Horrendous noises when pedalling

[nimrodstu]

I have just started hearing horrendous noises when pedalling my 7 week old Trek Powerfly 4 ebike. The sound is worse than clicking and clunking and I can’t tell exactly where it is coming from. So have uploaded a video here: https://youtu.be/G3X2tLHk4Bk. Has anyone had similar or know what if could be? I’ve not heard these types of noises before.

[Nicholas]

(04-10-2021, 03:14 AM)nimrodstu Wrote:  I have just started hearing horrendous noises when pedalling my 7 week old Trek Powerfly 4 ebike. The sound is worse than clicking and clunking and I can’t tell exactly where it is coming from. So have uploaded a video here: https://youtu.be/G3X2tLHk4Bk. Has anyone had similar or know what if could be? I’ve not heard these types of noises before.

Hello @nimrodstu !
We got a few replies from our community members via a post on Facebook.

• John: "At 7 weeks old from new, it is likely that the rear mech will need the cable tension adjusting, (even if the gear cables a pre-stretched which I doubt very much nowadays) even a couple of mm stretch over that period of time will prevent the gears indexing correctly, with the drive train not correctly meshing with the cogs on the rear cassette... On the vast majority of rear derailleurs, there is a tension screw that the gear cable passes through, as you are "pedalling" the bike by hand, unscrew the tension screw one click at a time until the noise stops (I'd estimate for a brand new bike it may take up to one complete turn, as the cable will stretch the maximum amount during the first couple of weeks of being ridden). NB: Do not fully unscrew this tension screw as it can be a bit awkward to refit, if it is virtually all the way out you will need to reposition the gear cable, to shorten it after winding the tension screw all the way, before backing it out one complete turn, then adjust as above. Once you have stopped this noise from being heard, index through every gear (up and down again) to ensure that they can all be selected and mesh correctly, without any noise...it may take a couple of attempts to get it right, making "one click" at a time adjustments."
• Paul: "On my Cannondale Trail neo 3. After two weeks and 66 miles had similar noises when pedalling. I discovered the 3 x T40 screws holding the motor in place had worked loose. Bought the t40 tool and torque wrench and fixed it."
• Michael: "Sounds like it wants to switch gears. Might only need to have derailleur adjusted.??????? Just a guess."
• Scot: "Michael, that was my guess too. Derailleur cable adjustment."
  

[nimrodstu]

Thanks all, turns out cassette lockring was loose, tightened that up and noise gone.