47x17 would put you closer to 75 GI. it's what i run, currently.
well, not if you use 23 x 700c wheels :
http://software.bareknucklebrigade.com/rabbit.applet.html
@nimhbus started
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well, not if you use 23 x 700c wheels :
http://software.bareknucklebrigade.com/rabbit.applet.html