astrosail wrote: No missing parts from the caliper assembly--I have the anti-rattle shim/spring and everything is complete. Master cylinder is aftermarket from eBay, two months old.
The chatter when braking at high speeds is both a feeling through the handlebars and a loud high or low frequency vibrating noise. At low speeds when walking the bike in a parking lot the noise is more of a clinking/spinning sound. While turning at low speeds it almost sounds like one pad is bouncing against the rotor.
Looks like the next thing I should do is measure the runout of the disc. I don't have a dial indicator but I'll do a rough inspection with a pen taped to the fork. Does anyone know about getting an aftermarket disc for the KZ440 if getting a good quality used rotor isn't an option? Is it also possible to remachine the rotor to make it better?
Measuring disc runout on the bike is an exercise in futility. You would need to absolutely lock the front end tight so there is no side to side movement with the front wheel off the ground. If you know of someone that has a truing stand see if they will put your wheel and rotor in it and connect a dial indictor to stand and measure rotor runout that way. You can also dismount the rotor and put it on a flat surface and try to sneak feeler gauges under it, or use a straight edge on top of it with feeler gauges. Very difficult process either way. A truing stand is best option. A motorcycle shop should be able to do this quite easily.
I must ask though, are the pads of high quality such as OEM? Are you absolutely certain the wheel bearings are up to snuff and all spacers are correct and in proper locations? Are the fork tubes installed correctly? Don't forget to check your axel for straightness. A slightly bent axle will give you fits at times.
Rick H.