My 21 has a cbr 600 front wheel. The nsr disks bolt right on. The hub looks the same as the stock 21 wheel. I'm running Pirelli slicks 120 in front and using the stock rear rim with a 160. I know this is not the best set up i would like to find a rs250 rear wheel at some point. I've done 3 trackdays on the bike and I think it handles just fine.
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