Friday, November 10, 2006
No wonder the right cylinder has no spark...
I had suspected the right coil on the CX500 wasn't delivering enough juice when it was hot. I poked around on the CX500 forums and a few bike shops, and found that there didn't seem to be many alternatives to the Honda coils ($80-$90) except even more expensive aftermarket coils.
Well, I figured the CX500 has a capacitive discharge ignition, most automotive performance ignitions are capacitive discharge as well, and a high performance automotive coil doesn't cost ninety bucks. Also, in a baka moment, some Honda engineer thought it would be a good idea to make the spark plug wire an integral part of the coil. I'd much rather have a wire I can replace if it goes bad without replacing the entire coil.
So I made up my mind to try out a MSD High Vibration coil on the CX500. Started work installing it today. Mounting it was a challenge - it's about twice as big as the CX500 coil, and I wanted it tucked under the fuel tank in a more or less stock location. But eventually I fabricated a bracket that ought to work.
Then I went to make the plug wire. I checked it with an ohmmeter, and its resistance looked way too high. So I took a look at the wire and at the spark plug cap. The plug cap's resistance was around 17 megaohms! I'm surprised the ignition could even fire. I pulled the cap on the other side, and its resistance was much lower. Looks like I found the problem. Luckily, as I didn't feel too good about installing a new wire but leaving the old cruddy plug cap in place, I've got a new pair of those on order.
So was this coil switch a fiasco? Not really. When I'd done my research, I found that it seemed nobody knew if it was possible to run an MSD Blaster coil on a CX500. And I doubt Honda has built any new CX500 coils for over a decade. So it'll be worth it as an experiment to see if I can come up with a new source of coils for the CX500 community... or a warning about something they shouldn't try.
And if it doesn't work, well, at least I'll have a pretty hot coil that I can put on the Dart if I ever want to try an MSD ignition on it.
Well, I figured the CX500 has a capacitive discharge ignition, most automotive performance ignitions are capacitive discharge as well, and a high performance automotive coil doesn't cost ninety bucks. Also, in a baka moment, some Honda engineer thought it would be a good idea to make the spark plug wire an integral part of the coil. I'd much rather have a wire I can replace if it goes bad without replacing the entire coil.
So I made up my mind to try out a MSD High Vibration coil on the CX500. Started work installing it today. Mounting it was a challenge - it's about twice as big as the CX500 coil, and I wanted it tucked under the fuel tank in a more or less stock location. But eventually I fabricated a bracket that ought to work.
Then I went to make the plug wire. I checked it with an ohmmeter, and its resistance looked way too high. So I took a look at the wire and at the spark plug cap. The plug cap's resistance was around 17 megaohms! I'm surprised the ignition could even fire. I pulled the cap on the other side, and its resistance was much lower. Looks like I found the problem. Luckily, as I didn't feel too good about installing a new wire but leaving the old cruddy plug cap in place, I've got a new pair of those on order.
So was this coil switch a fiasco? Not really. When I'd done my research, I found that it seemed nobody knew if it was possible to run an MSD Blaster coil on a CX500. And I doubt Honda has built any new CX500 coils for over a decade. So it'll be worth it as an experiment to see if I can come up with a new source of coils for the CX500 community... or a warning about something they shouldn't try.
And if it doesn't work, well, at least I'll have a pretty hot coil that I can put on the Dart if I ever want to try an MSD ignition on it.
Labels: Motorcycles
