As you are only using it for trackdays it wont be getting no where near the treatment it would if it was being raced, so i would stick with the hrc pistons, its not like you will be changing them halfway through a race weekend. All depends how many trackdays a year you do, if not many then a pair should last you. Different when the hrc ones dry up, (like they have for my nf5), but if you intend keeping it for a while it might be advisable to stock up. Another thing i will say though, an RS250 or 125 come to that, is not a bike to be run on a budget. Enjoy it though Cheers Les.
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