Anyone know how far you can go down in shims before you need new valves? 4 of 5 valves were tight in the yz i just got (Got hosed on this deal bikes a junker) all intakes way tight and one exhaust tight. Exhaust shim was 182 and two of three intakes were also 182 and one was 190. Am I safe shimming them back into clearance they are all way tight. Thinking of putting the 182 in the 190 slot and getting 175's for the 182 slots. That would put them all in spec is that too small though? Thanks, Matt.