter stanchions and the travel on the Pro and Expert models can be internally set to 180, 190, and 203 millimeters. The Expert and Comp versions utilize tapered aluminum upper tubes, and Manitou says they’re also approved for e-bikes. From axle to crown, all new Dorado models are more torsionally stiff than the previous generation, but since this write up is focused on the Pro, from here all features and setup-related intel will primarily be oriented around the top-shelf Dorado.

Manitou says the 37mm stanchions, new carbon upper tubes and overall revamped fork design results in a Dorado Pro that’s over 25% more torsionally stiff than its 36mm stanchioned predecessor. This is important, since torsional stiffness has been one of the ever-elusive flies in the inverted downhill fork ointment. The original implementation of the Hex axle was a key factor in helping to improve the original Dorado’s torsional stiffness, and the latest Dorados feature a 20x110mm floating Hex Lock axle to help keep the front-end on track. According to Manitou’s Product Manager, Phil Ott, the improved stiffness and overall performance for the new Dorado is a culmination of efforts, not simply slightly increasing the stanchion diameter size.

“Everything plays into improving the Dorado’s performance,” explained Ott. “This means, stanchion diameter, crown design, the new dropouts, plus the upper and lower leg design. To measure these characteristics, we have used strain gauges with our data acquisition systems while the bikes are being tested both in the lab and in the real world underneath top-level riders. The important thing to remember with data is how those measurements translate into real-world feedback, such as what the stopwatch says.”

Unlike the original prototype Dorados over 20 years ago, these days the current versions aren’t seen too often on the World Cup circuit. I watch all of the races (and many of the practice and qualifying vids) and only recall seeing one being raced in the 2022 season mounted to the new Forbidden downhill bike. However, according to Phil Ott, the Gamux team raced the Dorado mounted to their unique gearbox downhill bike in 2022 and will be doing so again in 2023.

So, what actually is going on inside the snazzy looking Dorado Pro? Let’s look at the air spring, the compression and rebound damping systems, the pressure release valve, and how to get the riding in the ballpark of your liking.

The Dorado Pro air spring system uses a balancing valve that Manitou says equalizes the positive and negative air chambers when the air spring is pressurized. This is said to give the spring rate a consistent feel through the stroke for riders of all sizes.

To fine-tune the spring rate, Manitou has implemented what they call the IRT (Infinite Rate Tune) that is intended to provide advanced spring tuning by independently adjusting air pressures at the beginning and end stroke of the fork. Manitou says the IRT creates a secondary positive air chamber that only affects the middle-to-end stroke of the fork. The goal of the IRT is to allow lower air pressures in the main air spring for better small-bump sensitivity and suppleness, while the IRT ramps up to handle mid-stroke support and moderate to aggressive end-stroke ramp-up. Rather than adding “tokens” to reduce volume in an air spring to create a desired ramp-up effect, think of Manitous IRT air chamber as allowing tunable mid-stroke and bottom-out control by pressurizing a secondary air chamber.

The Dorado Pro’s compression damping is handled by Manitou’s longtime damping system, TPC+. This sealed, twin-piston cartridge is a velocity and position-dependent damping circuit that is designed to maintain light damping over small bumps that deliver high-frequency impacts in the initial part of the fork’s travel. As the fork compresses deeper into the travel a secondary TPC+ circuit engages and increases damping force for added support and bottom-out prevention. Additionally, Manitou says they use an independent hydraulic bottom-out circuit that further increases damping force in the final 30mm of travel to soften harsher, full-travel hits. A new TPC+ cartridge design has a spring backed IFP (internal floating piston) that Manitou says fully seals damper oil for the most consistent damping on long and demanding DH runs. The spring-backed IFP has improved performance during aggressive riding over harsh impacts, and unlike a bladder, an IFP pressurizes the oil at the initial stroke eliminating any cavitation for a consistent damping feel.

Every new Dorado has what Manitou calls the TSR bleed ports. Standing for Trail Side Relief, the Pro utilizes little red buttons atop the fork legs to relieve built-up pressure similarly to what Fox and RockShox forks currently use on their fork lower castings for the same reason. The Expert and Comp editions have the TSR feature, however the pressure is released by loosening a screw that’s in the same position as the Pro’s red button.

The Dorado Pro 29 ridden here weighs 2975g, which is about 6.5 lbs. All of the new Dorados are currently available directly through hayesbicycle.com, or through Manitou dealers.

