Pinkbike Poll: Are Rear Derailleurs Reliable?
Just mentioning the word 'gearbox' is enough to make certain mountain bikers start salivating, their heads full of dreams about a rear derailleur-free existence. Unfortunately, despite a number of valiant efforts, gearboxes aren't going to be the norm anytime soon, which means the vast majority of us are riding through the woods with a derailleur that hangs a few inches above the ground, a position that almost begs for an encounter with a rock or other obstacle.
Despite how vulnerable they seem, I'm constantly amazed by the amount of abuse a rear derailleur can take and still keep on shifting. In fact – knock on wood – I can't even remember the last time I tore one clean off a frame. As much as I'd like to credit that fact to my riding skills, I've had too many hard crashes over the last few years for that to be the case. More than likely, it's due to the subtle-but-effective revisions that derailleurs have undergone. It doesn't matter whether you're talking about Shimano or SRAM – both company's derailleurs are now tucked closer to a bike's frame and cassette, making them much less likely to catch on an obstacle.
![SRAM GX Review]()
![Shimano XT M8000]()
SRAM and Shimano have both taken steps over the last few years to tuck their derailleurs closer into the frame.
There's also the fact that replaceable derailleur hangers are now the norm, and in most cases the hanger will fail or bend before your derailleur does. For that reason, it's not a bad idea to keep a spare hanger in your pack, just in case a pesky branch or rock decides to smash into your bike and try to end your ride.
I may be enjoying a lucky streak when it comes to rear derailleurs, but what do you think? Are you satisfied with the performance of your rear derailleur? Is there room for improvement? Cast your vote below.
Despite how vulnerable they seem, I'm constantly amazed by the amount of abuse a rear derailleur can take and still keep on shifting. In fact – knock on wood – I can't even remember the last time I tore one clean off a frame. As much as I'd like to credit that fact to my riding skills, I've had too many hard crashes over the last few years for that to be the case. More than likely, it's due to the subtle-but-effective revisions that derailleurs have undergone. It doesn't matter whether you're talking about Shimano or SRAM – both company's derailleurs are now tucked closer to a bike's frame and cassette, making them much less likely to catch on an obstacle.
There's also the fact that replaceable derailleur hangers are now the norm, and in most cases the hanger will fail or bend before your derailleur does. For that reason, it's not a bad idea to keep a spare hanger in your pack, just in case a pesky branch or rock decides to smash into your bike and try to end your ride.
I may be enjoying a lucky streak when it comes to rear derailleurs, but what do you think? Are you satisfied with the performance of your rear derailleur? Is there room for improvement? Cast your vote below.
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NB: Sorry for the lack of clarity, I am working my way through 20L of session ale. :cheers:
But to clarify on one of the questions, I've never broken a derailleur but I've definitely busted up more than a few hangars.
BTW @pinkrobe , sounds like a session.
The only 2 downsides will be increased mass, in place where it least matters, and eventual issues with frame mounting, however giving it a bit of thought I think that if so many E-bikes from various companies can use one type of engine(not to mention countless different models of city bikes where manufacturing costs are waaay more concerned) there can easily be a standard for mounting gearboxes. Price argument is out of the window, considering how much XTR Di2 costs.
...Which is a silly argument anyway, I barely need the spread of a 11-42, personally. Even the first look for the Eagle stuff Kazimer said he didn't think he needed to move up the 500% on at least one of his bikes.
As for the drag, as @WAKIdesigns is trying to point out, numbers don't tell the whole story. Is there more drag than a derailleur system? yes. just like a chain has more drag than a belt drive. But at the same time, a 315HP car has more power than a 314HP one, but I defy you to be able to tell the difference in a blind test. & that's apples to apples, derailluers vs gearboxes is harder to quantify, because they have different advantages to each other.
Basically, it comes down to: are all the disadvantages of derailleurs worth the reduced drag? I know I couldn't tell without a long period of owning both, but gearboxes seem to really only have weight & drag against them, so it would have to be REALLY bad to convince me to stick with derailleurs.
