Just getting into this evo racing (pre1990) and need to get the suspension working. Looking at fitting 03 Yam fork internals into the KDX forks. The shock is the sticking point at the moment. It's a remote res unit about 390mm eye to eye so replacements are limited. Porting looks restrictive so was going to cut the res off a WP unit but due to the ratio it needs a fair stroke (100 wheel travel = 46mm shock movement) Race tec don't list valves for the 86. So to the question, anyone know what shock uses a 40mm piston, don't mind a bit of machining/modding. Thanks.