Bicycles

Supre Drive system lifts mountain bike drivetrains out of harm's way

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The Supre Drive drivetrain can be incorporated into both full-suspension and hardtail mountain bikes
Lal Bikes
The swingarm frame helps to protect the derailleur
Lal Bikes
The chain-friction-reducing oversized pulleys on the derailleur (pictured) and tensioner are said to further boost the system's efficiency
Lal Bikes
Cedric Eveleigh with one of his test bikes – he hopes to have Supre Drive market-ready by 2023, and anticipates that it will ultimately be in the price range of conventional high-performance drivetrains
Lal Bikes
The Supre Drive drivetrain can be incorporated into both full-suspension and hardtail mountain bikes
Lal Bikes
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The rear derailleur is one of the most fragile components on a mountain bike, subject to getting bent or jammed up with trail debris. That's where the Supre Drive drivetrain comes in, as it moves the derailleur up and divides its functions between two locations.

The prototype system was invented by Canadian mechanical engineer Cedric Eveleigh, who is commercializing the technology via his Lal Bikes company. It addresses one of the key problems with existing derailleurs – the fact that they hang down close to the ground, supported only at the top.

In Supre Drive, the single-pulley derailleur body is mounted on a system-specific rear swingarm (it can also be used on hardtail bikes), where it sits to one side of the cassette – not beneath it. There, it performs its usual task of moving the chain back and forth between the sprockets. It's rigidly mounted at two points, however, plus it's protected against side impacts by the overlying swingarm assembly. This means the bike can be laid down on its drive side without any risk of bending the derailleur.

Of course, along with moving the chain sideways, conventional rear derailleurs also keep it tensioned. In the case of Supre Drive, that function is performed by a separate hydraulic-damped tensioner arm which pivots around the bottom bracket axis. This arrangement allows a consistent amount of tension to be applied throughout the gear range – with regular derailleurs, the tension increases as the gears get lower.

And as a side benefit, because the chain is held relatively high, there's reportedly no chance of it slapping against the ground when the rear suspension compresses during hard landings. When removing or reinstalling the rear wheel, the tensioner can be locked to provide the required chain slack.

Cedric Eveleigh with one of his test bikes – he hopes to have Supre Drive market-ready by 2023, and anticipates that it will ultimately be in the price range of conventional high-performance drivetrains
Lal Bikes

Weight-wise, the system is claimed to be 100 to 200 grams heavier than a regular Shimano XT drivetrain on a high-pivot mountain bike, although it actually has about 130 grams less unsprung weight – this is due to the fact that the derailleur is shorter, plus less of the chain is located near the cassette. The total length of chain required is about the same as that presently used on high-pivot bikes.

Importantly, Eveleigh adds that Supre Drive is much lighter than internal gearbox-based drivetrains, which are an existing alternative to conventional derailleurs. He claims that it also produces less drag as the rider is pedaling, making it more efficient at converting their muscle power into forward motion.

The chain-friction-reducing oversized pulleys on the derailleur (pictured) and tensioner are said to further boost the system's efficiency
Lal Bikes

The system is compatible with third-party hubs, bottom brackets, cranks, chains, shifters and cassettes, although it does obviously have to be built into the bike from the start – it can't be retrofitted onto existing bikes. To that end, Eveleigh plans on selling the components to bicycle manufacturers, which will in turn incorporate them into their bikes. He tells us that he's presently collaborating with one frame company, but is open to enquiries from others.

Supre Drive has already been built into two test bikes, one of which Cedric puts through its paces in the video below.

Source: Lal Bikes

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6 comments
Daveb
That is a bonafide super invention. Great luck to ya Lal Bikes!
David V
Nice concept. But that's a lot of moving parts just next to the ankle and lower leg.
Brian M
See the advantages, the only downside I can immediately see is that there are moving bits closer to the rider - never a good thing especially if the bike is used for other uses where the dress code is different!

Wonder if any thought given to the integration with electric drives, once you have ridden an electric assist mountain bike you wouldn't want to go back (ok personal choice !) and it makes it more useful for other task such as a commute to work.

PoconoPuppy
Looks awesome and a torched derailleur is one of the reasons i don't MTB. Also, this kind of setup is not typically for the casual commuter, but rather the serious MTB'r that regularly jumps off stumps and over rocks and through the woods where serious damage often occurs to the typical derailleur. I say nice work and cant wait to see it on the trials.
freddotu
it's rare that an innovation in cycling power trains appears and is a true innovation. I wish this young fellow the best in his future with this invention. I'm impressed with his design and hope to see it on the market.
SteveMc
Superb! Well done Cedric :)