2021 Roam E+ - help with chain drop issue

[conix67]

Hi All,

Glad to find this forum. I'm a proud owner of 2021 Roam E+ GTS. I plan to share my experiences with the bike on various trips I made /w various assistance level in the future. However, I need some help first. My bike likes to drop the chain! This is a terrible issue to have while riding and can become dangerous.

My bike is currently with the dealer who said it's an issue that can be fixed with adjustments, and I was there today to pick it up after the service has been completed. However, the issue was still there (rode around empty parking lot next to it with speed bumps) so I was forced to leave the bike with the dealer and left. I'm not confident if they know the exact cause.

It usually happens on a flat ground hitting a bump or going over a speed bump and appears to happen at high gears only. I've ridden in trails with bigger bumps without this problem but I believe the gear was usually at lower settings like 7 or below. The bike is less than 2 weeks old, so there's no wear or tear to affect its performance, at least not yet.

I will wait until tomorrow to see what the dealer comes up with but in the meantime, I'd like to hear from anyone with similar experience, or potential solution. Other than this problem, I've been very happy with the bike overall.

 

[TheEqualiser]

I'm not really an MTB guy but it sounds to me like your bike would benefit from having a clutch on the rear derailleur which I assume the stock one doesn't have. I thought that clutch derailleurs were really only to compensate for the huge differences between the smallest cog and chain wheel and the largest cog and chainwheel which should not be an issue on your bike but a clutch should certainly limit chain drop. Then again maybe you just have too many links in your chain or your derailleur tension is too low.

 

[conix67]

I'm not really an MTB guy but it sounds to me like your bike would benefit from having a clutch on the rear derailleur which I assume the stock one doesn't have. I thought that clutch derailleurs were really only to compensate for the huge differences between the smallest cog and chain wheel and the largest cog and chainwheel which should not be an issue on your bike but a clutch should certainly limit chain drop. Then again maybe you just have too many links in your chain or your derailleur tension is too low.

Correct, mine does not have the clutch. Too many links possible, I did not count but everything is stock so I assumed they put the correct one for this design. Is there a way to adjust the derailleur tension?
If the chain length is reduced by removing few links, what would be the downside? I think reducing the length of chain will definitely help.

 

[TheEqualiser]

Too many links would be unlikely if the chain is original. The downside to removing any could be that your chain would be too tight to run properly or even shift to the lower gears (larger rear cogs). Have a look at this video

and Google "B screw adjust rear derailleur" in relation to tensioning the derailleur.

 

[conix67]

I'll probably get my bike back tomorrow and look at this first..