I like chrome. Especially on a black motorcycle. Not too much, but just enough. I have an '03 America.
A while ago I had bought a rear axle assembly off of ebay. It consisted of the axle, nut, adjusters, drive hub, and brake anchor plate. I had the drive hub and brake anchor plate chromed. Put them on, looked good, no problem....
Then, I scored an already chromed rear Speedmaster wheel off of ebay - from a dealer about 70 miles from home. Cool..
I bought aftermarket bearings and bought new seals, swapped the rotor (original) and put the chrome wheel on the bike. Chrome wheel, chrome drive hub, chrome anchor plate. Looked good. Cool..
I started to hear some strange noises from my rear brakes - sort of a "gronk gronk gronk" at low speeds. If I applied the brake a few times it went away. So I lived with it. I had the rear wheel off one day to do a thorough chain clean/relube and noticed my relatively new EBC pads were worn funny - at an angle. The piston side pad, not the other pad. I removed the pads and checked things over and saw the edge of the worn pad seemed to be hitting the slider that the caliper rides on. I took a file to the pad and filed it down to the edge of the friction material and put everything back together. Took a ride and "gronk gronk gronk" was still there. Hmmmm?
Pulled the caliper and noticed the piston pad was still at an angle. I figured the rear piston was stuck in the bore in the caliper. Put a wooden shim in the caliper and pumped the brakes and found the front piston moving - rear stuck.
Took the caliper off the bike, left the shim between the caliper and front piston, and applied some air pressure to the inlet hole where the banjo bolt goes. The rear piston didn't move, didn't move, then shot out across my garage and came to rest under my workbench, destroying some arachnid condos under there. I retrieved it and examined it. It had some wear "stains", but no actual erosion. So I removed the other piston and it had the same stains. I bought a piston kit from my dealer (expensive!!! for what you get!) and removed the piston seals from the caliper. They looked fine.
I took the two pistons and buffed them off using my bench grinder fitted with buffing wheels... no pits-no lines-no signs of wear. Put all of the original parts back in the caliper but swapped the pistons just to be sure. Bled the system with the wooden shim between the pads and both pistons moved free and easy. Cool...
Now since I had been using sintered pads, I checked my rotor thickness just to be safe. Minimum is 5 mm. Mine was 4.6. I had bought an EBC rotor from brent so now was the time to install it... I also had some new Carbone Lorraine pads from brent so they went on too. All new, eliminate the obvious.
The America wheel has 5 mounting points for the rotor - individual bosses with nothing in between. The Speedmaster wheel has a raised center hub with 5 holes drilled into the wheel itself. Remember this...
I placed the EBC rotor onto the SM (chromed, remember this too) wheel and installed and torqued the bolts. They torqued down fine, but felt "funny". I looked closely at the outer edge of the hub and the rotor seemed to be making contact all the way around. I installed the wheel and caliper and etc. etc. and took it for a ride.
Gronk Gronk Gronk..... What the ???
Pulled the rear wheel back off and really looked things over. The EBC rotor, although flush with the hub on the outside, had some gaps on the inside. The chrome plating was enough to keep it from seating properly and thats why it felt "funny" when torquing the bolts. I removed the EBC and reinstalled my worn out stock rotor. It torqued down more gooder. Gronk, gronk gronk she said. I took the EBC to work and had a machinist trim a few thousandths out of the inside bore. Removed wheel, swapped rotor, and as I torqued it down, a line appeared radiating outward. The EBC rotor was cracked. Hmmmm?
Removed EBC, reinstalled worn stock, took ride, gronk, gronk, gronk. I called my dealer, and ordered a new stock rotor - SM and America are the same. New rotor came in, removed, etc. etc. and installed new stock rotor. Gronk, gronk, gronk. Sigh....
Removed wheel, looked at caliper and noticed there are 2 nubbies (that's a technical term...) on the slider portion of the caliper, the part with the pins that the caliper slides on. They were shiny. They had been riding on the brake rotor. And eating it up, I might add...
Now my 55 year old brain was totally addled. What the ****** is going on here??? Then I had an epiphany, a moment of clarity....
The amount of distance between the brake pads and the rotor when you release the brake is minimal - thousandths, if that. I had layers of chrome - on the wheel, on the brake anchor plate, that had moved that center of brakiness, essentially eliminating the needed clearance. That is where Gronk lived....
The rotor has recesses meant to go to the outside - for the hub and the 5 bolts. I turned the rotor over and put everything back together. Gronk is dead. 1500 miles later all works like it should. Installing the rotor backwards gave me the clearance needed to let the brake caliper slide without hitting the rotor and jamming/heating up the pads.
I post this for the chromeaholics here. Beware the clearance, Clarence.
See part 2 for the further trouble with chrome....
