I've had 16t (stock), then 18t, now 17t - and liked all three a lot. You get used to what you have and adjust. I never disliked the 16t, even after a lot of 300-400 mile days, but the 18t just made more since. When it was time to replace the chain, I put on the Triumph America Chain and Sprocket set (17t), and debated a lot about it, but I have no complaints with it, either.
I will never go back to the 18t, and certainly never a 19t.
With my 17t now, I'm still running only about 4800 rpm at 80 mph, and have to be doing over 90 mph to be over 5k rpm....and I want so bad to stretch it out because she runs so good and smooth, at the higher rpms.
If I had the 16t back on now, with the pipes and jets, etc., I might be able to see what she feels like over 6000 rpm without risking jail time to do it.
I'll most likely just stick with the 17t I have now though. My old stock 16t only had about 10k on it I think when I went to the 18t, so I may just try it on again before the next chain swap is due.
There isn't another fast cruiser out there that can curl your toes like these can.
