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crank down that main pivot bolt to 225 - 250 inch pounds on a torque wrench then give it a try.sometimes that creaking comes from the removable metal pivot facings on the main triangle body and not the swingarm / facing junction. the main pivot bolt holds it all together like a sandwich, any looseness can cause creaking.download the old 98 manual from the files here in this site and it'll have all the torque specs. that 175 for the cross bolt was later changed to 225 in the k2 literature.OP