THE DIRT

Setup | Out of the box, getting the Dorado Pro dialed-in was a bit of a different process than with a “traditional” fork. For example, I’d been running a Fox 40 prior to installing the Dorado, and to dial-in the 40 one sets the proper air-spring rate for proper sag and desired feel, and then through feedback from riding adjustments to the rebound and low-speed and high-speed compression settings are made to achieve a desired performance. Also, volume-reducing tokens are added or removed during this process, if necessary. With the Dorado, the process is a little bit different. First, as I mentioned there are two air chambers instead of one. Manitou says the IRT air chamber that controls the middle and end of the stroke must be filled first. Manitou’s site has a variety of handy PDF charts that I saved to my phone to have with me while dialing in the fork at the bike park. In riding gear, I’m probably close to 160 pounds, and through trial and error I ended up settling on 115psi in the IRT chamber and 57psi in the main air-spring. In their Dorado Setup Guide, Manitou also gives suggested settings whether someone is casually riding a bike park or shuttle trails, for racing and aggressive riding, and also for boosting big-mountain-style jumps. I started with the recommended compression settings and ended up adding a few clicks of high-speed compression and also made the fork’s rebound a bit faster than the recommended starting point.

With both the IRT and the high-speed compression designed to address harsh, full-travel impacts, how does a rider differentiate whether to add more air to the IRT chamber or to add more clicks of the high-speed compression dial at the bottom of the fork leg (which, I found to be a doozy to turn at times)? Manitou’s Ott explains the differences and when to potentially use more air pressure or more clicks of compression: “A lower IRT pressure can allow the fork to use more travel easier giving a more linear setup. This setup is one riders may want for more natural terrain without as many big hits as what is found on a DH race course or in a technical bike park trail. For steeper terrain or riding high-speed and very rough tracks, increasing the IRT will allow the fork to ride higher in the mid-stroke, which leaves more travel in reserve for bigger drops, jumps, and holes in a track. After a rider has established a good baseline air spring setup with proper ride height and use of travel, then using the compression settings to fine tune the fork behavior is the next step. In general, using the HSC to help the fork use less travel on big hits, or ride higher in choppy terrain, although this may produce some undesired harshness that a higher air spring pressure could help solve.”

Within a day of bike park riding, I had the Dorado Pro very close to the settings I ended up running by the end of the race season. There were a few tedious and potentially problematic matters I encountered when I first began riding the Dorado. First of all, with fork legs that spin and slide up and down independently, installing the front axle will take some getting used to. Eventually, to reliably and quickly get this achieved I just flipped the bike upside down on the ground and moved the independent fork legs up, down, or rotate them to align correctly as I installed the axle. Also, on the Fox 40 I took off my bike I felt I had the front brake hose at about the shortest possible length and still be dependable. However, once the Dorado was installed the brake hose looked a bit too long and bowed out to the side of the fork when compressed. I tried a variety of make-shift zip-tie attachments to the upper legs but nothing really did the job. Without cutting my brake hose shorter, I found the Dorado’s brake hose mounts, which include a zip-tie mount on the stanchion guard and a plastic hose guide that bolts onto the lower crown to do an insufficient job of keeping the hose in check. That said, perhaps if I cut my already short front brake hose a bit more it might make the Dorado’s cable management better than my initial impression. (You can see in the photo of me racing the Dorado last summer the brake hose was bowing way out, and like I said the hose was already very short when mounted to the Fox 40.)

Speaking of the axle, after installing it correctly and snugging down the axle pinch-bolts, during the first weekend of rigid the Dorado Pro I kept realizing the front axle would be loose, well, actually I’d hear it rattling, which then sparked a closer examination. Both the axle and pinch-bolts were tight, but one of the independent legs (which can spin completely around) would begin to “twitch” just a few millimeters side-to-side. This was confusing, because as I said the axle used to pull everything together was tightened to spec, and then pinch-bolts just provide a layer of security for the axle staying put. To remedy this, I installed and tightened the axle as anyone would, then while the bike was flipped upside down, I’d press the fork leg without the pinch bolts next to my left thigh and use my left hand to press the fork legs together along the axle. While doing this I would then snug down the pinch bolts as I sandwiched the fork legs and axle between my left hand and thigh. Perhaps just some tolerances were off a smidge which is why the fork leg was able to “flicker” a bit when everything was tight. Regardless, this trick I came up with resolved the issue. Never again did that fork leg come loose and rattle, but every time I took the front wheel off, I had to repeat this same procedure.

Performance | So, after all the blabbering above you’re probably wondering how the damn thing rides. After seven race weekends and beating it down in the bike park nearly every weekend from June until October, I can confidently say the new Dorado certainly has some impressive ride qualities. But first, let’s address the upside-down elephant in the room: the fork’s torsional stiffness.

