When SRAM first announced their Universal Derailleur Hanger
(UDH), it was touted as a way to ensure that finding a replacement would be an easy and relatively inexpensive task. It turns out there might be more to the story, at least based on a patent that was
recently granted to SRAM's German division with the catchy title of 'Drive arrangement for a bicycle.'
The patent language describes what sounds like a fairly typical drivetrain, but the illustrations make it clear that there are difference between this derailleur design and SRAM's current offerings. The derailleur uses a direct mount design, and the body is tucked much further underneath the chainstay compared to what's currently the norm.
It appears that if a frame was designed to use a UDH, then it would be compatible with this new derailleur. In other words, the UDH acted as a benevolent Trojan horse, bringing inexpensive replacement hangers to consumers while also opening the door other mounting possibilities, which seems like a smart way to introduce a new standard.
It should be noted that the first patent applications for this design were submitted back in 2018, and the patent was granted in April of 2021, so some of the illustrations seen here may be familiar. Shimano also deserves a nod for introducing a direct mount derailleur
back in 2012, although that didn't really change the orientation of the derailleur in relation to the frame, and it also never really caught on.
According to the background portion of the patent, “A rear derailleur configured for greater stiffness may omit an intentionally weak mount. In this configuration, it may be beneficial to locate the rear derailleur at a relatively inboard position so as to protect the rear derailleur and frame in the event of an impact.” As the gear range of cassettes has grown wider, derailleur cages have grown longer, which means they're more exposed to potential impacts. It looks like this design could potentially allow for a shorter cage derailleur, or at the very least help keep it out of harm's way. In addition, an overall stiffer rear derailleur would help with shifting performance, a benefit when you're dealing with a 10-54 tooth 12-speed cassette.
The new derailleur design also seems to do away with the conventional B-tension screw, the one that can sometimes back out and throw a derailleur out of adjustment. According to the patent, the positioning will still be adjustable during installation, but once the derailleur is in place it's designed to stay in that orientation. “The rear gear changer has at least an adjustment state and an installed state. In the adjustment state, the gear changer mounting unit is not fully secured and may be rotationally adjusted about the rear axis. This adjustment state may be used to rotationally align the rear gear changer for proper tension of the chain.”
The patent also includes detailed description about how the chain will interact with the front chainring and cassette, although nothing stands out as being
that different from the methods SRAM currently employs. However, when (or if) this drivetrain moves from concept to reality it wouldn't be surprising to see it include features designed to improve its ability to shift under power.
Will we see this new derailleur in the real world any time soon? That's a good question - so far we haven't seen anything in the wild, and SRAM's response was 'no comment,' but with racing starting to ramp up we'll be keeping a close eye on SRAM's athletes to see if they're running anything out of the ordinary.
235 Comments
But, it this is actually a better mousetrap, there will be only one choice. Seems like a rare combination of brilliant marketing and engineering, in concert vs. covering for one another.
Nicely played, SRAM.
wheelbased.com/2021/04/08/rear-gearshift-mechanism-for-coaxial-installation-by-sram
This was a sly move by SRAM to push into a position where product managers who are on the fence regarding specification on certain models, will most likely lean towards SRAM simply on price.
Customers may finally have a better shifting SRAM bike, but in doing so, all bikes will be a bit more expensive.
The only real world benefit would be if this actually catches on, is that finding a new hanger at some random shop will be much easier, and that is indeed a win, but it could have been done without the slimy business practices.
I think its a shit way of doing business. You are either technically better, have a better price, or you are SRAM.
I don’t really see how it’s a slimy business practice - the UDH makes a ton of sense, especially if you’ve ever struggled to find a replacement derailleur hanger for a bike without a dealer in your area. It works with all brands of derailleur, and if implementing it also allows for new derailleur designs in the future that seems like a benefit to me.
If the suggestion is that it's 'slimy' for SRAM to innovate in ways that may decrease the price of their products vs Shimano, and that they should in some way do Shimano a favour by keeping parity on price, then that's just insane. If what they are doing is as you describe then it's 'good' business, and will hopefully get Shimano to respond by innovating and/or lowering the prices on their products - that way we can all have better products for less money, it's the way it's always gone.
New ideas are not all ways better from company that thought 29.999 was good?
