I beat the shit out of this bike a couple weeks ago and am only just now getting time to fix it. I'm sure the derailleur got banged around so I'm wondering if some part of it is bent or broken? I have no idea what I'm doing or what to even google to get answers so I'm hoping y'all could at least help tell me what I'm looking at?
Was pedaling backwards for the video to make the derailleur movement more obvious but it behaves the same going forwards, minus the chain dropping (and the chain pops back into place when you pedal forwards)
There is some wiggling/movement in all the gears but that scraping noise and the chain dropping only happens on the highest one
Sorry for all the helpful info I'm probably missing. What I wrote is pretty much the extent of my bike knowledge but I'm trying to change that 🙂
EDIT: Seems like the consensus is the B screw needs to be adjusted but it also seems like the B screw on this particular derailleur (Shimano tourney) does absolutely nothing so we're at an impasse. Will talk to local shop about options. Thanks y'all!
Wiggling/"scraping" noise from rear derailleur when in the highest gear
byu/NeonHorse47 inbikewrench
by NeonHorse47
6 Comments
Pedal forward and see if the noise disappears
I don’t know why this is so common here, but start with working on it right side up – it’s not designed to work perfectly upside down. Not saying something isn’t right, but at least work on it in the right setting.
The pulley hits the cog; adjust the B screw (the one at the back) by turning it clockwise
[https://www.youtube.com/watch?v=y3x13dD0UiQ](https://www.youtube.com/watch?v=y3x13dD0UiQ)
I’d recommend you re-adjust your rear derailleur. Park Took has a good guide and has a great video describing the process. As mentioned earlier it looks like a B screw issue but you’ll want to check everything.
https://www.parktool.com/en-us/blog/repair-help/rear-derailleur-adjustment
And maybe time to change the shifter cable too!
Good luck!
B tension is the problem. But they don’t really have adjustment for that on those derailleurs. So I would definitely replace it if it’s a problem. Or otherwise flip the bike over and ride it.
First remove dork disk.