MRP Releases Ramp Control Cartridges for Fox 38 and RockShox Zeb Forks
An MRP Ramp Control Cartridge for a RockShox Pike we tested in 2017
MRP has released new Ramp Control cartridges for Fox 38 and RockShox Zeb enduro forks. Ramp Control cartridges had previously been available for Fox 32, 34, 36, and 40 forks and all the existing RockShox models before the ZEB. The addition of Ramp Control products for long-travel enduro bikes means that now the shreddy trail bike tinkerers will have more options for adjusting end-stroke ramp-up on the fly.
The Ramp Control cartridge replaces a fork’s top cap and volume spacers. It controls the fork’s progression not by adjusting air volume, as the token system does, but by changing the preload, requiring more force to push air into the cartridge as the progression increases.
The cartridge adjustments do not affect air volume so making changes mid-ride is very feasible because the adjustments do not affect air pressure and therefore sag point.
Mike Levy reviewed the first MRP Ramp Control cartridges when they were released in 2017:
 | A big benefit of the MRP Ramp Control unit is that it removes the need for a socket wrench and can be used to alter how a fork feels in mere seconds, making it more likely that riders will adjust their suspension to better suit where and how they ride. But spending $139.95 USD on the upgrade will make zero sense if you're not the kind of rider who thinks about such things. The set-and-forget crew simply won't benefit from MRP's drop-in cartridge, regardless of how effective and clever it is, but those who appreciate being able to tinker with the feel of their fork on the trail will see it as money well spent. |
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MRP damper is a glorified port orifice with sprung blow off a la Motion Control
DSD Runt is a much better investment. Ramp control increases harshness because it makes the spring speed sensitive, ending up with a spring that feels mushy and divey braking but spikes on big hits
Not to mention that the fork has to extend fully after a big hit to reset the ramp control chamber
I find my Ribbon Coil works pretty good, but I dont run any Ramp. Its lighter than a Pike/Smashpot or Pike/ACS3, so Im not expecting 36/Lyrik stiffness.
The damper isnt great, but there are ways around that. Personally, Id sooner have a coil with a so-so damper than an air fork with a great one, maybe the one exception being the Mezzer, F535, or Era. I ran the Runt in a 34 for two years and also spent time on a Mattoc and while triple-chamber/IRT was far better than tokens, coil is far more plush.
If I had one wish for the Ribbon itd be a bladder style, user tunable, independent LSC/HSC adjustment, modular (like DVO), HBO damper.
I think air with an amazing damper and burnished bushings (important) will beat coil. Air spring seal friction can be around 1-2KG static friction. Some of these forks coming out with tight bushings can have 10kg in static bushing friction! A properly burnished chassis will have so little friction that the CSU falls into the lowers under it's own weight. Tight bushings is often overlooked and should be checked to fix harshness. No point changing the spring with all that bushing friction lol. Another thing to check is axle spacing, and make sure the axle is the correct width and not stretching or squashing the fork.
You can use a kitchen scale to measure friction. Next time you take your seals out, check your bushing friction with no spring or damper, see how much force it takes to move!
I recently purchased a mezzer, i have not ridden it yet but once my Banshee Titan frame arrives we will see
Minimised friction+great spring+Amazing damper is the target
But maybe they have improved...wont be buying another unless I get to test it first.
Hydraulic bottom out is a better option imo
dunno, bit like avy hybrid maybe
There is still the seal head friction, and you can't get TI springs that easily.
Hydraulic bottom out is also a gimmick, and ads additional weight. There is already HSC on the high end forks that can control bottom out resistance, and shocks like Super Deluxe and DHX2 both have foam bottom out bumpers.
Hydraulic bottom out adds barely any weight, and is speed sensitive IE the harder you hit it the more of an effect it has. HSC is not position sensitive. Adding hsc to stop bottoming on big hits will have an effect throughout the rest of the travel. HBO is position sensitive meaning it has no effect on the rest of the travel, and cushions big hits without that harsh clack you can get. Again, adding hsc to stop bottoming is a band aid fix that will affect the fork on fast chunky trails. Adding hsc will stop you blowing through the travel, but if you hit it hard it won't stop a harsh bottom out. HBO allows you to set hsc where it needs to be, and covers your ass when you overshoot that 25 foot to flat.
