MRP's Boost Solution and New Ramp Control Cartridge - Interbike 2017

Sep 19, 2017
by Mike Levy  
Interbike 2017


Interbike 2017


Today's suspension forks work pretty darn well out of the box, and you can't really go wrong if you're spending the big bucks on a high-end fork from one of the main players. That fact pretty much killed off the aftermarket fork hop-up business many years ago, but there are still a few upgrades that make sense, one of them being MRP's pint-sized Ramp Control Cartridge.

We've shown you this thing before, and I've even reviewed one back in February, but MRP keeps adding versions to fit more and more forks - the one pictured here is their latest, and it goes inside of any X-Fusion fork with 34mm stanchions.


Interbike 2017
Interbike 2017


When it comes to adjusting ramp-up and bottom-out resistance, you're likely picturing either tokens or some sort of system where the volume of the air chamber is altered by turning a dial to move a piston up or down. And, with an orange knob on top of the cartridge, it sure looks like that's what's going on with the Ramp Control Cartridge. But that's not how it works. Instead, the orange knob adjusts the preload on a small air port at the bottom of the cartridge. Adding preload means that it requires more force for air to enter the cartridge, and that means more bottom-out resistance. Less preload lets air transfer from the fork's normal air chamber and into the cartridge easier, so you'll have less ramp-up.

There are no volume-adjusting tokens involved, and the Ramp Control unit creates speed-sensitive control as opposed to position-sensitive as tokens do.


Interbike 2017
Interbike 2017


The move to Boost spacing was a real pain in the ass for a lot of riders, and especially those who own expensive wheelsets that they'd prefer to move to their next bike, or if they wanted to buy a new fork but it was only available with Boost axle sizing. And those riders are 100% right to bitch about Boost - yes, there are some clearance advantages at the back of the bike, but there's essentially zero perceptible difference in rigidity between a non-Boost and a Boost fork. So, what's a person to do?

MRP's Better Boost Adapters might be the answer, but only if you have a DT Swiss, Industry Nine, or Stan's front hub (a Hope version is coming soon). The kit includes two anodized orange hub end caps that replace the stock caps, and a spacer that moves the rotor out from the hub shell. Longer rotor bolts are also included. Unlike some kits, MRP's end caps are captured and won't fall out when you take your wheel off, and you won't need to re-dish the wheel, either.






103 Comments

  • + 151
 MRP is doing some rad shit right now!! Keep up the great work and somebody punch Simcik in the leg for me!!
  • + 51
 For real, for how much we like to bitch about changing standards and expensive parts, MRP seems to be one of very few manufacturers that seem to put what rider's want first.
  • + 27
 @pbfan08: Cleaning up SRAM and co's mess you mean? f*ck Boost, f*ck 15mm axles, f*ck torque caps, f*ck boost 20x110..the list goes on.
  • + 3
 that boost kit is quite nice, however, I'll rather opt for the simpler available versions with just the right side endcap being replaced. Downside is that you need to redish your wheel 5mm (spoke lenght change is below 1mm, so that's not an issue), benefit is that the spoke angles are almost symmetrical then, which is beneficial for the overall disc stiffness and durability.
  • + 7
 @pbfan08: it's not just giving what they want, its looking ahead to what they'll need.
  • + 14
 But why not make it black?
  • + 1
 @MatthewCarpenter: I agree with you. Is there really no one doing that already? I have to look it up but I thought Formula made her latest forks "Boost ready" or something like that so that these could basically take both 110x20 and 110x20 Boost hubs. Not sure about 110x15 boost.

With all the bitching people seem to forget that axles in particular haven't been too standard. We've had Curnutt with a 30mm axle, Specialized used a 25 for their dedicated USD forks for their Enduro frame, then I think B1 used a 165mm rear axle even in their 4X fully. It is just that at some point we got some pretty big OEM players, SRAM in particular. So their choices have become pretty prominent and determine what others do (though 100x15 was from Fox. onepointfive from Manitou and even Syntace is more influential than some might think). But it seems things are stirring up again. Other brands are stepping up and more high end bikes are being equipped with X-Fusion, Suntour and Manitou is back too. Maybe even RST at some point.

