Topic: CB550 Spark Plug Order

[Uncoiled]

So I have a project 78 CB550 that I am building, and the previous owner put a dyna ignition on. I'm pretty sure he put the plug wires going to the wrong cylinder since 1 and 4 should be off the same ignition and 2,3 on the other correct? Here is a photo of mine, he has 1,2 and 3,4 together.





So my question is, which wire (blue or yellow) is for 1,4 and which is for 2,3.

Thanks in advance!

[LesterPiglet]

H'mm tough choice. Spark the points and see which ht leads react.

[Deltarider]

You may want to check the overall impedance. Aren't those suppression cables?
Normally the coil that is fed by the blue wire, does 1+4, the one with the yellow wire is supposed to do 2+3.
#3 HT lead is touching the head and might loose it's spark there. The others touch the frame. Your HT leads are too long so I would mount those coils 180^o around. That way everything is better shielded against rainwater.
http://oldmanhonda.com/MC/wiring500.html

[Uncoiled]

Thanks! I ended up seeing the blue and yellow while checking the timing and figured it out, once I moved them it fired right up!

I don't know what suppression cables are but eh previous owner installed those, are you saying you can lose spark through the rubber insulation??

[Deltarider]

Yep, in the wet it's possible. I have similar coils and mounted them 180^o around. I wouldn't be surprised if your cables then show just the right length. Unplug the HT leads and use an Ohmmeter to check for total impedance of HTlead plugcap included. There should be around 5KOhm resistance in each HTlead, 10Kohm maximum.

[Uncoiled]

I went to check the timing and noticed the yellow and blue wires going to the points for each set of cylinders. Once I saw that I adjusted the wires to the correct cylinders and it runs! I also turned the wires around so they don't contact anything so hopefully it will negate that issue as well if it were to ever be ridden in the rain.