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Box One 11-Speed Rear Derailleur

Average User Rating: (Good) Vital Rating: (Excellent)
 Box One 11-Speed Rear Derailleur  Box One 11-Speed Rear Derailleur  Box One 11-Speed Rear Derailleur  Box One 11-Speed Rear Derailleur
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Tested: Box One Drivetrain

Rating: Vital Review

The *big two* have gone pretty much unchallenged in mountain biking's derailleur and shifter game for years. Now Box Components is looking the change that with the launch of their Box One PushPush shifter and 11-speed rear derailleur. Box, who has a long history in BMX, took a slightly different approach (much like SRAM did when they first entered the market) when it comes to the typical action of a shifter. The One PushPush shifter features a single lever, as opposed to the traditional two-paddle system, which handles both upshifts and downshifts. This is made possible by a dual-motion design where the lever can be both pushed forward and inward. The rear derailleur has some unique features like a carbon fiber / nylon composite body as well, Box’s Pivot Tech spring-loaded cable stop, which they claim will reduce damage should you lay the bike over or snag a rock while riding. With a maximum tooth capacity of up to 46 (the common max for most 11-speed drivetrains) we were eager to slap the new drivetrain on our trail bike and get testing.


Box Components One Rear Derailleur Features

  • 11-Speed Specific
  • Carbon Fiber / Nylon Composite Body
  • 6061-T6 Aluminum Cage
  • Compatible with Box and Shimano 11-Speed Shifters
  • 9-46 Tooth Cassette Range
  • Matte and Gloss Black Finish
  • Weight: 265 Grams
  • Patent-Pending CamClutch Tech
  • Patent-Pending Pivot Tech
  • MSPR: $174.99 USD

Box Components PushPush Shifter Features

  • 11-Speed Specific
  • Cold Forged 6061-T6 Aluminum and Carbon Fiber / Nylon Composite Construction
  • Adjustable Clamp Allowing 10mm Left / Right Placement
  • Compatible with Box and Shimano 11-Speed Derailleurs
  • Up to 4 Downshifts at Once with Single Upshifts
  • Aluminum Clamp
  • Stainless Steel Zinc Oxide Coated Hardware
  • Matte and Gloss Black Finish
  • Weight: 120g (w/ Clamp)
  • MSRP: $74.99 USD


Initial Impressions

At a total weight of 385g for both the shifter and the derailleur, the Box One drivetrain runs an average of 42 grams heavier when compared to top 11-speed offerings from SRAM and Shimano. Box pricing hovers somewhere between Shimano’s XT and XTR groups and SRAM’s GX and X1 groups. The matte black finish and small orange graphics give them a subtle and stealth appearance, which is never a bad thing in our book. Installing the drivetrain was no different from any other drivetrain we’ve ever worked on, and everything went together as expected.


We paired up Box’s One drivetrain with the SRAM 11-speed 10-42 tooth cassette that was already on the bike. In the stand, shifting was excellent after dialing in the proper cable tension, though it did feel a bit awkward with the single lever design. Having made the switch between multiple shifters in the past, we know it usually takes a few rides to adjust to the new motions.

On The Trail

“A swing and a miss” is the best way to describe our maiden voyage with the Box drivetrain. Muscle memory had us fumbling around a bit when it came to our instinctual motion of going for a shift. Eventually, after concentrating on how to shift for a couple of laps, the motion became natural, and, for the most part, we never had a second thought about it.


In terms of gears per shift, the Box drivetrain is somewhat a hybrid between SRAM and Shimano, in that shifting into the higher gears is one-click-one-gear (like SRAM), and you can cover a four-gear spread while shifting into the lower gears with a full push forward of the paddle (like Shimano). Even on a wide, four-gear shift, the derailleur performed well: no gear wandering, rough shifting, or loud popping noises as long as we shifted properly.

We did drop our chain a couple times over the first month aboard the Box drivetrain, despite using a narrow/wide chainring, and opted to run an upper guide for the duration of the test. We did compare the clutch tension to the SRAM derailleur it replaced and noted that the Box One derailleur's clutch is not quite as forceful as SRAM's. Aside from that, the Box Components drivetrain provided reliable, crisp shifting which was pretty much set-and-forget for the remainder of our test.

