I’ve made some progress on my CB550 since my last post, and this entry is part of my effort to document all the changes. It’s been a fun and challenging process working on this thing, and I'm learning a lot already, thanks to the collective knowledge in this forum. Ok, on to the changes...
Front BrakesThe front brake pads were wore down to nothing when I got the bike, so this maintenance definitely had to happen before I could take the bike out on the road. I ordered some ‘organic’ pads vs. the old school asbestos ones, so we shall see how those work. First problem out of the gate: one of the old brake pads was stuck in the caliper. After a number of unsuccessful tries to get it out, I finally figured out that I could drill a small hole in the middle of the old pad face and insert an eye hook. I then was able to grab the eye hook with a pair of channel lock pliers and pull it right out.
Eye bolt used to remove stuck brake pad
I then discovered that the piston was really stuck in the other caliper. I learned through this forum that the best method to remove a stuck piston is to simply use the actual braking mechanism to force the piston out of the caliper. I unfortunately did not learn this until I had disassembled the line and drained the fluid, but hey I'm a newbie and this is part of the learning process!
Once I got the piston out, I could see why it was difficult to remove: it was rusted and corroded, as was the brake pad casing. The shop that had supposedly rebuilt this front brake unit only a couple of years ago did not use the proper lubrication, and they also assembled one of the mounting bolts so that the fender was installed crooked. There was some tar-like goo on the left fork, which I suspect was the wrong kind of lubricant melting from the extreme heat. And the rust you see here is likely from the exposed metal parts touching directly along with moisture contact.
The result of a poorly installed and maintained brake system
Once I got all of this apart, I thoroughly cleaned everything and started to put it all back together. I very lightly sanded the inside of the caliper and the sides of the piston to remove the rust, then cleaned everything up with brake cleaner. Just as in woodworking, I did a ‘dry fit test’ first to make sure that everything would fit properly. I discovered that I needed to file down the new brake pad casing just a wee bit, especially around the tubular pin notch at the top, in order to get it to fit into the caliper without binding. I made sure these exposed parts were lubed to avoid rust and direct metal contact. Thanks to Two Tired and MotoBunnY here in the forum for their tireless effort to teach the gospel on proper brake caliper assembly using the right lubes in the right places.
New brake pad dry fitted into caliper
I found some of the fancy Dow Corning Hi Vac grease that Two Tired recommends at a local science supply shop here in San Jose. It was a bit overpriced, but I decided to pick it up anyway.
Reassembled brake system
Once I got everything back together, the not-so-fun part was ‘bleeding’ the brake lines to try and get all of the air out of the system. This was definitely a trial and error process. I had an epic disaster when I learned the hard way that brake fluid will take off paint and paint finish in no time flat. I ended up spilling some on the tank when I was trying to unclog that tiny bothersome hole in the bottom of the master cylinder. Fortunately, I am planning on having my gas tank painted so the damage you see in the pic below is no big deal. But definitely a major note to self for future brake fluid maintenance.
DOT 3 brake fluid makes a wonderful paint remover :-(
I eventually got all the air out of the system, adjusted the front brake tension spring, and it's worked like a charm.
Rear BrakesI was able to disassemble and replace the rear brake shoes using the center stand without too much work. Probably the hardest part was getting the wheel back on and aligning it without an extra pair of hands!
New ExhaustMy bike came with the four original stock exhaust pipes, but I decided to replace them with a Mac 4-into-1. This was a pretty straightforward process, and I had the new pipes on in no time.
My new 4-into-1 exhaust set, ready for installation
Rusted exhaust flanges cleaned up and ready for re-install
Old exhaust pipe gasket on the left, new one on the right
I checked the spark plugs before firing it up with the new exhaust, so that I can monitor any changes over time. They looked pretty normal, or maybe slightly on the 'rich' side of things, and all four were consistent. I’ll see how this new setup runs, and make adjustments as necessary - rejetting if I have to.
As has been noted numerous times in the forum, one of the unexpected results of having this new 4-into-1 exhaust system is that it allows the center kickstand of the bike to retract too far toward the frame, resulting in the stand rubbing against the drive chain. This is because original single pipe no. 2 had a small rubber foot that kept the stand from swinging up too high. The extra 'L' bracket that comes with the Mac 4-into-1 set is supposed to mount on the frame and extend down to work as a stop for the center stand. If you mount it to the rear foot peg it does do that, but there are two problems. One, the stand rattles against the bottom of the bracket when you hit rough road. Second, the chain bounces up and down during driving and so the gap between the center stand and top of the chain needs to be pretty wide in order for the chain not to hit the stand anyway. After some research, I opted to remove my center stand altogether, and will use it only when needed during some maintenance. I'll probably regret that the first time I have a flat out on the road. Then again, in order to get the rear wheel off during roadside maintenance I would need to have a decent set of tools on hand anyway.
Custom Tail LightI decided to replace the original big honk’n tail light with a smaller, more streamlined version. This turned out to be more of a challenge than I thought, but it ended up working out just fine. I had to drill new holes in the chrome fender, which I was able to do with a standard metal drill bit. I located the holes using the new tail light base as a template. I then used a small punch to start the hole, and used a bit of blue masking tape to help protect the chrome surface around the spinning bit.
The original tail light had three wires, but the new one only has two. I figured out that the third wire was a ground, and so a I added a ground wire from the internal light casing that connects to the third green ground wire from the bike. Until I did this the tail light would not even come on, because the rubber base between the new light and the fender did not allow any metal to touch and so nothing was able to ground out. Once that third wire was connected, the new tail light and brake light worked like a charm.
New ground wire added to the internal tail light casing
I had to remove the wiring temporarily from the wire channel on the underside of the rear fender so that I wouldn’t damage anything when I drilled the new holes. I found that an excellent way to re-feed the wiring through the narrow channel is to use heavy duty picture hanging wire as a ‘pull wire’.
Heavy duty picture hanging wire wrapped/taped to electrical wire in order to pull it through narrow fender wire channel
And finally…
The finished installation
Turn Signals and MirrorsPurists here need to cover their ears. For now, I have removed all the turn signals and mirrors. I’m kinda digging the look of the bike without them (this is the cafe race side of me talking), but will continue to contemplate adding the smaller ‘bullet’ style signals later on. I will be replacing the handlebars very soon, at which point I will likely install custom mirrors that attach to the ends of the bars rather than attaching vertically on top.
Custom SaddleAnd finally, I located a second seat that fits my bike (Thanks, Stev-O!). I removed the cover and all the internal foam, then cleaned up the seat pan.
Seat pan after old foam and cover removed
I then sent it to a guy who does a lot of great upholstery work on motorcycles, cars, and even household furniture. He is going to make a seat for me that is low profile with some fancy pants stitching…can’t wait to get it on the bike! The existing stock seat that is on the bike now is in really good shape, so I will most likely keep it in case I decide to sell the bike later on or start another project bike that needs a seat.
Ok – I think I’m finally caught up. While I am waiting for my fancy custom seat to arrive, I think the next project will be to tackle replacing the handlebars….
