Originally Posted by
joesch
I know that crank rings have gone from 3x and 2x to 1x (one by) and larger teeth counts like higher 50s to now higher 20s but are there different teeth widths than 1/8 and 3/32 like chains?
Curious since some rings are now termed 11 and 12 speed so was not sure if the widths have decreased from 3/32?
This question is based on SRAM NX crankset where each tooth's thickness is CNC machined to work seamlessly with the chain's inner and outer links making it a better 11/12 spd crank. This CNC machining must change the 3/32 width? Also these rings are only offered in 28T, 30T, 32T, 36T sizes.
7 speed HG cassette sprockets are 1.85 mm wide, Shimano 10 speed sprockets are 1.6 mm wide, and the chain inner width has become slightly narrower to suit this, from 2.38 to 2.18 mm. The machining to suit inner and outer links is known as narrow-wide, the shoulder of each outer-link tooth is wider to better align the following inner link. Generic narrow-wide chainrings are readily available, I've used them on 1x7 and 1x10 bikes and they run smoothly. Obviously they only work in 1x systems with even-number chainring tooth counts.