So yeah SRAM has been pretty wild with standards lately but it is pretty easy to ignore them nowadays (and still ride an up to date bike).
  • + 4
 @jrocksdh: Yeah for sure. Great kit, but at least make black an option.
  • + 5
 @jrocksdh: Branding
  • + 4
 @MatthewCarpenter: Do we really want the average bike owner trying to redish their wheel?
  • + 1
 @ea82abuser: Shouldn't be too hard? If you can't true your own wheels, your lbs should be able to do it for you. It needs to be done anyway.
  • + 1
 @MatthewCarpenter: uuuh who? and who wants to redish say an Enve wheel with internal nipples?!
  • + 1
 @bonkywonky: Boost was mainly Trek, 15mm was a collab between Fox and Shimano, and Boost 20x110 was originally DVO. And Torque caps work with normal hubs too. I honestly can't think of something in the last few years outside of Metric and XD drivers that SRAM has released that has forced a major standard change.
  • + 1
 @pbfan08: I feel like MRP should be the go to company for manufacturing companies to better their designs. MRP continues to find what is missing and applies it through manufacturing aftermarket parts.
  • + 41
 My simple answer to all the new standards that are being pushed out in order to facilitate "forced" upgrades. No new bikes for me for at least 5 years. I'm buying used crap till my bike falls apart.
  • + 67
 I was attempting to keep up with standards until things just got too ridiculous; my slightly dated stuff is now too worthless to sell and allow me to upgrade anymore. The industry broke the sweet spot where it was possible to keep up for a few bucks a year. I'm cool with spending nothing now instead. Good job, industry peeps.
  • + 23
 exactly this!
when we point this out an people say "well no one's forcing you to buy it"
an we don't buy it....
an ultimatley LBS an small parts cpmpanies suffer

but hey Ebikes eh?..................
  • + 20
 And manufacturers wonder why sales have flatlined.
  • + 5
 same here!
  • + 14
 I buy peoples used shit and love it. I wouldn't be able to afford the bike I have brand new by a long shot.
  • + 3
 I can see the desire, from a design and manufacturing perspective, to go wider with the rear spacing and BB spacing. Its like metric shocks- annoying, but there is a purpose. HOWEVER there already are several wider standards than 142!!!!!
  • + 5
 I waited until this year to buy a new bike for this very reason. My bike has boost front and back, eagle, and is mostly up to date. We'll see how long it lasts. Considering I'm worried about the bike being outdated 6 months after I bought it is a pretty good indicator of where the industry is at.
  • + 3
 I just buy everything. EVERYTHING!
  • + 10
 @tgent: Many moons ago, I purchased a Yeti SB66 with all the fixin's and all my hard earned.
Three days later, Yeti announce the new SB6 for the same price.... It was brutal
  • + 2
 @Waldon83: Too funny. I had the exact opposite feeling when they released the SB6 right after I picked up one of the last SB66's. But then again, I am a whore for the "tiny" wheels.
  • + 9
 @ninjatarian: This x1000 When $2,000 wheels become antiquated and non transferable in 1 year, well the industry lost my $3k frame upgrade every 5 years. Now they can go F!ck themselves for their 10mm additional spoke bracing angle that nobody can feel anyway and guys are detensioning their wheels for less rigidty anyway! The industry incrementalized themselves right away from my wallet.
  • + 1
 @Waldon83: Lol I hear ya man. I thought about it a bit more too, my bike doesn't have metric shock sizing, so I'm guessing I'll be unable to buy a sweet new shock in about a year. Oh wel! I'm planning on keeping this bike for years, so oh well.
  • + 1
 @jclnv: bingo. Our highc end customers have over it, sick of the hassle, being able to change frames for them was easy and so trying new ones wasn't too painful. Now they're Fed up with the changes for no reason and are going back to alloy frames, over the carbon hype.
  • + 1
 @tgent: yeah, I'm not unhappy with my bike by a long shot (now on a SB6c)
I went boost front end just so I could have the Cane Creek Helm to match my Double Barrel CS Coil rear end..... but I'm not buying into any more gimmicks
  • + 3
 Yeah, to me something new at least has to "prove" itself that it is going to stay. Rapid Rise is probably what drove people towards SRAM back in the day so Shimano moved back to normal eventually. When Shimano released the Saint group one year later you needed their Saint hubs to mount their oversized centerlock rotors. Onepointfive, not sure how long that lasted. Eventually it evolved to tapered though. Silly bunch of bb standards once they decided to move away from square taper. It is just like with computers and cellphones these days. It is silly to be an early adopter. You just spend more money on something that's likely to be obsolete in a few years from now. Thing is, digigeeks know and expect this. Us mountainbikers (from what I gather here) need something that works, performs and can be fixed if it goes wrong. Marginal improvements aren't worth much unless you're competing at the very top. Which inherently very few do.

