How to choose between Belt Drives and Chain Drives

May 30, 2022

What Is the Most Common Drive System for Ebikes?

The most common drive system uses a chain to drive power to the wheels. This drive system has been in use for at least a century. Most bicycles, electric bikes, and motorcycles use chains, and it may be the only kind of drive system you have personally seen. However, other drive systems exist, and the belt drive is among the most well-known alternatives to the chain drive.

                                                 

What Other Drive Systems Exist for Ebikes?

Other drive systems include the belt drive, which uses a belt instead of a chain. The belt drive uses a belt made out of a single part instead of a chain, which is made up of many factors. The belt will have tiny grooves to fit into the two pulleys – one on the gearbox and one on the wheel.

                                                 

While belt drives are probably most common after chain drives, there are some other types of drive systems out there as well. These include shaft drive, string drive, treadle drive, and direct drive, though these are not common (except direct drive, used for unicycles).

 

Chain Drives

Pros :

  • They are cheaper: Chain drives are generally more affordable than less common belt drives.
  • They are familiar and easy to find: If you need to replace your chain, you can find a new chain bike chain online or at your local bike shop. Most bike shops sell chains, freewheels, cassettes, and chainrings. If your chain breaks or a cog wears out, you can easily find a replacement almost anywhere, even in remote parts of the world.  If you’re choosing a chain drive to make finding parts easier, 9, 10, 11, or 12-speed are your best bet. These are available everywhere.
  • Compatible with most bikes: Chains are compatible with most bikes, regardless of the kind of motor or frame they have. However, some ebike require a particular chain Belts.
  • You can take them apart: Since chains are made up of many parts, it is easy to take them apart. On the other hand, it is impossible to take a belt drive apart, so you will have to take apart the frame instead of removing it or replacing it.
  • You can fix a broken chain: You can always fix it if a chain snaps. A belt drive comes in one piece, so it is damaged for good if the belt snaps.
  • Chains are more efficient at low power inputs: For casual cycling, you’ll burn slightly less energy using a chain drive.

 Cons :

  • They can rust: Belt drives don’t rust as chains do, making it more of an issue to ride your bike in the rain or park it outside.
  • They wear out quicker: Chains are not as durable as belts.
  • They can be loud: Chains make more noise than belts due to the chains’ material and the many parts involved. They can squeak and make other annoying noises.
  • They require more maintenance: Chains require a lot more maintenance. You have to clean them often and apply wet or dry lube to ensure they keep running smoothly. You also have to check for rust and ensure the chain isn’t worn out.
  • Chains loose efficiency over time: As chains wear, they tend to ‘stretch.’ This is the loss of material from the chain from wear. As chains wear out, they become loose. This reduces tension and can lead to slippage. Cogs can also wear down to a point where the chain doesn’t fit quite right. This can create additional friction, which causes inefficiency. Not cleaning and lubing the chain often also enough reduces efficiency. This costs you energy. Belts maintain their shape and wear much more slowly. They also wear at the same rate as the cogs. This means they keep their efficiency longer.
  • Dirtier: Chains require frequent cleaning and greasing. It’s a messy job. While dealing with your chain, you’ll eventually get grease on your hands and gear.
  • Heavier: A chain weighs over three times as much as a belt. For example, an average 9-speed bike chain weighs around 450 grams. A Gates Carbon Drive belt weighs about 250 grams. You’ll also need to carry a chain tool, lube, spare links, and something to clean when you’re touring. Maybe even an entire extra chain. This adds a significant amount of weight. With a belt-drive, all you’ll need is a spare belt.
  • Chains are more mechanically complex: Chains have a lot of moving parts. Each link has pins, outer plates, inner plates, and rollers. If a part gets bent or gummed up, it can prevent your chain from working properly. Belts are simply one continuous piece of material. If you’re using derailleurs, your drive system is less complex than if you use an internal gear hub.

                                                 

  • Chain drives don’t last as long: An average bike chain lasts around 3,000-5,000 miles if adequately cared for. Every time you change your chain, you’ll probably have to replace your cassette. Belt drives can last 10,000-20,000 miles before they need to be replaced.

