Inside the RibbonTwin-Tube Damper -
You probably know about MRP's chain guides, but did you know they also offer a range of suspension forks? Sure, this isn't news to a lot of people, but if there was ever an underdog in the suspension world, it has to be this relatively small company based out of Grand Junction, Colorado. After all, their trail/enduro fork, the Ribbon, has to go up against the likes of RockShox, Fox, and Manitou, and let's not forget the new Cane Creek Helm or Öhlins' RXF lineup.
MRP has a few tricks up their sleeve to set the $989 USD Ribbon apart from some of their more well-known competitors, including the clever Ramp Control Cartridge that provides speed-sensitive bottom-out control. There's also a twin-tube damper inside, and external adjustments include low-speed compression and rebound, while travel can be tweaked in 5mm and 10mm increments from 170mm to 140mm on the 27.5'' fork and from 160mm all the way down to 120mm on the 29er version, which is how I set up my test fork. MRP Ribbon Details
• Intended use: trail / all-mountain / enduro
• Travel: 140-170mm (27.5''), 120-160mm (29'')
• 35mm stanchions
• Internally adjustable travel in 5mm and 10mm
• Ramp Control Cartridge
• FullFill air spring system
• Twin-tube damper
• Adjustments: low-speed compression, rebound
• QR15 or bolt-on axle options
• 7'' disc post mount
• Nine decal color choices
• Weight: 4.12lb (1.869kg) (120mm, 29'')
• MSRP: $989 USD
Twin-tube dampers have a reputation for being more advanced than a common mono-tube system like what's found in most other forks, but that doesn't automatically mean that they perform better - they're more complicated, more difficult to package, and some might argue more difficult to work on as well. But there's a reason that you'll see the twin-tube layout used on many high-end suspension units in the motorized world: a twin-tube damper is said to offer lower internal pressures compared to a more commonly used mono-tube system, and lower pressures can mean more control over forces and less stress on seals.
This is the Ribbon's twin-tube damper. The black seal head at the bottom of the cartridge creates the second chamber between the stanchion tube and the cartridge body, which is where the twin-tube name comes from.
A twin-tube system is pretty self-explanatory; the damper is a tube-in-a-tube design that sees both filled with oil and the piston working inside of the inner tube. In the simplest of terms, it's constantly recirculating the oil between the two. Unlike the Stage fork's twin-tube damper that made use of an expanding bladder for compensation, the Ribbon's damper gets a spring-backed internal floating piston. MRP says that the IFP is a more reliable, easier to manufacture design, and also easier for a rider to perform a damper bleed.
Air Spring - MRP's previous fork, the Stage, is also air-sprung, but the Ribbon features an entirely different system than its predecessor. Rather than a single Schrader valve and self-adjusting negative chamber as found on the Stage, the Ribbon uses two valves and manual negative spring setup, a system that MRP calls FullFill. These separate valves for the positive spring (at the top) and negative spring (at the bottom) air chambers allows the rider to tune how active the fork is by varying pressure in the negative chamber, much in the same way as on the recently reviewed Cane Creek Helm.
No surprise, MRP has put their clever Ramp Control Cartridge system to use on the Ribbon as well; it adjusts how the fork ramps up in its travel without needing to add or subtract tokens. Instead, you simply turn a crown-mounted dial that opens or closes a very small port. The smaller the port, the harder it is for the air to pass through and vice versa. Think of it as damping, but to control the fork's air spring ramp-up, and it differs from changing the air volume with tokens because it offers speed-sensitive ending-stroke control with adjustable bottom-out, whereas tokens are position sensitive.
We should probably talk about that funky looking arch, shouldn't we? When questioned at last year's Eurobike show as to why it looks so, er, backward, MRP's Noah Sears said that the idea is to simply move the lattice work to the front of the arch to keep mud and crud from building up inside of it, something that their UK clientele have repeatedly requested. Makes sense, I guess, but let's not forget that it also gives the Ribbon a very distinctive appearance, one that sets it apart from a sea of black suspension forks that all look pretty similar. You may not like the exposed lattice at the front of the arch, but there's no denying that the fork stands out...
The Ribbon won't be mistaken for anything else.
The rest of the Ribbon's chassis is pretty straightforward; there are black, 35mm stanchions that make sense given the fork's intentions, and a 15mm thru-axle that can be had in either a QR15 setup or the bolt-on version that I prefer.
There are also a set of buttons on each leg, just below the seals, that are there to relieve any pressure that may have built up from use or elevation change. No more burping your fork by sliding a zip-tie down through the seals.
