I've been pondering my options to give my old evo longer legs, changing pulleys, six speed box....all that.

Came across this site - Big Boyz Cycles. I can't actually verify it's accuracy, but it looks about right to me...and it's very handy for working out speed vs RPM and so on....

Check it here  http://www.bigboyzcycles.com/Gearratio.htm

hi colstah , most softail evos are doing 2500 rpm at 100 ks with standard setting, which is normal for most 5 speed bikes , some fxr and dyna slightly lower , around 27-2800 rpm at 100 ks ,

Yeah Dynoharley, I don't have a tacho on the bike, but I'd think that's right.

The 'problem' I have is that the pack sometimes tends to run at 120-140 on the open road and my evo feels like it starts to work a bit too hard for my liking, after 120. So with the six speed (with an overdrive of 0.86) I should be able to do 140 at about 2900 rpm, by that calculator, rather than about 3400 on the five speed (all with stock pulleys), as it is now. And I have to say that to me, it feels like it's working harder than the theoretical 3400 rpm should be doing.

I could change the transmission and rear wheel pulleys to 34/61 respectively to get about the same effect, but I'd lose pulling power in the lower gears, they'd all be effectively taller. And anyway, once you talk about changing pulleys and possibly a belt, that's getting close to the cost of a cheaper six speed box.

If anyone can punch holes in the logic/theory, please do so....

http://www.gearingcommander.com

This is the site I use all the time....