Technically its not foam, its rubber, but yes, its a bumper.
As far as HBO goes, Im of the idea that people should just learn to ride better instead of complaining about the sensitivity or suppleness of their positions. Sure, in theory HBO is better than HSC. In practice, for the people that ride recreationally and don't race, you should just be able to run a stiffer spring or higher psi, and deal with the extra harshenss, because we can all get fitter and stronger.
BMX riders have no issues in sending huge drops with no suspension on tiny bikes with no suspension, so yes, you are correct.
Suspension isn't there for softness, its there for stability, which is why things like HBO don't really matter.
It's literally just a metal cup in the damper tube, and adds what 13 grams
You're correct in that with proper setup a fork will rarely find the bottom of it's travel
HBO is not so you can setup your fork wrong. It's there so that with a correctly setup fork you have an extra buffer for the "oh shit i should have braked for that jump" moments
Again, with your stability thing: A massive hard bottom out to a hard stop will definitely compromise stability
The super deluxe "bumper" is literally just a 3mm or something o ring lol (if that)
So what you're saying is, for a guy like me that sets his fork pressure with whatever my shop air pressure is and then bleeds it off with a nail until it feels good enough, this might not be a wise investment.
I'm running a 180mm 29er Zeb Select with the compression about halfway in.
ShockWiz recommends pretty much the settings I'm running, sometimes suggesting I add a token. Bottoming it out harsh definitely suggests I need more tokens, more pressure noticeably worsens the rest of the travel.
I do love the fork's plush feel and stiffness, which is more significant than I'd expect with my weight, but the bottom out is much too easy to find.
I do ride kind of hard I guess and in a very aggressive position, 50mm stem and a hectic forward bar roll to get more weight on the front wheel, but none of that was an issue for a Lyrik.
I really don't know what I'm missing here, it doesn't feel like anything is wrong with my fork, and I've worked on suspension for 10 years now so I think I know what I'm doing, even the guys at Fluid Function looked me like I'm from a different planet having this issue but the more I talk about it the weirder I find it.
That said, in a 180mm Lyrik with 3 tokens I ran before I measured 3.9 compression ratio while the Zeb with 4 tokens is just at 2.9. (as in the pressure multiplier at bottom out) It's hard to compare numbers and feel but it does sound about like what I'm feeling.
I may be off on what and how I'm riding, the standards in Squamish are pretty high and so are the compressions, still I guess I'm a pretty good rider but nowhere near a pro level. I mostly ride the harder double blacks and the way the Zeb can track on those is just impressive, but when I come a bit funky off a wet slab picking up a bunch of speed, I often get an impact I haven't felt in a RockShox fork since I took the Motion Control out of my Boxxer back in the day.
I just measured the air chamber and found more than enough room for 5 tokens in a 170 setup, which would give a 3.8CR and feels really similar to the Lyrik when measuring (as in being quite an effort to keep bottomed out for reading a measurement) unlike with 4 tokens.
I thought of enlarging tokens to take up more volume before finding out there's more room but now I wonder if the limit is for other reasons than piston meeting tokens. I also wonder if the old red tokens use more volume as they're about 1.5mm larger OD.
Any Sram person here? Will a 170mm Zeb explode if used with 5 tokens for a reason that doesn't meet the eye? And why am I so weird compared to recommended settings?
Though they would not influence the shockwiz calculation, CR around 3.0 is not very progressive ????
I'm not really too sure what would I call "very progressive", I would say the 3.9 definitely was quite progressive on the Lyrik but delivered exactly what I wanted in terms of big hit performance - regularly used full travel but never actually felt it - not once. I really wonder if the Zeb at 5 tokens and 3.8 CR would feel similar but I'd like to know what's the reason only 4 are allowed, would rather not blow anything in case I'm missing something!
