Originally Posted by jeff williams
Are chairings speed AND chain specific? I've some that fit the spider but are from a 5 speed train ( thought it was a 6 ) What speed does the narrow chain come into use- 6?
There are some track chainrings and cogs that require using a 1/8" width chain. But rings and cogs for multi-speed stuff require a 3/32" width chain.
Technically, there is a slight difference in cog and chainring thickness going from 5 to 6 to 7 to 8 to 9 speed, but the difference is very small. The main difference is in the thickness of the spacers between cogs, and in the offset of the teeth on the inner chainrings. In other words, you can use the chainring from the 5-speed bike with 5, 6, 7, 8, or 9 speeds in the rear. The chain you use should match the spacing of the rear cogs.
normal - 5, 6
narrow - 5, 6, Ultra6*, 7, 8
ultranarrow - 9
You can use either a "normal" or narrow chain for both 5 and 6 speed standard spacing. My first 6-speed bike came with a "normal" chain but it ran a little noisy in certain combos so when it came time, I replaced it with a narrow.
*The Ultra6 was a 6-speed freewheel fit in the space of 5 and used approx. the same width spacers as 7 and 8 speed stuff.