My Sirrus has 48-38-28 in the front, and 11-32 8 speed in the back. I usually ride at around 17-18 mph in the 38 ring. If I go faster than that, I usually shift the front to 48. What I am trying to say is - I rarely use the 11 teeth cog - only when I'm going downhill, i.e., 48-11/12 - and this is very rare. I prefer to coast downhill I'd like to reduce the gaps in the cassette - is there a cassette that has 32 as the biggest cog, but a much tighter range - say 13-32? I have only seen Sunrace 13-32 freewheels, not cassettes. I would prefer to stick to 8 speed so I don't have to change the drivetrain. Will I need to replace the chain as well? I don't have too many miles on the bike - just 1200.