Merida e400 four derailleur slipping, 550 km.

[Jayshot]

Hi everyone, I own a merida e400 four, Just recently the lowest gear 12 i believe is slipping and clunking, I have tried to sort out myself and had a twiddle with the derailleur screws but seems to be getting worse, Any help would be nice, Farnham.

 

[Anton]

You will need to learn how to adjust a rear derailleur, there are some videos on: Youtube:

If you simply play with the limit screws it will most likely get worse rather than better. There is a process to adjusting a rear derailleur and it takes a lot of patience to learn how to do it right.