Never seen the kx 89 46mm , we never got them in Australia , only the first up side down.I did ride a 89 rm125 sling shot that had the 46mm fork , it was good , I preferred the forks on the 88 kx 250 over the 89 kx 250 any day . Emulaters gold valves only go in forks that have damper rods, 89 k5 have piston and shim stack which can be replaced with a normal gold valve, if anybody changes to 13 /14 air forks or the new 15 fork , these forks benefit from a new gold valve both mid and compression valve , big improvement , not trying to sell any one race tech stuff , im sure there other stuff just as good out there , I get most of my stuff for suspension from the distributor in aust , at discount prices .