OK, I'm going to attempt to document the list of things done to my bike while at Larry's Scooter Repair and Snake Den. I know I will forget things that were done, but, Larry will fill in what I missed and probably correct a few things as well.
It actually started in my garage where Larry was kind enough to do a quick assessment to make sure it was safe to ride to his garage. Before he even glanced at the ST he began pointing out a few things that needed addressed on my Harley. I followed most of those suggestions and am working the remaining suggestion. By the way, thanks for that, too, Larry!
We were working on the premise that I still had a lot of air in the brake lines and a thorough flush and bleeding would remedy the issue.
The 1st thing that was addressed was the Preload Adjuster. It was removed, inspected and cleaned. We then charged the system with oil making sure to fill the line from the adjuster to the shock and then fill the adjuster. Any air was worked out of the line and adjuster and it was reinstalled. Night & day. Now the adjuster works properly and I know how to do it myself properly next year.
We then moved on to flushing the clutch master cylinder. The Brake fluid was brown and in need of a good flushing. Larry found the boot was torn/disintegrating. Everything was cleaned and reassembled with a new boot and the a good flush and bleed.
I believe we then directed our attention towards the throttle bodies. We made our way to the buggers and along the way discovered the K&N filter oil all over the place. Larry meticulously cleaned everything and marked the parts for position and then proceeded to sync the TB's. They weren't too far off but Larry got all 4 ducks in a row! He then rerouted the vacuum lines than nest down in between the TB's so that they on top and would not collect moisture and junk. When we were reassembling everything, the decision was made to toss the K&N filter and go back to the stock Honda filter.
Now the brakes were in our crosshairs. The master cylinder was cleaned and inspected and we began the bleeding/flushing process. we got a lot of air out of the system and were encouraged. When we made it to the SMC we ran into problems. I had rebuilt it, but, it wasn't functioning correctly. Larry thought that the little filter was clogged, but, kept working at it and after a bit we saw progress. Things were freeing up and appeared to be working correctly again. The rest of the bleeding/flushing process went well. We thought that we had side stepped the problem and began to button things up and take it for a test ride.
While the bike ran great, the brakes were still making the "howling" noise. This was the beginning of what turned out to be a long and frustrating ordeal. After more bleeding and trouble shooting and head scratching we made no progress. On one test ride the rear wheel actually locked up on me for a brief moment while turning back on to Larry's street. It was long enough for the engine to stall, the back end to step out just a bit and then the brake released and the engine fired right back up.
The rear tire was removed to inspect and see what we could see. Well, we found the flange bearings were toast and even spun turning the housing a lovely color. The bearings were replaced. The final drive splines were in need of moly paste but weren't destroyed. Larry cleaned them up and applied the moly paste. The dampers wer cleaned up and conditioned and an incorrect O-ring was found and replaced. We thought that maybe these things were the problem. While they were a problem they weren't contributing the noise.
Larry began to suspect the SMC turned his attention there. He quickly discovered that the front pads were EBC pads and too thick. It was thought that perhaps they were causing the rear brake to drag and that was getting things hot in the back. I believe it was at this point that the decision was made to replace the SMC. We didn't want to just throw Honda pads at it. The fork seals were leaking and had made quite a mess and the forks needed to be addressed before the braked. So, the forks were rebuilt. I ordered a new SMC and when it came I dropped it off to Larry. He got everything reassembled and bled the brakes again. Surely, the problem had been solved!
No, not so much. All that I've described so far took place over several days. There were several more ahead. The noise was still there taunting us, laughing at us, flipping the proverbial bird at us. Larry again went over everything again making sure all was correct. Everything in the front was as it should be and passed every function test flawlessly. This meant the problem had to be in the rear. I don't know how many times the brakes were bled, but, it has to be a double digit number.
As we were staring at the rear caliper, Larry eyeballed something that looked odd. The rubber boot the guide pin resides in on the rear caliper was distorted. We compared it to the one on his bike and it was obviously not right. We removed it and discovered it was not even the correct boot. With a new boot installed and properly lubed the caliper traveled back and forth on the guide pin much easier. We took it for a test ride and discovered that we had made progress. We got about a 50% reduction in the noise as well as the frequency of the noise. This was good encouragement after days of frustration.
Now, Larry was convinced that we had narrowed down the location of the problem. The rear caliper bracket sub assembly was removed so as to get a closer look. We could see that the pin bolt was bent just enough to see with naked eye. Larry marked the stopper bolt and reassembled the rear braked to see if it was making contact with the bracket and where. It was touching on the very end of the top of the bolt and on the bottom it was touching in the middle of the bolt. The bracket was twisted so the caliper was not traveling left and right straight. The caliper was sliding into the rotor at an angle when the foot pedal was pushed. When the hand lever was pulled the two outer pistons would engage and square up the caliper and the noise would go away. That was the theory, anyway. The last thing on the list would have been the rear master cylinder.
It was about 10 days before a new bracket arrived from Georgia. I dropped it off to Larry Saturday morning and was riding it Saturday afternoon! Problem solved. Apparently when my rear brake locked up it twisted that bracket just enough to misalign the caliper causing the "howling" which actually sounded more like a chair being scooted across a concrete floor.
I'm sure I left out a lot and probably gave too much information. Sorry if this is too long, but, I had a lot to say. Larry will have much to add I'm sure.
Once again, thanks to Larry for his invaluable help and efforts!
