Why would a 120 mess around with the front?
I have had an nsr's with all wheel sizes and felt nothing bad or worse between them.
What size 120 fron did you use, 60-65-70 profile?
Recentley have been using 125 wide fronts on another machine and felt amazing the side grip was very great with loads of cofidence, didnt slow anything down. Tried 115's which was also good but you all ways felt you were about to roll off the edge and tuck it in, of which i did once.
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