Chain catching on derailleur

[Dfects]

Hiya

I just purchased a GT outpost 2nd hand as a cheap replacement. I've given it a quick degrease and relube, but I've noticed something odd with the rear derailleur, the chain seems to be catching it! Pretty sure this isn't normal...

Only seems to happen on the smaller 2 cogs:

Sorry for the crappy photo.

Any ideas what might be wrong? wrong chain? gear shifts seem nice and smooth after a little adjustment.

 

[Gerry Attrick]

Chain is too long more than like. Put the gears in the biggest rear sprocket and the biggest front sprocket and the rear derailleur jockey wheels should be vertical.

 

[Gerry Attrick]

Useful article on determining correct chain length here.

 

[I am Spartacus]

Chain is too long more than like. Put the gears in the biggest rear sprocket and the biggest front sprocket and the rear derailleur jockey wheels should be vertical.

If you mean biggest by largest gearing.

To clarify
check jockey wheel vertical alignment
smallest rear sprocket/largest cr combination

(as per Shimano tech doc)

 

[Gerry Attrick]

If you mean biggest by largest gearing.

To clarify
check jockey wheel vertical alignment
smallest rear sprocket/largest cr combination

(as per Shimano tech doc)

Thanks for correction. Fingers type faster than brain can work!

 

[I am Spartacus]

No worries... still scratching me head on my own issue....

 

[Dfects]

Fantastic! Thanks for all the info!

I've just gone out and dropped a link, much happier now with no catching and good changing.

I did this before seeing the link on checking chain length, so i'll give that a check before my next ride!

Does breaking the chain cause any weaknesses? Worth replacing?

Thanks again for the help.