Things That Could Be Improved

As we just mentioned, we compared the clutch of the Box One derailleur to SRAM'sand found it to be notably weaker. It's likely this is the culprit when it came to dropped chains. We opted to run a chainguidewith the Box drivetrain to help prevent further lost chains, and we'd say a stronger clutch is called for. We should also mention a compatibility issue we found. Halfway through our test, we received a 9-46t cassette which we installed on our test bike and found the Box One derailleur’s cage couldn’t handle the extended range offered by that tiny 9-tooth cog. The chain had to be cut too short for the derailleur to hold any chain tension while in the highest gear, yet still be long enough for the 46-tooth. While Box does state the minimum tooth count for the derailleur is 9 with the max being 46, an actual cassette with that specific range just didn't work on our experience. Likely a 10-46 tooth range would be fine, but the extreme spread of e*thirteen's TRSr 9-46 cassette was just too much.

Long Term Durability

While we’ve yet to lay the bike over or tag a sizable rock, we can say the Box One drivetrain remains quiet and still functions as well as it did on day one. No strange issues have popped up nor has the drivetrain given us any indication of premature failure. That said, we were unable to test the claims of the Pivot Tech system which prevents bent derailleur hangers and other damage. Time will tell if the system works and we'll update this article if and when the time comes.


What’s The Bottom Line?

One of the hardest parts of this test was searching for the answer of why Box Components designed the dual-motion shifter the way they did. Did we find that it offered a specific advantage over the competition? Not particularly. When SRAM released the dual-thumb triggers, the advantage was obvious: you no longer need to take your index finger off the brake lever to upshift. Shimano recognized that and answered with a similar system. Sure, with the Box system, the dual-thumb technique of shifting continues, it’s just…different. Is that alone enough to sell a product? In our opinion, no. Since they created a solid performer that we found competitive with the "big two" in terms of shifting, weight, and value, they should find some traction in the market. Kudo's to Box for thinking outside of, well, the box, and backing it up with a product that delivers. 

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About The Reviewer

Fred Robinson - Age: 32 // Years Riding MTB: 14 // Height: 6'1" (1.85m) // Weight: 240-pounds (108.9kg)

"Drop my heels and go." Fred has been on two wheels since he was two-years-old, is deceptively quick for a bigger guy, and likes steep, fast trails where he can hang it off the back of the bike. Several years of shop experience means he's not afraid to tinker. He's very particular when it comes to a bike's suspension performance and stiffness traits.

Long-Term Review Box One 11 speed Rear dérailleur

The Good:

It’s easier to clean the jockey wheels than on Shimano rear derailleurs, due to the more open design, the jockey wheels are more exposed & the lower is bigger. The cage swings very smoothly
You can fully take it apart, as the swing arms have E clips, so removing them is easy with a screwdriver, So far Box does not offer every single part as a replacement.

The Bad:

The spring tension is too high.
The Clutch is not adjustable, so when it wears you can't regain hte same performance, But the new version has adjustable clutch.

Overall Review:


Going from Xt m8000 with uncut 116 link Kmc x11 Sl silver chain, I had to add 5 links, due to the bigger tension pulley, but with 34T Oval I could use stock chain length. But if I were to use 32T or smaller I don’t Think it would be an issue, but I haven’t tested this.

Unlike the other current options, Box One has bushings, which is great, bushings can be replaced, which is very easy to do, the rear derailleur can be fully assembled, the only thing you need is a screwdriver to remove the E clips. I wish all Rear derailleurs fully serviceable.

But the Top pulley is also more exposed, and easier to clean than on Shimano.

Muddy Fuel ex 7 29nr2_0587White Lightning Clean Ride_5734

PhotoFrom this side, you can see the E clips,

BOX ONE 11 Speed rear deraileur_0396PhotoPhotoWhen adjusting The Limit screws I recommend using smaller separate Allen keys instead of a big Multi-tool, as the Pivot Tech Swingarm is partially covering the limit bolt, So you will scratch the paint off pretty fast.


I have had the chance to smash it, on this technical section this was the result : so far it seems to be ok, can handle some scrapes
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the composite got bit scratched and the big bolt too, but no real damage was done, , it worked as before, but had to adjust the limit bolts, the composite part replaceable, but not seen it offered as a spare yet.

Box one scratched_2120
BOX One 11 Speed RD_0215_DxOMuc Off Dry lube_3224
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Shifting performance:

The rd moves easiest up from the the highest gear/smallest cog, at the second smallest cog it the resistance can be felt, it gets worse and worse the bigger the cog.