I don't think it is all about forced upgrades though. Syntace for instance has been very considerate. They came with 142x12 to give you the same convenience in the rear as we already were used to in the front. And they did it in a way that allowed for many hub brands to just swap the end caps and your hubs were up to date again. Same with their EVO6 take on the boost spacing. Boost was already there, they just made it more useful. Something similar could be said about 110x20 (the original). Really it really took different end caps to squeeze the same hub in a 100mm wide fork the flange spacing and bearing spacing wasn't optimally utilized and the extra width of the original 110x20 hub was pointless.
  • + 18
 "but there's essentially zero perceptible difference in rigidity between a non-Boost and a Boost fork"...Blasphemy Mike! You'd better fall in line otherwise mfgrs may stop sending you stuff to test! Haha!
  • + 11
 Air is a fluid.
  • + 9
 This has been out for much longer
www.wolftoothcomponents.com/products/boostinator
  • + 2
 I feel like the prices went up when Wolftooth started producing them after Lindarets.
  • + 8
 What is all this strange stuff? I'm still on qr 26".
  • + 3
 "Today's suspension forks work pretty darn well out of the box, and you can't really go wrong if you're spending the big bucks on a high-end fork from one of the main players. That fact pretty much killed off the aftermarket fork hop-up business many years ago... "

Yeeah... Not quite.
  • + 6
 That's a good looking hand.
  • + 4
 No kidding. Sturdy, but yet with a touch of grace. Give that hand a job to do.
  • + 6
 Hell yeah hope version in the works, sign me up
  • + 3
 with that orange color it will match my hope hubs
  • + 0
 "you won't need to re-dish the wheel, either."

that's not a good thing. yeah, it saves some time, but if given the opportunity to make your wheel stronger, why pass that up?

thats why the wolftooth/lindarets boost adapter is superior. you DO need to redish your wheel, meaning you'll have a stronger wheel as the drive side spoke angle gets less extreme
  • + 11
 If your someone with a stable of bikes with varying hub standards, it's nice to be able to swap wheels around without redishing.
  • + 16
 Why would I want a wheel with 'better' spoke angles if my wheels held up nicely with 'bad' angles for years and maybe end up buying new spokes and having the pia from redishing?
  • + 7
 @Muckal: Your common sense is why we can't have nice things.
  • + 7
 You can install our adapters without dishing, heck, without much more than mallet and T25. Some people prefer this ease, and are pleased with the stiffness of their current wheel. We're pleased to give you our solution as an option.
  • + 1
 @NoahColorado: Hadley, please!!!
  • + 1
 @PHeller: that's a good point, i hadn't thought of switching back and forth, only future proofing for the next frame

@Muckal obviously we've all survived this long before boost, but there is absolutely nothing wrong with an even stronger wheel. i really wish more rim makers would go asym for even better spoke angles. the WTB asym is the stiffest non-carbon wheel i've ever ridden
  • + 1
 @xeren: i actually don't even want a super stiff wheel. Overly stiff wheels being good for riding is a myth.
  • + 1
 @MTBrent: really? I'm sure you can do better, c'mon
  • + 5
 Chris king solution???
  • + 3
 Right, nobody will, unfortunately.
  • + 8
 People with the money for CK hubs would rather just buy new hubs/wheelsets, Knowing their hubs are "adapted" may be too much to bear. Plus, they're going to NEED the extra "stiffness" they sense is lacking without Boost.