I bang my hangar, and after placing a new one (i allways carry one), tge RD X01, was bent/twisted.
Question: on the trail, if I bend or brake the RD, and not the Hangar, I'll need a) UDH hangar, and b) Rear Derailleur, correct?
With the current design of derailleur hanger, the pivot that the derailleur swings around under impact (the main mounting bolt) is pretty close to being in-line with the front of the derailleur, so an impact to the front (like hitting a rock) has a relatively short lever arm to move the derailleur out of the way. As a result a lot of the impact will go into the derailleur and hanger.
With this new design, the pivot point is significantly higher up, so an impact to the front of the derailleur can swing it under the pivot more easily, this should mean less energy being transmitted into the parts and instead that energy working to accelerate the derailleur out of the way. (which should be relatively harmless).
Ideally anyone can make a UDH so sram pricing on it is irrelevant, and makes finding spares super easy.
In two years .
Broken 3 derailleurs . Broken 0 hangers .
Hell check out the drop outs on a Banshee or RSD for that matter.
And a little plastic gauge you have to bring with you, to confirm proper setup.
4.bp.blogspot.com/-sKyrXRBpGD8/V78Pu-gVN2I/AAAAAAAAKuY/5RwnI2DxsEACbFN9-CQQ4UfqYtFhg3eFQCLcB/s1600/93%2Bschwinn%2Bcrisscross.jpg
I am old.
m.pinkbike.com/news/sram--universal-derailleur-hanger-udh-eurobike-2019.html
And I Quote "I think most of you are missing the higher picture. The standard mount for a derailleur is quite antiquated. Imagine if companies world wide got on board with a new hanger design. This opens opportunities to improve the derailleur system. Currently there are limitations to this. B tension plates snapping, the flopping back and forth of the whole derailleur on the B tension. TRP has the hall lock which essentially locks the derailleur forward. I see this as the next step in bettering the drivetrain. This is definitely not geared towards unifying the industry standard in order to bring ease to the consumer. Proprietary is great for big companies like SRAM, it helps them keep market shares, and forces other companies to up their game. I for one am on board, but not for simplicity, or ease... But for innovation and improvement."...
Just sayin'
You would not want yor chainstay to break @juansevo:
If you suggest a carbon fibre mech hanger to pinkbike to ensure it is sacrificial you will be burned at the stake.
In fact, I can only remember one time the hanger broke and the derailleur was OK. But I’ve replaced lots of broken derailleurs over the years.
I've had plenty of bent hangers and that is a sign they are doing their job- saving the RD.
Remove the easily bendable part and what breaks instead?- you got it the RD.
They even mention they tuck it further in to protect it.
"A rear derailleur configured for greater stiffness may omit an intentionally weak mount. In this configuration, it may be beneficial to locate the rear derailleur at a relatively inboard position so as to protect the rear derailleur and frame in the event of an impact."
Obviously it never really caught on; it’ll be interesting at least to see what SRAM come up with..
www.mbr.co.uk/reviews/products/shimano-hone-rear-derailleur-44-95
If I rode my bikes with my daughters, I wouldn't need:
1) a new FS bike... no need! My 1986 mtb would be more than enough
2) I would need to change tyres every 10 or 15 years, after all those cracks appear!
Reality?
One Magic Mary lasted less than 50km, due to a rock that just cutted the side wall like a butcher!
Derailleurs? It depends on the luck! But in my worts year, had to replace at least 2 times.
So... it doesn't matter really on kms, or failleurs you have.
As general thumb rule, equipment will fail from all sorts of ocassions.
Being hard to find a replacement is for me a No-No.
When they start, they will present themselves as the perfect inventors / designers / engineers! Just LOL!
www.pinkbike.com/news/shimano-gearbox-in-the-works-files-patents-on-hybrid-roller-chain-sequential-shifting-transmission.html
But there are a bunch of details to solve on a new system. And as everyone knows, Shimano needs a decade before going in production. Maybe a smaller company is still quicker with a bit less refined product, but honestly I see this concept as the most feasable in the upcoming years
Thanks for the response!
The article was on 8 / 10 / 2019 !
I think if they were really interested we would have a lot more of them!
I think it just suits them to evolve the existing system piece by piece, taking advantage of us as consumers!
