When we look for drivetrain options on a bike, we instinctively think of the chain. There's nothing strange about that, as it's a system that has been in use globally since the end of the 19th century. But there is a company, founded over 100 years ago, that is on the right track to change this trend.
Chain or belt drive?
Gates Carbon Drive is a bicycle-specific product of Gates, a company that has been making belt drives for industrial, automotive and replacement applications since 1911. Over the last 15 years, the aforementioned bicycle system has evolved so much that we can distinguish 4 different component sets optimized for specific applications; CDX, CDC, CDN, ST:
- CDX: High performance commuter, trekking, mountain and cargo bikes, eBikes and bikes for extreme conditions.
- CDC: Urban commuting, mid-range eBikes
- CDN: Hub-drive eBikes
- ST: Leisure bikes (3 speeds or less)
These are not just belts, but complete systems, including front-rear chainrings or even cranksets. You can be sure of compatibility with the gearbox, as it was developed in collaboration with Shimano, Rohloff, Pinion, and the same applies for the drive units; Bosch, Shimano STEPS', Brose, Yamaha, Bafang, pretty much all the big names can be used with the system.
The belt itself is very strong.
It takes its name from the carbon fiber tensile cords in one of its layers, covered by a layer of ribbed back on the top and HTD tooth polyurethane on the bottom. The latter has a design called "centertrack", through which the chainring guides the belt evenly.
To ensure that the belt is sufficiently tight and remains so under load, a strong and rigid rear triangle is required. Without it, the frame can be so distorted when stepped on the pedal the belt could jump on the teeth. The ideal tension can be checked at home by using a mobile app.
The question may arise as to how efficiently this system can be used, given the resistance that rolling over a large surface (11mm wide) will create. Well, at a general low power output (below 212 watts) there is an efficiency deficit of 0.3-1% compared to the chain, while at resistance equalization (212 watts) this small difference is eliminated.
So a basic user will not feel any of this.
If you think about what makes urban mobility even easier, you can say that a quiet, cost and service-free drivetrain is definitely a huge step forward.
Pros:
- Easy maintenance: It does not require lubrication, so it does not collect dirt. An old toothbrush is all you need to clean it and quickly remove the mud/dirt stuck between the teeth. The amount of money you save is worth mentioning here.
- Light: The weather-resistant polyurethane shell has strong, non-stretch carbon fibre tensile cords. A lightweight and durable combination.
- Quiet: In addition to a significantly longer lifetime (3-4x more than chain), it is almost completely silent. There are no metal parts that could hit the chainstay nor cogs that would inevitably make noise.
Things to consider with this system::
- Compatible only with hub-geared bicycles. The belt does not have a lateral bend, so it cannot run up and down on the rear cog.
- The belt is a continuous, uninterrupted unit that frame designers must adapt to by designing an opening on the rear triangle. This makes the system interchangeable.
The advantages of the belt-drive system are clear. It's a great choice especially in urban environments, when you don't have the time or inclination to deal with maintenance, you just want to get on your bike and get to your destination quickly, quietly and efficiently. We at Gepida are excited to see what the future brings in this area.
Gepida offers City and Special models with belt drive.
The copyright of the original content and graphics generated and owned by Gates Corporation.