I speak only the truth. Now if your CK hubs are USED... it might be a different story.
  • + 3
 Two weeks.
  • + 1
 Yes plz.

Talked to CK about it, they want me to buy an $80 axle and re-dish the wheel 5mm. So basically just buy a new hub, that's what i heard.
  • + 1
 Buy a new hub - I spoke to them yesterday Frown

I'm having a 10mm spacer made for the drive side and will just have the wheel dished
  • + 1
 @lockwood: better to go 5mm each side and a disc spacer surely? They are available on eBay for less than £20
  • + 4
 I have two sets of king wheels. I'm not so happy with Boost.
  • + 2
 @Racer951: That's what I used on my front CK hub. Use 1" heat shrink tubing to hold the spacers in place.
  • + 1
 i've know a few who just went to a machine shop to make their own king boost adapters front and rear
  • + 1
 @lockwood: Just get a cheaper hub from another brand. It probably will be as good with less drag. "King hubs have a bit of a break-in period. Though the axles are adjustable, we found ours to either be too tight or too loose during the entirety of the test. Brad Walton,
Pinkbike, Jan 9, 2013"
  • + 1
 I'm a chris king homer, so until they make something I will be stuck on one certain wheel set
  • + 1
 @PinkyScar: lmfao! Too funny
  • + 2
 20mm front, 150mm rear.......Fixed it
  • + 1
 Please MRP, let design a Boost Adapter for Centerlock front hub (most of DT Swiss wheelset are Centerlock)
  • + 1
 The boost adapters work for DT Swiss hubs, but only if you have the press in end caps.
  • + 1
 We have another kit for DT 240os hubs with the large, threaded end caps.
  • + 1
 The ramp control is providing something like a progressive HSC adjustment????
  • + 0
 110mm wider fork doesn't make a difference ?
  • + 1
 Just make it black
  • + 0
 MRP, no re-dishing and no spacer kit for 142mm rear wheel please!
  • + 3
 Something tells me you shouldn't use a boost adapter on the cassette side because it will mess up your chainline...
  • + 1
 Exactly, you can't center the rear wheel without moving the cassette further inboard, messing with chainline. I've run 142 wheels in 148 dropouts without redishing and was surprised out how little it made a difference, a big tire is just a tad closer to non-drive side chainstay, but smaller tires are fine.
  • - 2
 i dont really see the big difference between the mrp ramp control and compression dampening
  • + 1
 Damping is (generally) linear- it slows at the same rate throughout the travel. Air, being compressible, while fluid is not, means that as the air tries to cram into the orifice, it compresses, and provides more bottom out resistance and a progressive element to the spring.
  • - 13
flag WAKIdesigns (Sep 19, 2017 at 11:08) (Below Threshold)
 @therealtylerdurden: quite frankly I have no fkng clue how it works, how would pressure within the air spring and inside the ramp up cartridge not equalize after each cycle. It's easier for me to explain how Jesus walked on water
  • + 19
 @WAKIdesigns: well now i am curious. how did jesus walk on water?
  • + 4
 damping absorbs energy, springs store energy.
  • + 2
 @adrennan: Crocs.
  • + 3
 @adrennan: here is a HD rebull gopro movie of jesus walking on water
www.youtube.com/watch?v=Tw-sAUSmkfk
  • + 0
 @scottzg: i guess my confusion is they describe this as speed sensitive which is generally what dampening is. i dont see how this makes the fork more progressive. progressive implies as there is more displacement, more force is required to generate more displacement. not sure why an honest question is getting neg propped.
  • - 2
 I saw Cirque Du Soleil in Las Vegas. They also walked on water. I think they used thick glass panels a few inches under the water...maybe Jesus used a similar technology? @adrennan:
  • + 1
 @adrennan this has nothing to do with dampening. this is to modify the spring characteristics.
You can change the volume of ramp control by turning the dail. the cartridge can occupy more or less space inside the air chamber and hence change the spring characteristic in exactly the same way spacers would but without the need to disassemble your fork every time you want to change or try a different setup.

