Originally Posted by
icemilkcoffee
There is a strong chance that this will happen when you put a 10 speed chain on a 7 speed setup. And 'good index' will not help. It's not a matter of indexing- the chain just physically drops into the gap between the chainring.
10 sp chain on a 9 sp drivetrain seems fine though.
Yes, that's why I corrected the post you're quoting further in the thread:
"Agreed about 7-speed, my brain tends to think in 8/9/10 and I missed that one. I wouldn't try a 10 chain on a 7-speed."