The FZ-09’s fork springs are designed for a rider weighing less than ~170 lbs (in gear). If you weigh more and/or ride aggressively on the street or track, stiffer springs are in order. Manufactured by Sonic Springs right here in the USA and available in a variety of rates.
These springs are stock replacement and do not require new spring spacers. Price is per pair unless you order 0.80 kg/mm – you will receive one 0.85 kg/mm spring which is intended to be used in one fork leg with the stock spring in the other. Trust us, it works!
Contact us for assistance in selecting a spring rate and oil weight.