dampening is basically how much of the impact energy is converted into friction (heat by pushing oil through valves)
A spring by itself would basically kick back with the same force the trail pushes into it hence you would bounce around like on a pogo stick. by changing the rate or the characteristics you can change how much force is needed to push it for a certain distance.
Dampening means to absorb the impact energy (or correct transform kinetic energy into heat) which means it when the spring is compressed there is less energy stored in it and it will not kick back like a pogo stick or a trampoline and your ride will feel smoother...
  • + 1
 @michibretz: the article pretty clearly says that this is not the same as spacers; going so far as to say the cartridge is speed sensitive vs spacers being position sensitive. a spring curve that changes based on speed that it is compressed is not the same as changing based on position.

lets take an example (i am using easy numbers for my sanity). using the ramp control, it is my understanding that the first 2 inches of your travel would be firmer off of a 6 foot drop vs a 3 foot drrop. without the ramp control and using volume spacers instead, the first two inches of travel should feel roughly the same of the two different height drops.

this is just how i am reading the article. but it sounds like your entire stroke would get firmer off larger drops with the ramp control installed, not just the end stroke.
  • + 2
 @adrennan You're kind of right, but the Ramp Control Cartridge provides compression damping only when the fork is near the end of it's stroke. So when the fork is compressing more slowly the compression damping effect from the air passing into the Ramp Control Cartridge's air port is low (this would feel like having no bottomless tokens), then when the fork is compressing rapidly like from a massive drop the compression damping effect of the air flowing into the cartridge is much higher (this would feel like having a few bottomless tokens).

Basically it's compression damping on the flow of air into the Ramp Control Cartridge.
  • + 0
 @adrennan your understanding is mainly correct, michibretz is describing something else like an externally adjustable piston (which was explained in the article..., grrr). Although I'm not sure you'd notice a big difference in the "first two inches" as you say in your post - probably more in the mid-stroke as pressure really starts to build.

There *IS* some damping going on, however since it's a compressible fluid (air) instead of an incompressible fluid (oil) the characteristics will be quite different from any oil damper. I'm not sure if it would feel anything like "damping" as you think of it on a normal fork. With oil, fork travel always corresponds to a proportional amount of oil volume flow, because in an incompressible fluid pressure buildup is instant. With the MRP system, pressure builds up in the main chamber first, then leaks into the cartridge at a rate determined by your adjustment - so damping effects would be delayed and small, which is part of the reason we use bladders to keep air *out* of our dampers. This would almost be like changing the amount of air in your spring throughout the course of the compression, but it's hard to describe because it's not just a function of position, but time/speed as well. In practice *I think* this would result in a harder initial hit but more linear response overall, compared to volume tokens which are progressive. Again, I don't think the damping effect would be that noticeable, mainly because air is a shitty damping fluid. I think you'd mainly notice what it was doing to air pressure in the main chamber, but the two are related.

On the rebound stroke air would flow back into the main chamber, but since rebounds are generally way slower than compressions I'm not sure you'd notice any difference on rebound. The exact point at which the pressure would equalize would depend on your adjustment and the speed of the impact. If it's wide open it's basically equalized the whole time, if it's mostly closed off it may not equalize until the rebound stroke.

@WAKIdesigns it also allows you to ride across water!
  • + 3
 @adrennan: from your question it sounded like you're struggling with dampening vs. spring characteristics hence i tried to describe the difference.

