Gearing Calculator
 

My co-worker is changing the gearing on his bike soon and he showed me this website. Now I'm sure its not an exact science like it looks like, but I'm sure this would be helpful to all those changing their sprockets.

http://gearingcommander.com/

just dug this post up. it looks fairly accurate to what my speedo read out is. i hit 230 at 9000 rpm in 6th on my bike the other week with a 15/43 setup. speedohealer recalled it at 230 and i let off at 9000 rpm, the entire stretch was an uphill section and i just wasnt gonna keep wringing the bike like that but it seems fairly accurate.

Dead thread bump. Just found this jem of a site. Pretty effin handy if you ask me.

Agreed. This thing is comparable to a diamond. Someone pointed out this website in some random post too a couple weeks ago. This was the pure reason why I converted to a 16/43, the math speaks for itself.