Originally Posted by
xenologer
My old manager had the strategy:
just use 10spd chains on all his bikes.
they fit just fine on 6-7-8-9spd sprockets, since the narrowing of the higher speed drives is in chain plates and rivets, not the width of the rollers themselves.
It's not the space between the chain's plates that's the potential problem; it's the space between cogs and chainrings. A KMC Z33 6-speed chain is 7.8 mm wide. A 10-speed chain can be as narrow as 5.88 mm. With a chain that's 2 mm narrower, I've got a feeling I could end up getting the chain jammed between rings on some of my older bikes.