 

Belt Drives

Pros :

  • Less maintenance is required: Belt drives require less maintenance. You don’t have to oil and lube the belt like you have to with a chain. For the most part, you can leave the belt as it is, and it will continue to work great.
  • They last longer: Belts wear out much slower than chains. - An adequately maintained belt drive can last 3-5 times as long as a chain drive. Some riders have gotten 20,000 miles (around 30,000 km) out of a single belt. Most chains only last 3000-5000 miles. This means that although belts are more expensive initially, you may spend less in the long run due to not having to replace them as often (and not having to buy lube).
                                                 
  • They are quiet: Since belts are made of rubber instead of metal, they don’t make as much noise. If you enjoy peaceful, quiet rides in the morning while enjoying nature and the birds singing, you may want to opt for a belt drive.
  • They stay on the bike: You may have experienced a chain falling off the bike if you’ve biked a lot. This won’t happen with a belt; you won’t have to stop on the side of the road to put your chain back on.
  • They are lighter: Chains are heavier than belts. Belts weigh down your electric bike a lot less than chains. Also, you won’t have to carry around lube on long trips just in case your chain needs lubing.
                                                 
  • The driveline is always straight: The most efficient driveline is a straight line between your front chainring and rear cog. The driveline is always straight with a belt drive because the belt never moves between cogs. The shifting all happens in a hub or gearbox. A chain often runs at an angle. This happens when you’re running toward your gear range’s high or low extremes with a derailleur setup. This is inefficient and wastes energy. Of course, if you’re running an internal gear hub or Pinion inner hubs with a chain, the driveline is also straight.
  • No corrosion: Belts are made of modern synthetic materials, including nylon and carbon fiber. These materials don’t rust. This property makes belt drives an excellent choice for areas where corrosion is expected, like near the ocean.

Cons :

  • They are more expensive: Belt drives are more expensive than chain drives. This is because the actual endeavor is more costly to produce and because they require specific inner hubs like Rohloff(Bikonit-MD1000, Bakcou-Storm Jäger,Rambo-Venom. If your belt does snap or get worn out, it will be more expensive to replace it.
  • They are harder to replace: It will be harder to find a replacement for your belt, especially if you are on the road and go to the nearest store. It is also harder to replace a belt because, as mentioned, you can not simply take it apart. You will have to take apart the frame instead. If you are in a more rural area, finding a replacement maybe even more complex.
  • They can be less efficient: This varies. Belt drives are more efficient than chain drives at high power outputs and when going up inclines. However, belt drives are less efficient than chain drives at standard or low power outputs, which is most likely what you will be using if you are doing city riding.
  • Belts are less efficient at low power inputs: If you’re cycling casually, you’ll burn more energy while riding a belt-drive bike vs. a chain drive.
  • Belt drives cost more than chain drives: A new belt will cost you $80-$100. A new front and rear sprocket will cost around $60-$80 each.
  • Spare parts are harder to find: If you’re riding in the developing world or somewhere remote, finding a replacement belt or sprocket will be difficult or impossible. Many small bike shops and department stores don’t stock parts for belt-driven bikes.
          You can learn more about the belt drive from this video:

 

So, Which Is Better for You?

There is no absolute answer to this as it depends on your own requirements. If you are on a budget or for mountain downhill, consider the standard chain drives. You may have to replace them more often, and you may have to spend more on maintenance, but the cost of maintaining and replacing chains is not very high. At this situation,chain drive is the best choice.

On the other hand, if it is a daily urban commute, you can choose a single belt drive, or if you are a high-power user, such as hunting and other activities, you can consider going for a belt drive. Or you want to try something new, have a larger budget, and are tired of constantly cleaning your dirty, grimy chain and getting lube all over yourself and your garage floor. This also applies if you are tired of always putting your chain back on when it falls off or replacing it when it wears out or snaps. At this situation,belt drive is the best choice.