i have a zxr250 usd front end on my 21
you need top and bottom yolks from the zxr
its quite simple really you get stem pressed out of the nsr yolks and pressed into the zxr ones
the zxr spindle fits straight to the nsr wheel aswell (had to get about 1.5mm machined from one of the nsr wheel spacers)
then you need to sort the calipers
i fitted 4 pot brembos on mine with rvf 400 discs just got a couple of adaptor brackets made to carry the calipers
as for the ignition i fitted that were the helmet lock used to be
probaly sounds more complicated than it is
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