AtomicMechanic wrote:Hey all! In trying to get my 65 CA77 running I noticed the bike is running very rough and wont hold an idle, it will only run under part throttle and even then its not very smooth, i pulled the plugs and they were very fuel rich so I cleaned them up and tested for spark by manually operating the points and looking at the plug, and what Im noticing is that that every time i activate the points it will sometimes spark at the plug, other times i hear when sounds like a spark in the frame somewhere, is there a way to test the plug wires? Or where or how do I replace the plug wires? Thanks!
First, the plugs being fuel rich, they will always look like that unless the engine is really up to temperature, not just revved up a couple of times. The spark occurring inside the frame sounds like the ht lead has been chaffing on the metal work. As both leads are common to the coil if one is shorting then it will affect both. As for testing the leads there's not really a lot to be achieved, you could do a continuity check by using a multimeter, one probe in the plug cap and the other use a sharp pin pushed though the lead by the coil but that damages the lead. An electrician with a mega could do a high voltage check to see if the insulation has broken down. You might be able to see the leaking spark if you run the bike in the dark. Personally I wouldn't bother. With mine, I cut the two damaged leads off the coil about a centimetre from the coil, soldered on the new leads and then slipped a short length of heat shrink tube over the joints. Even using the the original points I still have a reliable spark.