Originally Posted by
Grand Bois
You just remove 1 cog and one spacer from a nine speed cassette. You'll need a nine speed shifter and a nine speed chain. Why not just buy a seven speed cassette with bigger cogs?
If I remember correctly it wasn't gearing but shifters that prompted the 8 of 9 on 7. 7 sp is still popular but shifters are hard to find. You can use the very popular and easy to find 9 sp brifters on a bike that was originally set up as a 7 sp without new rear hub or cassette hub body transplant.