Yes its not exactly the same as spacers.
I am not 100% sure how it exactly works even though i have one installed on my own lyrik. I did not open it up.
Reading the description my best guess is that the piston or slider inside the cartridge is not completely sealed (or having a tiny hole) which would result in air pressure behind it being the same as in front of it. if you have a have a high speed impact the air would have to travel behind that piston which will only happen with a delay hence the effect on high speed would be comparable to the effect of spacers. In a way this is very similar with oil getting pressed through a hole in a dampening cartridge however because of oil being a thickish fluid a lot of energy is used for achieving this displacement where as a gas can travel through the valves with much easier and will provide no significant energy loss or dampening.

on the other side If you press very slowly air pressure behind the piston can equalize through the small hole in time so you will not feel a difference to a regular fork without spacers.

you are right on the stroke. because s smaller volume air spring is more progressive the beginning of the stroke would not change much when you drop. towards the end of the stoke the spring becomes harder and harder which should keep you from bottoming out without sacrificing sensitivity in the beginning like simple higher air pressure (or preloading) would do

In my mind this would be the only way it would make sense to construct a cartridge like this. A closed chamber behind this piston would mean that you by reducing volume (making the fork more progressive) you would also raise the pressure inside the spring chamber which would make the spring harder but that's not is not the case.
The other good reason for assuming the cartridge is built like that is that it's fairly cheap and manufacturing a completely sealed piston like the air spring itself would be more complicated and therefore more expensive...
  • - 1
 @michibretz: i think i accept that answer. i understand the difference between dampening and spring rate. my questions related to this mechanism. it almost seems like it is halfway between altering dampening and spring rate.

maybe @NoahColorado can chime in on the mechanism?
  • - 1
 @adrennan: *damping. And you may think that you understand the difference... But you obviously don't.
  • + 0
 @therealtylerdurden: THANK YOU FOR YOUR GREAT CONTRIBUTION TO THE DISCUSSION!
  • - 1
 @adrennan: lol no problem. Thanks for yell-typing at me!
  • + 2
 @adrennan: "it almost seems like it is halfway between altering dampening and spring rate."

This is sort of correct. It's almost like if your token volume changed with the size (speed) of the compression. The damping of the airflow is what changes the "virtual" volume, but it will feel like different spring pressure, rather than like compression damping with oil.

FWIW, the PB article reviewing the cartridge has a pretty helpful graph and explanation.
  • - 4
flag WAKIdesigns (Sep 19, 2017 at 14:54) (Below Threshold)
 @adrennan: dudes woke up in the morning at the beach. Where's Jesus? Bugger was high as a fkng house yesterday talking his stuff again, probably sleeping in the boat. Hey Jesus! Pause... Aye! I'm coming. So the tide was down and as he approached them it looked like he can walk on water. It was shallow but in the morning with sun behind him, no wind. Simple... I believe he existed... he was really getting high on DMT and weed though... so were those 12 dudes... later it came out that Judas was working for wine lobby... so they pinned him. That's my theory, please let's don't ramp this up too much
  • + 1
 MRP ramp control is very simple. The stock Fox fork has a long tube connecting both chambers inside the air spring assembly. MRP device block that port at the negative chamber (the entire air rod must be remove). Inside of the cartridge is a seal surface that can move up or down to fill the space and make the job of the tokens. It can help to prevent diving under hard braking but if you let me choose over mrp device equipped forks or regular one´s whit compression dampening I choose compression control equipped forks all day long. MRP only changes the spring characteristics (linear or more ramp to the end of the stroke) compression a rebound controls the speed the forks react to the terrain.
  • + 1
 @adrennan: you can compress the air inside the fork till certain point, that is the basics of any air piston driven fork. When you put any tokens on your bike that curve is changing,yes but for the same amount of damping now you need less air cos the space to fill is smaller than before. If you put all the tokens inside of your forks and the same amount of air than when you ride 1 token is almost impossible to use all the travel of that forks. It can ruin your bike setup really quick if the rear end is not matching the forks setup. MRP=tokens, is the same thing,same basic,only difference is whit MRP device you can dial air volume whit clicks,no need to open the forks every time you need to change air volume and you can fine tune cos it has 15 positions not 4 or 5.
  • + 0
 Low tide and a sandbar
Below threshold threads are hidden

Post a Comment



Copyright © 2000 - 2019. Pinkbike.com. All rights reserved.
dv65 0.047464
Mobile Version of Website