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The reason I'm concerned is the oil reservior & dampening control looks like it could impact on the frame if I take a little drop off!
Simon - for the nr-4 rub, take an old handlebar grip and cut about a 3/8" (7-8 mm) slice. put the piece on the nr-4 reservoir and slide it up to the top of the spring. you may have to rotate the spring in doing so. set the rubber strip near the top where the top two coils come together. use a little windex or such on the reservoir to help slide the grip piece, the windex will dry and the pressure against the spring will hold it in place.that will prevent the rub and noise that comes with it. OP