I hope to be understood !?
Right now, the currents drivetrains are actually really efficient, that is a required quality for a human powered vehicle, so it makes sense to keep it that way. In some case where efficiency isn't as critical, gearboxes are coming. E-bikes (valeo motor+box), cargo bikes, downhill bikes,... there will be probably more gearboxes in some precise categories of bikes than derailleurs. But not everywhere. XC/road/enduro bikes, and so on, will always benefit from efficiency much more than anything else.
Do you want to tell me that in the year of 2021 and with so much technology that we hold even in our hands, that they can't upgrade/develop further on this sector !?
I think/believe they just prefer to have us as loyal customers!
I think it's much reliable and much better behave having all this mass, in its center !
I think we see it from a completely different angle!
Thanks, anyway !
I respect the opinions of all of you!
But let me have my own!
It is about 90% the exploitation of the consumer and his pocket,
and a small 10% percentage of the type
"where to make all these changes in the process of the industry, leave them as they are"!
Thank you all very much!
Rohloff hub is generally within 1% of the efficiency of derailleurs, because planetary gearsets allow minimal gears with the effective gear being determine which combination you use.
One can also make a system that at its core has a 3 speed planetary gearbox through the cranks, which i turn drives 3 short chains linked to 3 different size cogs, and use a clutch based mechanism to select which cog gets linked to the output shaft.
The dawn of $15000 ebikes is making the astronomical costs were seeing, a bit desensitizing, and thus from a cost perspective and the more mainstream we're seeing 3D printing results look more and more positive, this is also an area weight is controllable without sacrificing strength.
I do believe we're on the verge of feasably making gearboxes at a competitive price, and be precise enough to properly negate any excess friction. Only time will tell, but what dictates acceptable cost on the market dictates the innovation timline...
That being said, the current iteration of the drivetrain is quite reliable, user friendly, and rather durable. Adding in Sram's warranty which is part of what you pay for when you purchase their products.
@iamamodel: I did this benchmark about a year ago and Rohloff is very far away from the other competitors. And lifetime of a product doesn´t interest you when you´re hitting a trail with your buddy and he´s 2timer faster cause you are running a extra kg on your back wheel. A compeatable product needs exacly, that it´s just better than a external drivetrain on the first ride
But had that in 1920s
But do keep hearing that people want a gearbox & wonder why no one else sees this solution?
Maybe no one else tends to ride overgrown trials trails
(seriously, how is this not a more well known and discussed issue, i've seen it happen to dozens of bikes!)
So no you cant have sealed drive!
worldwide.espacenet.com/publicationDetails/biblio?CC=GB&NR=2434565&KC=&FT=E&locale=en_EP
FTA: "The big questions here is: does the bike dropout need to be a standard for this to work?"
PB generally "Dont want more proprietary stuff"
PB when sram has a new part out "Buy this its the shit"
Anyway so far standards that sram brought that are quite nice:
- match maker
- UDH
- boost ( yep it Caspian at the begining, however now majority pf the frame and forks accept and old standard easily convertible )
- DUB
- Direct Mount
- 1x12 (that is cross compatible across all range (including Shimano)
- XD (everyone forgotten CB Shimano hubs that allowed smaller sprocket)
not so:
- torque caps
- boost for those who cannot ditch old wheel-sets or on CC hubs
- 28.99 mm ????? can you EVER forgive that marketing campaign
- 2 foot breaker bar on an 8 mm allen key to remove your crank
- bearings that seem to wear out after 3 months of low power fat ass pedaling
- google "Hambini DUB" for the rest of the drubbing..................
You just need to move it down BELOW "NOT SO" but it is clear SRAM has done way more good than bad.
That’s hilarious and sad to hear that I’m not the only one. Literally today I purchased an air impact wrench and a 8mm hex driver to try to get mine out. We will see how that goes.
Dub bearings wearing out after 3 months is flat earth like delusional bullshit.
I have lot's of riders in my group that are already past 2 years without problems
You should stop taking that ever ranting Youtube BB salesman wisdom for granted.
That's what I thought.
As for Hambini. I wish he would behave a little better but there is lots of good engineering in there. DUB is not that great. It’s not so much the 3 months but the fact that changing it out is a pain.
right, name a few?
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