GPZ550 A1-A4 1980-1983. GPZ550 D1 1981. KZ550 A 1980-1983. KZ550 C C1-C4 LTD 1980-1983. 2x Inner fork Bushes. 2x Outer fork Bushes. The answer is easy, Pyramid Parts Oil seals are all Low Stiction (low friction) seals designed specifically for motorcycles.
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