Posted by Dan Radford on 23rd Jan 2020

​Gates carbon belt drive or chain?

In the last few years we have seen belt drives becoming more popular on premium electric bike brands like Riese & Muller. But what are the benefits and are there any downsides to this new technology?

Riese and Muller electric bikes come with a large range of options on all their bikes and can be built to order from the factory within 3-4 weeks. One area of most interest to our customers is the option of a belt drive compared to a chain drive. I have tried to highlight the main differences to help you whan making your decision which route to go.

Let's start by considering the faithful chain drive.

Traditionally bikes have been fitted with a chain to transfer the power you create from pressing on the pedals through some form of gearing system into the rear wheel to create forward drive.

Having been brought up riding bikes fitted with chains I can vividly remember the sticky oily mess on my hands after putting a chain back on the front chain ring. And I’m sure my mum can probably remember the clothes I ruined by wiping my hands on them! Whilst chains still bounce off, mainly when riding off-road, I have now realised it’s better to wipe my hands on the grass, not my t-shirt.

Before becoming a qualified bike mechanic and as occasional cyclist prior to discovering electric bikes, I had wrongly assumed chains were pretty robust and needed little or no maintenance, other than a squirt of any old oil I could find in the shed when it was rusted!

A chain wears and and requires preventative maintenance and regular replacement.

The reality is a chain wears and stretches over time and if not replaced regularly, can cause excessive damage to the front sprocket and rear cassette. A well-lubricated chain (using bike oil) will mean a chain runs smoothly, and quietly, changes gear well and will wear other components slower. It will still stretch, but you can check this using a chain checker tool and it is recommended you replace your chain when it is maximum 75% worn. By doing this you should get three chains for every one rear cassette you replace.

Trying to work out when to replace a chain based on mileage isn't really an option as chains will wear at different speeds on different bikes. And electric bikes are likely to wear chains faster due to the additional power delivered by the motor. 

As an example, I checked the chain on my 2019 Riese and Muller Homage GT touring running a Bosch performance CX motor, with a Parktool CC-2 Chain Checker. The chain is approximately 25% worn and the bike has covered 331 miles. So I would be expecting to replace this chain at around 1,000 miles. It has an 11-speed cassette so I would expect to pay in the region of £55 plus fitting for an e-bike specific replacement. If I were to leave the chain to wear completely, it will begin to hook the teeth on the sprocket and rear cassette. It this point, replacing the chain only will mean it is difficult to change gear and there may be some jumping. The cost of a new cassette on this bike will be approximately £80 plus fitting. So it is worth staying on top the maintenance to save a few £'s. All these jobs are completely possible for the home mechanic with the addition of some of the basic workshop tools.

Maintenance on a belt drive is significantly reduced as it does not require oiling.

Probably the biggest benefit of belt drive is the lack of need for maintenance, specifically oiling. If you are anything like me, you will go for a big ride at the weekend exploring new trails whilst getting generally covered in mud. It’s hours of fun and really reminds you of how it felt to be young and care-free. Then, when you get home, you place your bike in the garage whilst you go inside to warm up for five minutes. The next time you see the bike is when the sun comes out and you want to ride it to work but the chain, caked in mud, has dried out and is maybe not in perfect condition….with a belt drive you don’t have this problem. Whilst I don’t advocate leaving your bike for a week before you clean it, the reality is you will do far less damage if you are running a belt.

But a belt will still stretch. Depending on the system you have this can be either irrelevant or a really cool thing to impress your mates with. Riese & Muller use Gates Carbon Belt drives on their bikes, and not only do they look really cool, and the way you check tension is even cooler.

If you can tune a guitar you can correctly tension a belt.

If you have a bike like the Riese & Muller Multicharger GT Rohloff, then do this. Gates have an app that you can download to your smartphone for free which is essentially like a guitar tuner. You hold it alongside your belt and give it a twang. The recommended frequency is 35-50Hz and there are two screws you would turn to push the wheel back and increase the tension if needed. More of a visual thing, so I will post a video to show you how to do this some time.

Alternatively, the bike may have a belt tensioning system built-in like on the Rese & Muller Superdelite GT Rohloff or Supercharger2 GT Rohloff. This system is designed to maintain the tension on the belt and having checked the belt on my Delite GT rohloff demonstrator it is tensioned to 50Hz.

And the final thing to consider when deciding belt or chain is going to be choosing which final drive or gear system you would like. If you you just love a rear derailleur and cassette then it has to be a chain. If you like the idea of an Enviolo or Rohloff hub, then they are going to come with a belt drive as standard in the Riese & Muller 2020 range.

Conclusion

When deciding if you should go chain or belt drive answer these three questions, after that it’s all pretty straight forward;

  • How important are bragging rights?
  • How good are you at remembering to maintain your bike?
  • What final drive system do you want?

Give us a call

If you think you know which option you want to go for, then the next step is to try it out in a real-world situation. At edemo.bike, we have a large selection of Riese & Muller bikes available to try before you buy. 

Still undecided? Why not book a two hour guided on and off-road tour. You can try a couple of different bikes to see which you prefer. Call now on 01453 834300 to book.