Chain & chain ring quality

Electrically assisted bikes, trikes, etc.
Posts: 1
Joined: 10 Jun 2020, 5:18pm

Chain & chain ring quality

Postby Rasher » 11 Jun 2020, 11:45am

I have a 2019 Trek Powerfly Sport. Despite mostly riding & pulling away in ECO my chain and chain ring don't last very long. The chain ring on the right in the photo is made by FSA & was supplied with the bike (which had to be changed with the chain & cassette at 1300 miles) and the one on the left (from Trek) is the one I have just had to replace (and the chain) some 800 miles later. Can anyone recommend parts that will last longer?

Bonzo Banana
Posts: 104
Joined: 5 Feb 2017, 11:58am

Re: Chain & chain ring quality

Postby Bonzo Banana » 11 Jun 2020, 5:42pm

I think this is normal for mid-drive motors especially this Bosch model, they have the reputation for chewing through chains and the small chainring will wear out very quickly. Just hope your issues remain outside the motor, when the motor starts failing the bills can be astronomical. You are putting all your own power and the power of the motor through the same drivetrain. If you are a heavy rider or have many local hills or both the wear rate will be excessive but even in ideal conditions they will still not last a long time. It's a bit like German cars, performance is good but reliability and maintenance costs can be expensive. Mid drive motors are really the performance end of the ebike market. They are not the value end. If you are going to try to find more longer lasting components you may want to do all 3 together, chainring, cassette and chain rather than strengthen one component on its own like the chainring.

Posts: 15
Joined: 16 Sep 2019, 6:39pm

Re: Chain & chain ring quality

Postby Xbigman » 16 Jun 2020, 3:11am

I don't know what the specific issue is with your bike but I can tell you this is not typical for Bosch drives. The chain should do between 1500 and 2000 miles dependent on the combined rider/bike weight. The chainring and cassette should last through multiple chains. I'm talking standard chains not the expensive ebike chains.

Pulling away in eco mode makes very little difference. Its the weight that counts. Me plus my bike weigh 143kg and at 3000 miles I'm about to change the chain and still have the original cassette. The Chainring I switched out for a smaller one at 1500 miles but that is showing almost no wear.

I can only suggest you check the chainring is not rubbing and keep your gears indexed properly. Clean and Lubricate the the chain regularly. Even if you are heavy and hard on the gears you should be getting better mileage than this.