I'm wondering if the 4 token maximum (at 170mm) is to limit the maximum pressure at bottom out which shouldn't be an issue in my case but I hate speculating and not knowing something about my bike
Noah, I think you've already answered this in the past... but how does this differ from my Runt? Very similar except the MRP has on the fly adjust whereas my Runt's chambers can both be set to an exact pressure? Anyway, the full volume of the air spring is available in both, which is awesome.
I've heard two different explanations of how Ramp Control works. They both hinge on having an upper air chamber that the spring blows off into. Where what I've heard differs is what the knob does. I've heard the knob closes a valve, which makes it easier or harder for air to pass to the upper chamber for equalization. The other, which I think is the correct explanation, is you adjust the amount of pressure required for the spring to blow off to the upper chamber. I'm sure Noah can pipe up on what the actual mechanism is, I could be wrong on both, I haven't actually disassembled one to see how it works, so I'm just depending on what I've read elsewhere.
In either case, I've had both mechanisms, I've found the IRT/Ramp Chamber/RUNT/etc to work exceptionally well. It reduces that end stroke harshness you get from tokens, where the fork ramps up progressively at the end of the stroke and you get this abrupt end to your travel, rather it eases into the end stroke easier. The issue I had with Ramp Control is that it seemed inconsistent to me, it seemed like the fork was doing the opposite of what I wanted it to (blowing off at the wrong time). Personally, I don't think air springs should be speed sensitive when you have a decent damper, but that's just my opinion. In both cases, the improvement in linearity is, IMO, good for most forks
Here's an analogy of how Ramp Control works:
Consider a party in two rooms, joined by a door. Everyone is in one room because that's where the band is (your main air chamber). In the other room is the snack table and punch bowl (the Ramp Control chamber). The door is open, so getting from the dancefloor to the snacks is no problem, so long as not everyone is trying to get to the snacks at the same time. That's a low-speed compression event with Ramp Control at the minimum setting.
Now, some fresh bacon rolls come out. Everyone wants those puppies so they rush get some. There's a bit of a traffic jam at the door, but the door's wide open so two people can squeeze through simultaneously. That's a high-speed compression event with Ramp Control at the minimum setting. That minor traffic jam is the build-up of pressure in your main air-spring chamber -- it's a bit more progressive.
Now picture the same scenario, but the door is only half-open. Bigger traffic jam. That's a high-speed compression event with Ramp Control at the "mid" setting. Your main air-spring chamber acts a bit MORE progressively.
And finally, picture the same scenario, but the the door is barely open and there's security guard behind it protecting those bacon rolls. A person can juuuuust squeeze through the opening in the doorway only if they turn sideways, but if you push hard enough, the security guard moves, and you can get in without contorting. That's a high-speed compression event with Ramp Control at the maximum setting. It's very progressive, but it's never completely closed (acting like solid stack of tokens of the same volume).
The party-goers are air molecules. The knob on the Ramp Control cartridge controls how open the door is (port size) AND the size of the security guard (the preload strength of the valve).
Thank you for coming to my TED talk.
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The difference is, that this is a stupid idea in concept and execution,
So with slow compression its soft and quick compression its stiffer, so you mean to tell me that wallowing on rollers and into corners, and stiffening on chatter is what you want? No nobody wants that.
The problem with most air forks is that the starting force is too high (a luftkappe is designed to fix that) and if you put enough air to get the mid stroke right, they are super hard to bottom even with no spacers, but everyone likes ramming in max spacers because they think they huck big then they run no air, you blow through half the stroke like nobodys business and hit a progression wall that way the 38 already takes measures to abate alot of this....smaller piston diameter large negative huge positive thanks to the tube In tube design...
The dsd is quite different, but basically you can make the beginning and middle of the stroke firmer and the second chamber gives way preventing over progression. It can be setup progressive or very linear
Also DSD didn't invent the idea of double chamber positive springs.
Plus needs to fully extend to reset. No thx. Gimme irt/runt