I noticed there was a difference in how stiff the springs were between the two Box One rd's I got, one still has a stiff spring.
I prefer Shimano trigger shifter, So I use the XTR m9000, it seemed like a good combo, but the stiff spring is way too fatiguing.

The shifting is very smooth, it's actually smoother than Shimano XT M8000, because of the cam clutch, it gets stiffer as the lower gear you use, but this makes the high gear as there is no clutch at all, this is probably also due to the initial movement where the clutch does not seem to engage, but this won't be an issue unless you ride like a madman within the top gear, so any issues are unlikely, But I read reviews saying they dropped the chain, but some of them did not use chain guides.

It gets stiffer as the lower gear you use, but this but in the smaller cog if feels lighter, due to less resistance. But this won't happen with normal riding, so any issues are unlikely, But I read reviews saying they dropped the chain, but some of them did not use chain guides. I guess the chain could drop if back-pedalling downhill in max gear, which no one normally does, or even on the flat you will feel the chain slap. I rode pretty hard and fast in technical sections and I never had any issues, but eventually it was a problem, when the bushings wore out there was so much play that it created more slack in the chain probably causing the chain suck i got On my fuel ex, But this happen before too, but that was due to the cassette being worn I think, but maybe it already started back then summer 2018, but that issue was gone when I swapped back to the XT cassette so it probably was not, but the issue came back after using the Xt cassette for a while, but the cassette was significantly more worn, and the Box One Rd has a lot more slack and sag, The initial play of the clutch is also a contributor I think, and both combined were causing problems, but just the slack chain alone would be causing issues, when shifting it had issues both ways so I think it was march when I swapped back to the XT rear dérailleur, and later I swapped back to Sun Race cassette, which I will run until I get a new Rd, I think it will be the next Box One.

In this video you can see how the bushing wear is on a Rd used month, few weeks, few days.

You can see the chain is slacker, and the Rd is sagging, I did not dare to use the Rd with the bolt the right way because I was afraid of ruining it, so I did what I did on the Fuel Ex, but this does not allow me to adjust the B bolt for the wear in the bushings to remove the slack, so I would have to do that or shorten the chain.

The spring tension is too high.


The Box One Rear dérailleur has a harder spring, which increases the fatigue I get from shifting, which already was pretty bad Shimano XT M8000 rear dérailleur

The clutch was quite harsh/ stiff in the start, but it eventually wore down, so the gets weaker than the Xt M8000 clutch can be.

I noticed the downshifts were smoother with the Box one, but this might be do to the worn clutch and heavier spring.
The lack of adjustment is a big flaw, but this is resolved with the new generation of Box One, it has completely new internally adjustable clutch.But I haven't found out if the spring has gotten lighter on the new generation, but it won't matter anyway if I get Archer components DX1 electronic shifting system, which I think I will need, because I fatigue my hands by shifting.

The Spring tension is so strong is actually abusing my thumb significantly more than the XT M8000 RD would, to the point in the tip of my thumb like a needle, if I do too much shifting, it can take days before my thumb is back to normal.

Last time it took 10 days before the pain was gone, also I had to use a lot of hand cream, the skin was wearing off at the tip of my thumb at faster rate in the winter and spring, due to dryer skin, of course having hand cream helps, but I forgot to apply it before riding, but I have been doing since that day again, but there is no cure for the pain I get when riding for 4 hours and shifting a lot, the rides after this ride I had to minimize my shifting to bare minimum, to avoid pain, only shifted when absolutely necessary, but if riding in a place that requires a lot of shifting, like I do at & to Skansehytta in Askim, and ride for 4 hours it's I will get pain for sure, but then rest of my body will be tired too, if I ride fast or do a lot of technical stuff, but it's always the thumb that fatigues first, even with rides I do less with my whole body as long as I have to shift a lot I get pain, so it can happen on even shorter rides.

So mechanical trigger shifter especially with activated clutch on the rear derailleur is not great for me, to abusive, especially with so strong spring tension, even with days or weeks of using hand cream and my skin is being normal, after several hours, my skin gets some wear, and pain, on not as long rides, but for the longer rides I get a longer lasting and more painful experience, but with XT RD it was much it happens at a much slower rate, and not as painful.

The B Screw & threads in the body for B screw failed, it's most likely due to alloy used, the next version comes with Forged alloy parts, so it should be more robust, it's promising.

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At first glance, I thought I had to adjust the B screw, But a few seconds later noticed that the screw has chewed off the edge of the hanger. Since then, I fully unscrewed it I discovered the threads were ruined, But then I discovered the B screw was switching between light and hard to turn as I unscrewed it, this was caused by the threads in hte body being completely destroyed. So I  put Xt M8000 on the bike.

