Well the CB650 is done. Well. If it belonged to me there would be a lot more that I would do but the owner is happy. He basically wanted me to get it running and then, assuming it ran well, install new exhaust. I had the bike running about a week ago. It ran like crap because the exhaust was all rotted out and I'm sure this was impacting the compression but I thought it would be ok with the new exhaust. So he plunked down $325 for that. It arrived earlier last week and I went to pick it up. There was some mis-communication when ordering the exhaust though. What we got was replacement mufflers. He thought he was getting a full exhaust (including the headers). I was told by a mechanic at the shop that this would work but that I would have to get the mufflers welded on. This did not seem correct to me because the pieces were nice and shiny from the chrome. There were no instructions with the exhaust either. I finally talked with another mechanic and he spent over an hour with me trying to figure out if these would work and, if so, how to make that happen. The replacement mufflers we got will only work on a CB650 Custom and, as I found out, it's very difficult to tell if you have a Custom model or not. Well...I do. In the end, we figured out that in order to make this work we would need to cut the headers off the one piece stock exhaust system. Below is the H pipe that is welded into each side of the stock exhaust. I needed to make cuts in the headers as close as possible to the welds on the far right. I used a pneumatic cutoff wheel. Then the mufflers simply slide on. The trick is making sure you have enough header inside the muffler and, apparently, this will not work with a standard 650.
This is the right side all adjusted and bolted up. You can barely see where the headers slide into the muffler just below the side cover.
This picture makes it look like the mufflers are not even but, if you know me, they are. To the 1/16 of an inch in all directions. The left side was a bit more difficult to get adjusted correctly because of the kickstand and center stand but eventually it came together.
The bike looks so much better with this exhaust and it sounds really nice. I took it out last night for a drive on the side streets through town and saw no less than 3 police cars. The plates are 2 years old but I'm happy to say that I did not get pulled over. It's hard to believe that this bike is over 30 years old and has never had any real work done to it. No valve adjustments, no re-builds, nothing. The carbs have never been removed for even a cleaning. This has been a super fun little project and it's got my gears turning. It might be time to start thinking about a project for myself.