FWIW, switching gears mid-climb is easier with a gearbox than a derailleur. I haven't had a skip or drop shifting on a climb in ages, but at the same time, if I think about what I'm doing, I change my pedaling slightly during the shift. that wouldn't be necessary with a gearbox. Also, that lag between shifting & the chain moving up disappears.
@Rubberelli - "why haven't they done it yet" is not an argument sorry
We're getting there.
But I will be ordering in the zerode taniwha when it's released not because it I'm scared of destroying a derailleur but pretty much every other reason..
Quick search on google and I picked up a X9 for £66.
Having now switched to Zee I pay about £30 for mechs!!!
I would rather have a decent shifter as that's ultimately what controls the mech and if that's not working properly your mech won't function smoothly. Oh and new cables and outers every year or sooner
Don't get me wrong: external drive on MTB bike is way off from being perfect but it's reliable, efficient, easy to maintain and CHEAP. I do believe in MTB gearboxes but I can bet you any money that they won't be popular enough to get cheap sooner then next 10 years.
Companies have tried gearboxes the same way they are trying e-bikes, little by little, but there's a reason why e-bikes lifted off and gearboxes haven't.
At the time, 'LX was second from the top(XT), and had the same internals(IIRC) just with heavier casting
That was the first and last time(knock on wood) I did any damage to a derailleur, outside of breaking the hanger-which is meant to do so.
If I'd be in the market for one of those premium drivetrains, I'd probably prefer a gearbox. At least I'd not be investing in expensive stuff that would soon wear out. But for the lower segment where you already get steel rings and sprockets that won't wear too soon anyway, there isn't really a viable alternative from the gearbox camp. Which is a shame really. If it so expensive to develop something new, just get a Shimano Nexus 7sp hub in the frame. If these are sold on 700 euro commuter bikes, they should never add 2000 euros to a mountainbike like the effi or pinion option does. 200 euros at most and it would definitely be worth it.
Dunno, I'm not convinced. Yet.
Back 50-100 years ago when xc derailleurs were used on dh bikes, I would go through 4+ XTR derailleurs in one season.
Lesson learned: always bring my Topeak Hexus II Multi-tool and a couple beers on a ride.
Also, there seem to be no "short travel" Pinion bikes at the moment unless you custom order a Nicolai.
Oh
Shame they don't make them anymore : (
I also like the really wide pivot linkage on the upper knuckle on the saints. 4 seasons of pretty hard DH and no slop yet!
www.pinkbike.com/forum/listcomments/?threadid=148662&pagenum=1
Nine4life! (...or maybe 8 )
As for the hanger mechanism, the older m810 is MUCH beefier than the newer zee models. See the photos below:
www.bikemag.com/files/2011/01/wpid-Saint_M810_drlr.jpg
p.vitalmtb.com/photos/products/11768/photos/10691/s780_2013_Shimano_Zee_shadow_plus_rear_derailleur01.jpg?1360799076
I agree, the newer ones are flimsy and I'm not a big fan, but the one I have is borderline indestructable! The cage will bend long before that hanger will! (I've already had to bend the lower cage back into shape a few times)
Boxes are the next logical step you loose 1LBS or more off the back wheel so it makes the suspension work better. Also it eliminates the rear derailure from having any effects on the suspension system. The difference in efficiency is there but getting smaller. Since Gwin won a WC DH race with no chain does that really matter in the DH world? The 1.5LBS or so you gain is lame but over the next 5 years I would not be surprised to see the boxes loose 300-400 grams.
The cassettes we have today are incredible bits of machining, and you can get a SRAM GX for $100. So there's performance available at pretty much every price point. There's no chance of a gearbox matching that and, as someone who's worked on transmissions, the complexity is going to f*ck everything up. The great part about bikes is pretty much anyone with any mechanical aptitude can work on them, throw a gearbox in the mix and you're taking it to a mechanic for every shifting issue. There's a reason the hammerschmidt died a silent death and that Nicolai are boutique bikes you rarely see. I'd take improvements in wheel strength, brakes, tires, and a lighter overall bike over gearboxes any day in terms of beneficial advancements. Even a perfect gearbox is just a marginal gain with too much sacrifice.