So I bought a motorcycle a couple of weeks ago. For a while I’ve been keeping an eye towards craigslist for a cheap motorcycle, mostly so I could save a little money on gas driving back and forth from work. I’d had an interest in the 1970’s Honda CB series, which was a prime choice for cheapness, but after seeing a Honda CX in person and realizing that they are water cooled and shaft driven, ( which equals longevity and potentially less maintenance) I included them in my notice list. I’d kind of set an arbitrary price limit at $500. A non-running CX showed up on craigslist for $400, and while I was mulling it over, another showed up for $180. Thinking it would get snatched up quickly since CX’s are quickly becoming a target of folks doing “cafe racer” conversions, I called the guy and went to get it.

1980 Honda CX500
I think it was a little more ratty than I had expected, but in reality, it’s not bad at all. The guy bought it for a project but found a running CX before he got around to working on this one. Word from the person he bought it from was that the CDI box was dead. I talked him down to $120 and took it home.

Tank and seat off
I’ve been slowly picking it apart to make sure that the CDI is indeed the problem and see if anything else needs to be done. Short of an open resistor in one of the plug boots, everything is seeming ok. I was lucky enough to get in on a group purchase for the Inigtech CDI replacement box through www.cx500forum.com. These units seem to be the only drop in replacement for the OEM CDI boxes, and a lot of CX riders are using them successfully. Shipping from the Czech republic is a little spendy, but when you figure that this will last a heck of a lot longer than a 30+ year old used CDI (including a 2 year warranty) AND give you the ability to program your spark curves, it’s kind of a no-brainer.
I also made the decision to send the carbs out for rebuilding rather than do it myself. I’m no stranger to freshening up carburetors, at one point I could do a Quadrajet in about 15 minutes, but these Keihin units appear to be a bit more complicated, and my free time is pretty limited. After crawling around honda motorcycle message boards for a while, I found that Larry Cargill, the guy who literally “wrote the book” on working on these carbs also did rebuilds. I saw a lot of his procedural photos, and realized that even on my best day there is no way I could be that thorough. He sonic cleans everything and reopens the jets and passages to OEM sizes down to the thousandth.
Once I get these two pieces on and the engine running, I’ll have to give the brakes a little attention. The front brake master cylinder is trashed. I ordered a cheapo master cylinder and lever from ebay for $25 that should be plug and play. Hopefully autozone can turn the rotor.