Look, with the Dorado (and presumably any inverted fork) if you put the front wheel of between your knees and crank on the handlebar side to side does the front wheel look a bit noodly? Yes, but that’s not really an accurate measurement of fork stiffness in the same way holding the seat with one hand and cranking the rear wheel side-to-side is an accurate way to measure frame stiffness. Because, multiple things are flexing in these scenarios, like the spokes, rims, and tire sidewall, to name a few. Also, fork stiffness preferences can be all over the map. From both former World Cup downhill champions and also well-known suspension brand honchos, over the years I’ve repeatedly heard the story about 10-time Downhill World Champion, Nicolas Vouilloz, who won many races aboard his V-Process downhill bike that ran an inverted BOS fork, testing a new “traditional” downhill fork from a well-known suspension manufacturer. As the story goes, Vouilloz, who’d had a ton of success aboard inverted forks in his day, asked the mechanics if they could take a saw and cut the brake arch out of the fork because the front-end of the traditional fork was too stiff and he found it was deflecting on roots and rocks and therefore difficult to control. Additionally, earlier in this piece I mentioned guys like Nathan Rennie and Greg Minnaar, who not only are World Cup Downhill champions, but they’re both quite big fellas well over 6-feet-tall who raced World Cups on the 30-millimeter stanchioned Dorado prototypes with a great deal of success. My point is that fork stiffness can be a moving target and different riders have different preferences. That said, from my own experience on the Dorado Pro, I did have a couple of very silly slideouts this season where I simply lost the front end on slippery, dusty corners. Then, when getting back on the bike I realized my handlebar and fork crowns were no longer aligned correctly with the front wheel. Yes, this can happen on a traditional downhill fork, however the couple of times that it happened to me they were not high-speed impacts, and I don’t feel a traditional fork would’ve ended up misaligned in the same manner. Those instances got my mind working overtime wondering if the fork could easily become misaligned, well then what’s it actually doing beneath me when I’m leaning hard on it between roots, rocks, and in the face of big jumps? That said, when charging technical terrain on race runs or doing lap after lap in the bike park, I never felt the front-end to be noodly or wandering. Furthermore, I’ve personally heard from many high-level pro riders that sometimes in slippery roots and rocks they like the feel of inverted fork because it’s not so torsionally rigid and allows the bike to almost slither through those sections of terrain. To each their own…

On paper, the Dorado Pro is about 6 ounces (170 grams) heavier than the Fox 40 I took off my downhill bike, however the Dorado rides a lot lighter—I’ll explain. The most evident aspect of this is how braking bumps and high-frequency trail chatter seems to disappear. With the mass of the inverted fork sitting up by the crowns there’s not a lower casting full of oil, bushings and seals hanging down near the axle that the suspension has to manage (a.k.a. sprung weight). From my riding impression, this makes the front wheel feel like it flutters over chattery terrain, like braking bumps.

For as supple as the Dorado Pro is on the high-frequency trail chatter, when it comes to big impacts it can easily be set up to handle them smoothly as well. The ability to fine-tune the IRT that controls the mid-to-end stroke of the suspension really allows the front-end to predictably take the brunt of harsh, head-on impacts from rocks and roots without using more travel than needed. By the end of my first full day riding the new Dorado I had it completely balanced with my Fox coil shock and from that point only made small tweaks throughout the rest of the season. Whether charging high-speed berms or navigating tight switchbacks, the dual-air spring combination along with the TPC + and HSC damping controls allow the Dorado to ride in the sweet spot of the travel, rarely diving under braking or when weighting the front-end in high-speed corners.

The Wolf’s Last Word

The Manitou Dorado Pro is a top-shelf downhill fork with a spendy price tag. Relative to Manitou’s main competitors in the suspension game, there have never really been a lot of Dorado forks out in the wild. However, what it lacked in sales numbers over time has made up for in its allure, unique aesthetic, and undeniable performance benefits. When I initially put the Dorado Pro on my downhill bike, I anticipated riding it for a month or two and then going back to my prior fork, which I had dialed. However, as the 2022 season went on I found myself liking the Dorado more and more, and before I knew it there was snow on the ground and it was still mounted to my downhill bike. Ironically, I would have never guessed 20 years after reviewing the very first Dorado I’d be writing up another generation of the fork, however I’m glad I had the opportunity, because it exceeded all of my expectations, and it just looks damn cool, too.

Price: $1,949.99 /£1,699.99
Weight: 2,975 grams (Pro/29)
Website: Hayesbicycle.com