HARC PRO pipes and the new JHA's are the top pipes in Japan. I have a set of Tyga's, and they are just as good, if not better in performance. You cant find a better deal for your performance with the Tyga's. (maybe because Matt used to work for HARC PRO?)

As for pistons, the older RM125 piston will fit perfect in the NSR barrels (what I used for my overbore). The RM piston is 1mm shorter between the pin and piston crown, though, so you will need to machine the cylinder base down 1mm to get everything to work the same as stock. And if you get the Wiseco pistons, they are DRAMATICALLY lighter than the stock NSR units.
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Paul Herr
'88 FZR4/GSXR/YZF Frankenbike
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