Schaltrollen

Probably, yes. Have a close look at your current jockey wheels, if they are worn and if shifting can be vague, even with new cassette, chain and cables - then replacement jockey wheels could well be the answer. Jockey wheels spin at around 400 rpm for all the hours you spend riding, they also get taken for granted and largely forgotten about. Whilst checking jockey wheels, if your bike's rear derailleur is also well used, and not as tight as it once was, it could be more cost effective to replace the rear derailleur.

We always recommend following manufacturers instructions for fitting any component. The Youtube channels of Park Tools and GCN Tech have very indepth and comprehensive advice for completing all sorts of jobs on bikes, these are also worth watching particularly if you are inexperienced or unsure.