7 speed cassette and 8 speed derailleur

[simcfarlane]

I'm sure this has been asked loads of times... but I can't find a definitive answer.

I've got an STX-RC RD-MC38 8 speed derailleur.

Can I run it with 7 speed cassette and some 7 speed Sachs Wavy shifters?

 

[Markybeau]

The derailleur and cassette shouldn't really matter, but the shifter might. I run 9's with 8's, and 8's with 7's with no issues. Indexing of the shifter and the gap between the cogs, on the other hand, needs to be compatible for an accurate shift. You haven't said what make of cassette you're using.

 

[simcfarlane]

A Shimano HG41 11-28 cassette.

 

[RetroDavy]

This suggests it should be ok
"Sachs Wavy Shifters | Retrobike" https://www.retrobike.co.uk/threads/sachs-wavy-shifters.67882/