Is the f3 rear wheel 4.5 or 5 inches wide?

 

It is 5.0 inches, the F2 uses a 4.5 inch rim and the 600F4/F4i use a 5.5 ( so does the 600RR)

 

so whats the largest size tire that can be put on a 5" rim?

 

i had a 190 on mine but now i use a 180 alota people on here will tell u differnt like handling and turning its not that bad my bike turns nice with a 180-190 all depends how u ride also the back rim is 5inches wide and the 900rr back wheel wont fit its 5.5inches wide hope this helps