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Rhis Rd is not really compatible with Trek rear dérailleur hangers, I haven't tested it on other brands.Box One_5057Box One_5059Box One_5062Box One_5063Box One_5055I hope the new Box One Rd will be strong enough for the threads to not fail, Also I hope other hangers on other bikes I want won't have a shape that cases the bolt to not sit properly against it, the Trek hangers sure don't work with this RD, but does with Shimano And Sram, I don't know if the New RD has changed the position or angle of the bolt

BOX One KMC X11 SL Rock n Roll Gold lube_5029White Lightning Clean Ride_5789White Lightning Clean Ride_5774

The position of the B screw does not help, I am quite sure it's the reason the hanger got so damaged, but maybe the hanger on my bike should be thicker where the B screw is, but I think the B screw position is not optimal, and the combination of the placement & not using forged alloy resulted in failure. but using the rear dérailleur with upside down B screw with nuts for extra support, seems to work well, I haven't had the issue on the other Rd. for Shimano Xt 11-46T I used one nut, for Sun Race 11-46T I used two nuts.

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Dislocating cam clutch spring, the spring wears out and becomes too big, and creeps out on both sides of the O ring until most of it pops out.
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This is the cam clutch, the big O-ring comes on top of the spring between the gap.
Grass Stuck in Pulley_4375
The jockey wheels can got grass stuck to it.

Grass Stuck in Pulley_4377Grass Stuck in Pulley_4384Grass Stuck in Pulley_4399Box One loose bolt_2028
I don't know why, but the bolt got loose, so I cleaned it and put Loctite 243 and it held on.
Box One loose bolt_2024



Some pics of the RD that did not fail:

The threads did not fail on this Rd, I know the body is not strong enough as I have seen failures by other users on Instagram, this one did not have any issues yet, but I reversed the B bolt and added nuts from reflectors for support, it has not failed the few weeks I used it a lot.
Box One_2852
Box One_2848
White Lightning Clean ride _20180927_113525
White Lightning Clean Ride_5734KMC chainlube dry ride_3646
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White Lightning Clean Ride_5741
Muc Off Wet lube 28.08.2018_5135white lightning clean ride_4356Box One cam clutch _0015How new RD looks like inside.

White Lightning Clean Ride_4335white lightning clean ride_4329Box One_2848


There is definitely potential, Box has some great ideas, for example, use of bushings, but there some flaw that can't be ignored.
BOX one has great potential, but the current rear dérailleur should not have been released to the public, as the product has major flaws, I hope these issues are fixed in the new generation of Box One.

So I can't recommend the First generation of Box one Rd at this stage, but I can't really recommend any other mechanical rear dérailleur or shifter either, I really hope they will fix this issue, by offering a free rear body upgrade, which would be easy to do, & easy for the more custom to install, as the Box ONE Rd can be fully disassembled, with only a screwdriver & Allen keys.I recommend keeping up to date with Box is doing.

Original review:

Box One transmission

The Good:

Working crisp so far

The Bad:

Waiting on the short cage version for the DH bike application - the wait, if that's bad. :)

Overall Review:

Just want to comment on the Box's rear der integration with the e13 TRS 9t cog's. I too had an initial issue with tuning the Box shifting with my TRS cassette in the 9t cog.

Otherwise, on a standard cassette with either a 10 or 11t cog, it's great.

The trick for me was a combo of getting just the right chain tension derived from cutting the chain length just to the absolute minimum length and fiddling with the B tension adjustment. 

It's been running smooth and good on my Intense Spider275c with e13 TRSr 9-46 cassette. 

I'm building up the new Tracer so I'm hoping for the same success I had with the Spider. 


Product Box One 11-Speed Rear Derailleur
Riding Type Trail
Speeds 11-Speed
Clutch Yes
Cage Length Long
Weight 0 lb 9.3 oz (265 g)
Miscellaneous Cage Material: Aluminum
Body Material: Carbon fiber // Nylon Composite
Spring: Steel
Finish: Matte and Gloss Black
Colors: Black w/ Chrome and Orange Highlights
Mount Options: Traditional Frame Mount
Compatibility: Box and Shimano
Minimum Cog: 9
Maximum Cog: 46
Technology Highlights: Patent-pending CamClutch, Patent-pending Pivot Tech
Price $174.99
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