Friends:

Twice after working on the Weber carb I have attempted to take the bike around the block for a test run. Both times the bike ran, but shortly after the run began the bike started to run on only one cylinder (No. 2).

Inspection revealed no spark. Replacing spark plug fixed the issue. However, new spark plug seems to have developed the same problem.

As you can see from an earlier post concerning timing issues, I was unable to verify the low speed timing due to the mark jumping around so much at low speed. The timing is fine at high speed. John Slocum replied and said that the issue may be voltage at the plug, and to replace the leads. Given the repeated failure of the spark plug, this seems reasonable as a starting place.

Here are the two questions:

1. Has anyone encountered a loss of spark once the bike is warm? What might account for a loss of spark once temparatures on the bike approach running temparature?

2. Inspection of the spark plug leads and the parts manual make it unclear whether the leads are built into the coil. For obvious reasons I have been reluctant to just pull until it comes out, but I did try removing the plug wire from the coil. It wasn't going to just pop out like the usually do. I've never seen a plug hard wired with a spark plug lead before, but there are several things on this bike I haven't seen before. If the leads do come out, how does one get them out without damaging the lead or the coil?

Thanks for the help.

Brett

I had the same issues and converted to Dyna Coils from the stock and the problem was solved. At that point I had decent voltage at the coils and was advised by my dealer to do the coils as they felt the kokusans were weak. As my bike aged I did develop a drop in the voltage in the start circuit. I have now done the upgrade with a relay for the start circuit. It fires off nicely now. I also found my start button contacts were real dirty. If you have a big voltage drop between the battery and fuse block or fuse block and coils then you could benefit from one or two of the wiring upgrades which are very well put forth in this thread of jcslocums.


Also to answer you question #1. Yes, mine would start and run and foul when warmed up. Maybe the voltage out of the stock coils was droping off as they warmed up. Not sure the reason it acted that way.

And question#2. I don't recall how the plug end of the wire attaches. I don't think I ever removed mine. Could it be that they are threaded onto a threaded spike coming out of the wire? It seems I have seen that somewhere.