Over the course of the last few seasons we've seen more and more all-mountain and enduro bikes get the coil shock treatment, while in the downhill world there are more bikes equipped with air-sprung suspension than ever. Is there a real reason for this trend, or is it a case of style over substance? That's open to debate, but while the major fork manufacturers seem to be focused on air-sprung options, the smaller players are filling in the void with coil-sprung options of their own.
MRP decided to join the party with their Ribbon Coil, which has a list of features that are nearly identical to their well-received air-sprung Ribbon. The Colorado-based company's fork has externally adjustable compression and rebound damping, spring preload, and it even has MRP's Ramp Control feature, which can be used to increase the amount of bottom out resistance.
Ribbon Coil Details
• Intended use: trail / all-mountain / enduro
• Coil-sprung, soft, medium, and firm springs included
• 35mm stanchions
• Travel: 140-160mm (29"), 150-170 (27.5")
• Offset: 44mm (27.5), 46 or 51mm (27.5+ and 29)
• External adjustments: rebound, low-speed compression, Ramp Control, preload
• Weight (29", 46mm offset): 2240 grams
• MSRP: $989.95 USD
Available in a 27.5” version with internally adjustable travel from 150 - 170mm and a 29" version with 140 - 160mm of travel, the Ribbon Coil retails for $989.95 USD. Details
The Ribbon coil uses the same chassis as its air-sprung sibling (MRP offer a kit for riders who want to convert their air-sprung Ribbon fork to coil), with 35mm stanchions, and the distinctive Outcast arch design, which is designed to help keep mud from building up inside those little pockets during sloppy rides. There's also a small button on the back of each leg that can be used to bleed off the excess pressure that can develop due to elevation or temperatures changes, a feature similar to what's found on a Fox 40 downhill fork. The Ribbon Coil is only available with 15x110mm axle spacing, with either a quick-release style or a bolt on thru-axle to keep the wheel securely in place.
The right leg of the Ribbon Coil houses the same damper that's found in the air-sprung version, a twin-tube design that uses a spring-backed internal floating piston. Low speed-compression is adjusted via an 8-position dial at the top of the fork, while rebound is adjusted via a knob on the bottom of the fork, with 18 clicks of adjustment.
The Ribbon Coil comes with soft, medium, and firm springs included, and there are also extra-soft and extra-firm springs available. There is one quirk to the Ribbon Coil's design that I'm not sold on – the fact that you can't change the spring without removing the fork's lowers. With most coil-sprung forks swapping springs is usually only a matter of removing a top cap and making the switch, but the Ribbon has a tapered stanchion tube that makes this impossible (trust me, I tried). Instead, most of the steps that would be required to do a lower leg service need to be performed just to swap a spring.
The spring-swapping design may be inconvenient, but I am a fan of the fact that adjusting the fork's travel doesn't require any additional parts. There's a lock nut on the spring rod assembly that can be moved to increase the amount of travel, from 140 – 160mm on the 29” fork, and 150 – 170mm on the 27.5” fork.
MRP have also managed to integrate their Ramp Control system in the Ribbon Coil, which allows riders to dial in additional end-stroke ramp up, a feature typically reserved for air-sprung forks. Even though it's a coil-spring fork, there's still a small amount of air in the lower leg. The Ramp Control works by adjusting the flow of this air into the stanchion – turning the Ramp Control knob changes the size of the opening that the air passes through. The nature of the design means that it's speed sensitive – at moderate shaft speeds the air easily passes from the lower leg, through the spring rod, and into the stanchion, but at higher speeds it becomes more difficult for that air to get through the port, which creates that end-stroke ramp-up. Performance
There's a reason air-sprung forks dominate the market – they're light, easily adjustable, and shops and manufacturers don't need to deal with keeping a stack of various springs in stock. But the small bump sensitivity of a coil fork is hard to beat, which is one of the reasons they have such a loyal following. The Ribbon is no exception – it does an excellent job of smoothing out the small chattery section of trail, a trait that's especially handy on wet, rooty trails where having the maximium amount of traction is necessary to stay upright.
That being said, air-sprung forks have become very, very good in recent years, and I wouldn't say that the Ribbon Coil's level of grip is worlds apart from a new Fox 36 or a RockShox Lyrik. The overall sensation the fork delivers out on the trail is different, though, and the Ribbon Coil has a more linear, slightly plusher feel, something that riders looking for extra comfort on very rough trails will appreciate.
I initially started out with the soft spring installed – I weigh 160 pounds, and based on MRP's chart I'm right in the middle of the recommended range for that spring, but the fork bottomed out too easily, even after I added additional preload and Ramp Control. Time for a spring swap. Once I had the medium (green) spring installed the spring rate was much better, and the number of hard bottom out events was greatly reduced.
The Ramp Control dial is simple but effective – the position of the fork's o-ring after hitting the same drop with it fully open and then almost all the way closed showed that it was doing its job. Ramp Control doesn't have as much of an effect on the fork's midstroke compared to adding tokens in an air-sprung fork, which can be seen two ways. On the plus side, the Ribbon Coil's plush, linear feel is preserved even when more bottom-out resistance is added, compared to an air-sprung fork where the ramp up occurs earlier in the stoke. However, that reduced mid-stroke support does mean that at times the fork felt like it dove a little too deeply into its travel for my liking. Chassis / Weight:
Fork stiffness can be difficult to quantify, but I'd say that the Ribbon Coil's stiffness felt on par with a RockShox Pike. I'd had a Fox 36 in place previously, which felt a little more stout, although the difference isn't massive, and I didn't experience any unwanted flexing from the MRP no matter how steep or rough the trail. As far as the overall weight goes, the Ribbon Coil is approximately 180 grams (.4 lb) heavier than a Lyrik or a 36, although that number is less than what would happen if Push's ACS3 coil conversion kit was installed in a 36 or Lyrik. 180 grams isn't a massive amount of weight, although it's something to keep in mind when considering the pros and cons of going the coil route. Damper:
The low-speed compression dial is is easy to reach, and each click makes a noticeable change. I typically ran it halfway through its range of adjustments, which gave me a little more support for popping off the lips of jumps or pushing hard into turns, while still maintaining the fork's excellent small bump compliance. The one downside of the twin-tube damper design is how much noise it makes. It's quite loud when rebounding, and compared to a Fox or a RockShox damper the squelch is noticeable, and a little annoying. Pinkbike's Take