[Bucky]

A little history on the situation

The bike (2005 Speedmaster 865) was running rough on the right side last Fall. Winter came fast & furious, and so I ran out of riding weather. Salty roads and snow kept the bike in a remote unheated garag e, with the problem un-fixed.

Come Spring, I put fresh gas in her, and went back to right side rough running. In the process of trying to swap plug wires, I discovered one plug wire's copper connection was broken at the coil side. It was on the left / good side though. (Weird.) And so changing the wires side to side didn't happen due to the bad wire.


I pulled the carbs and discovered one diaphragm was slightly outside the track, which may have created a vacuum leak.

I fixed the diaphragm, installed new Magnecor plug wires, installed new plugs, checked the primary side of the coils at 6 ohms each, and now I get no spark on either side.

An inspection with a bright lamp reveals no apparent unconnected wires, (but who knows?)

I could use some advice of a serious nature on how to troubleshoot the problem

Thanks

 

[RedBird]

Do NOT check for spark on these engines by pulling a plug wire and turning over the engine and looking for a spark jumping to the head like we did in the '60's. On these ignition systems, one can cause coil failure and/or igniter failure.

1. Check the battery wires for tightness and cleanliness at the terminals.

2. I would probably purchase a pair of coils or try to get a couple from a dealer off a wrecked bike. I have never in my life been successful testing a coil--auto or bike. They don't fail according to any book or manual. I could tell you a long story of a failed auto coil on my auto that saved a service station owner from purchasing a $18000 Sun Diagnostic machine back in the early 70's.

3. I have read more than a couple of threads about 270 degree twins losing spark on one side. I can't remember the solution, but I think a couple of riders traced the problem to the igniter which costs around $500.

Wish I could be of some help, but I haven't worked on or rode a 270 degree twin.

 

[Bucky]

All is now well
Thanks

 

[propforward]

That's cool - what did you find out?

 

[DN]

Bucky, what was the problem. You're leaving us hanging...