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Ceramicspeed Driven update

Ceramicspeed Driven update

Ceramicspeed Driven update

(OP)
Ceramicspeed has continued development of their Driven drive system for bicycle propulsion. Original thread: https://www.eng-tips.com/viewthread.cfm?qid=443622

Update links:
https://youtu.be/DsUt87NB0Ck
https://www.ceramicspeed.com/en/cycling/d3/driven-...

Their engineering team has been very creative and busy developing amazing technology to address the issue of making the Driven system shift: 'step and follow' drive pinions with a torque-decouple bearing synchronizer. Though they show a shifting demonstrator model and CAD animations, I don't think a shifting system has actually been ridden and shifted by a world-class racer to show it can deliver power reliably and efficiently at high input levels.

Their demonstrator still appears to be an interesting concept that promises a lot but still requires a lot of work:
1. The rear cog set has cogs inward to the hub OD but the driving pinions cannot reach those cogs due to the geometry requirements of the step and follow driveshaft, and the material required to make the frame dropouts to attach the wheel axle. So the extreme range of ratios shown does not represent the true working range.
2. The inherent side force created by the driving bearing in the driven cog will try to deflect the drive cog cluster and driver cog apart. The stiffness of the drive to maintain engagement will be challenging, especially at the outer/lower ratios.

The demonstrations appear to be orchestrated to some level. Ceramicspeed does not show the system in use at the smallest radii. They stay within what appears to be a known good range. The track test never zooms in in on the setup used by the rider. I think he is riding a fixed ratio setup - track riders do not shift gears. I don't think they have allowed independent testing to confirm their claims for mechanical efficiency - but that is not uncommon for many products in development. I get it - to keep the R&D dollars flowing you have to emphasize the successes and soft-shoe the remaining technical challenges.

It will be interesting to see if this is a viable tech or a 'better mousetrap' that is different but not really better. A chain and two sprocket set are rugged, efficient, low-cost, and reliable.

RE: Ceramicspeed Driven update

(OP)
The technology being developed at New Labs purports to increase mechanical efficiency and it does not add complexity.

https://www.newmotionlabs.com/new-motion-labs-rein...

The redesign of the sprocket seems to be quite an elegant improvement: a subtle change of geometry addresses the sliding motion intrinsic to a traditional roller chain drive, adding more links per length of chain allows for better mechanical wrap of the chain over the sprockets.

This looks like a more commercially viable product than the Ceramicspeed Driven system. Only time will tell if either are adopted by industry. Without buy in by the majors of the industry the technology will die on the vine.

Edit
The New Motion system may have its own Achilles heel: it does not appear to support shifting. No examples of a multisprocket cluster are shown, nor a derailleur, etc.

RE: Ceramicspeed Driven update

People are claiming much better longevity increase using and maintaining a dry wax lube on the chain. I've started using a hot wax lube and it holds on to almost no grit or dirt, even after a race with a few sand traps on the course.
https://zerofrictioncycling.com.au/ , or for that matter, just keeping things clean will prolong the life.

Gates belt drives (and an internally geared hub) are what people seem to be using for winter commuting which eats up chain drivetrains. Guy I talked with claimed 10 or 15,000 miles on his, I forget.

RE: Ceramicspeed Driven update

(OP)
Yes, the dry wax treatments using a heated wax dip seem to be getting very positive reviews and results.

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