Innovation of the Year Winner
2021's Innovation of the Year nominees
include RockShox' suspension-controlling Flight Attendant, the Digit Datum with its novel suspension design, the latest long-range ebikes and a product that promises to minimise the disadvantages of air suspension. But this year's winner is the brainchild of a young Canadian engineer that could save a lot of mechanical maladies.
The derailleur is possibly the best and worst idea in mountain biking. We all know that derailleurs suck. They're expensive, fragile and finicky, yet highly exposed to impacts from stumps and stones. But in a way, they're a really elegant solution.
The derailleur not only selects the sprocket, but its cage also takes up the spare chain when you shift to a smaller sprocket. This tensioning function is a gift to full-suspension bikes as it can also spool out more chain when the suspension compresses and the hub moves further away from the bottom bracket. And because you need a chain anyway to transmit the drive from the crank to the wheel, it's more efficient to use the chain as part of the shifting mechanism, rather than having a separate gearbox plus a chain connecting it to the wheel and a tensioner pulley to allow for suspension movement
For this reason, plus the need for inter-meshing spur gears in gearboxes, derailleurs are the lightest and most efficient geared drivetrains. Gearboxes may be more reliable, but they add too much weight, cost and drag to go mainstream.
Cedric Eveleigh wasn't satisfied with conventional derailleurs or gearboxes. Inspired by CeramicSpeed's Driven
drivetrain, he started brainstorming ideas to solve what he calls "the most glaring issue with mountain bikes" - derailleurs. On a ride in 2019, he thought of this concept and started building prototypes right away.
The basic idea is to separate the two functions of the derailleur (shifting the chain across the cassette and tensioning the chain). The lateral shifting mechanism with its guide pulley remains by the cassette but is tucked out the way. Meanwhile, the tensioner pulley, which normally hangs down amongst the rocks and roots, is moved to the bottom bracket. This massively improves clearance and reduces the risk of ride-ending derailleur impacts.
It also moves some weight from the rear wheel, where it harms suspension performance, to the mainframe, where it doesn't. Plus, because the two pulleys are larger than a conventional derailleur, and because there's no need for an additional guide pulley behind the chainring, Cedric claims drag is reduced compared to a conventional idler bike with a derailleur. As if that weren't enough, the tensioner is said to provide more consistent chain tension and better damping than conventional clutch derailleurs, reducing chain slap and noise.
Because of the position of the tensioner, the design only works with idler pulley bikes, and only ones with the idler positioned forwards out of the way. Perhaps this explains why nobody has thought of it until now; only in the last couple of years have idler bikes become more mainstream. The plan is for Lal Bikes to build the drivetrain components, and license the system to bike brands to design their bikes around it.
It won't be available until 2023, but we've ridden a prototype around the car park and the shifting worked flawlessly. Apparently, several bike brands have already shown keen interest in the idea, and given the original article
already has almost 200,000 page views, it seems the concept is interesting to many of you as well.
Whether the Supre Drive is viable as a production product remains to be seen, and we're not suggesting it's going to take over from conventional derailleurs. But this is the first radically new drivetrain concept we've seen in a long time that doesn't have readily apparent weight, efficiency, or shifting drawbacks.
That being said this is a cool take on the derailleur from an academic standpoint
But are they really? They aren’t really expensive, they are simple to set up, and while they won’t take too many direct hits off rocks, I wouldn’t consider them ‘fragile’.
I’m all for improvement and this invention looks pretty cool. But I think people tend to over exaggerate the negatives when it comes to derailleurs.
I’ve broken a half dozen darrailleurs in 15 years and bent more hangers than I can count on fingers and toes. There’s nothing worse than jumping back on your bike after a little get-off, then ghost shifting the first time you apply heavy torque. It’s especially irritating on modern 12-speeds with their tight tolerances. Good luck fixing hanger misalignment trail side.
With the rising popularity of electric shifting, the price of a replacement derailleur seems to start at €300 and go above €500 depending on model. That's expensive enough that I consider every invention that puts that €130-€500 derailleur more out of harms way as valuable.
Yeah, honestly, I've been alive for 40 years and I've never had a heart attack. The drama about them is overblown.
Anecdotes are not data.
However, I haven't broke a derailleur since the early 90's and I don't like that this seems to put a lot of limitation on suspension design...?
I can only get my hands on so much vitamin E baby! I won't have any time left to ride...
- It could potentially save you from having to replace a broken derailleur every once in a blue moon
- Proprietary system
- Less refined than competing products
- Requires proprietary frame design
- Adds complexity
- Greatly limits rear suspension design
- Not fully enclosed (susceptible to dirt and debris)
- Not entirely safe from sticks or rocks getting flung into the drivetrain
- Not entirely safe in the event of a crash
Compared to a gearbox and a classic derrailleur, this seems like a "worst of both worlds"-type of deal.
how's it gonna work on a HT or a non HP frame?
Have you tried just buying a derailleur lately? Getting parts from a small, agile company that manufactures onshore*, will most likely be quicker than waiting for Sramano parts. And of course, if the design pans out, less likely to break in the first place.
*It's going to be on my continent so that works in my favour, maybe not yours.
Some did agree with Maes but this will be terrain dependent: high pivots are getting pretty common where I live. Further, it's likely Cedric, working with established companies, will find a way to make the design work with low pivots
This one can have any practical meaning only when applied to normal bikes. The only way to do this is to place the tensioner lower (like a tensioner for some gearbox bikes), but then you would have to magically route the chain though the chainstays or ... make the derailleur hang ... So untill anyone proves it can be done for non-hp bike I refuse to accept this as a viable solution. You can believe in whatever you want, even in miracles, fairies, gods, lizard people, but this belief will not make them real.
I would like to own a hp bike but they will never get mainstream enough to validate a new derailleur system. Hp is basically a thing in DH an enduro (assuming you do not agree with Maes)and that's it.
That said, this is more like "Proof of Concept" of the year. When (if??) this design is refined and commercially available at a reasonable (for bike gear) price point, I'm all in. For now, it's just a working prototype mule.
Precision comes from making mistakes, learning from those mistakes and applying those lessons. If doesn’t mean you have to be striving to be a trials ace (I’m not!!!!) but it does mean you’re intellectually curious enough to strive to improve as a rider.
Be safe be well,
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