Riding the RibbonAir Spring -
Those small buttons (left) on the lowers can be pushed to release any built up pressure inside the fork. I prefer a simple bolt-on axle (right), but you can also get the Ribbon with a QR15 setup.
Besides a suggested pressure for your weight, MRP also provides a range of pressures for the negative spring that will change how the stroke reacts, especially at the top of the travel. It works in reverse to the positive spring, with higher pressures in the negative chamber helping to push the fork into its travel, and MRP strongly recommends keeping this pressure within 95 - 110% of what you use in the positive chamber. For a 160lb guy, they say that 80psi is a good place to start, and between 76 and 86psi for the negative spring.
Chassis Performance -
Those numbers worked decently well, but I did find myself looking for a bit firmer feel overall, so I bumped it up to 90psi and had the Ramp Control dial backed mostly out. In the end, however, 85psi in the positive with the orange party dial turned in twelve clicks did the trick, and that's where it's still at today. I'm also running 90psi in the negative chamber to help the Ribbon into its stroke; it doesn't feel mind-blowingly active, but it's as slippery as anything else on the market. The Ribbon's advantage here is that you can easily make it feel however you'd like by tinkering with the positive and negative pressures, and how the Ramp Control dial's speed-sensitive bottom-out control both works in a very different way than tokens and can also be tweaked during a ride. All that makes the Ribbon far more tuneable than its major competition, which is a bonus if you're into that sort of thing,
With its open-front arch, the Ribbon might look a bit different, but its 35mm stanchions, sturdy looking lowers, and 15mm thru-axle add up to a package that feels comparable as far as torsional and front-to-back rigidity. I'd be nice if I could tell you that it was even stiffer, or less stiff, but the Ribbon feels on par with a Pike on this front.
I will concede that, at under 160lb, I'm not exactly Richie Rude in the heft or skills departments, and I have no problem saying that all of these forks - Ribbon, Pike, 34, et al. - feel more than torsionally rigid enough for the very large majority of riders. Would a 36, Lyrik, or Mattoc be even stiffer? Yeah, probably, but I'm not too big time to admit that I don't need more stiffness from this 120mm-travel package.
I asked for my test fork to come with the standard, 15mm thru-axle rather than their QR15 setup, but only because I don't see any reason to need to get the fork's axle off in seconds, and I always have a multi-tool on me anyway. Then again, I don't race enduro or even cross-country that often, so I'm happy with the simplified setup and having to bust out a 6mm hex key. Riders who are in more of a rush to fix their flat tire than I am can opt for the tool-free QR15 setup, and you can even swap between the two if you feel the need.
As for those air bleed buttons that look like nipples, they're cool looking, but I never heard a single puff of air, or noticed a difference in performance, even when going from sea level to three-quarters of the way to the top of Whistler or Blackcomb. But hey, push 'em if you want. Damper Performance -
I've said it before and I'll say it again: the Charger, TPC, and FIT4 dampers are all top notch and leave essentially nothing for the average rider to wish for, just so long as you're not André the Giant or a fourth grader. The status quo works pretty damn well for nearly everyone but there's always room for something that does the job differently, and the Ribbon's twin-tube damper certainly feels different.
There's a decent amount of compression support, even when the eight-position knob is turned all the way to the left, and that only increases as you dial on more low-speed as required - I usually had the knob set five or six clicks out from fully in or backed completely out if it was wet or loose. The twin-tube damper offers a good amount of composure, but the impressive bit is how it doesn't sacrifice small bump compliance, and therefore traction, in the name of being able to stay up in its stroke. Here are some comparisons because I know that's what you want to read: the new Helm has even more support than the Ribbon, but it's also a tad harsh and less comfortable if you're not in a big hurry, while the Pike and 34 are more forgiving than the Helm but also won't stand up in their travel as the Cane Creek fork manages to do.
And the Ribbon? It's like MRP rode all three of those options, took the best of each, and then put those traits inside an odd-looking chassis that I have no problem looking past because this thing works so damn well.
The MRP fork is as supple and active as a new Pike or 34, but with the same ultra-composed stroke that the Helm can brag about. There just doesn't seem to be that compromise between support and the fork's ability to let the front wheel get up and out of the way of even the smallest root or rock, which is an especially nice thing when you only have 120mm as my test fork does.
At the other end of the range, the Ribbon's high-speed damping never felt too heavy or spikey, but it also did well at taking in those 'oh shit' moments when you see the landing fly by beneath you. That's a good thing as there's no external high-speed compression adjustment which, as a chronic knob fiddler, I wanted before I rode the Ribbon at ten-tenths... I was wrong: it's not needed, at least not by me.Pinkbike's Take: