engine running rough

[legstoshort]

HI EVERBODY.
An up date about my engine problem.
When I was checking things on engine, I noticed when I pulled number one spark plug lead of that engine did not stop or start missing,but when I was putting lead back on, when I put cap near to spark plug the engine ran better, and the same thing with number two plug lead.
I have checked timing a lot times and still same happens.
Any ideas,
P.S when I pull number three and four plug of engine stops.

[HawkeyeGL1200]

I'm not sure what is causing your trouble, but #1 & #2 share a coil. So, the first thing I'd look into is the electrical connection going to that coil, since the #3 & #4 coil seems to be firing okay. It could be a bad coil too, I suppose...

[ct1500]

Your spark plugs are fouled either from a too rich condition or oil usage on the poor running cylinders.

When you make a spark jump it requires more voltage to bridge the air gap and the extra voltage in turn is bridging any foulness of the plug. If plugs are not black or fouled then you need to start investigating high resistance in those secondary plug wires or a weak coil as cyls.1 and 2 share a common coil.

Swap coil with the other and if problem follows coil you found your culprit.

[castlewing]

Hi, I've just been looking at the wiring diagram and it seams that there only a handful of options for the fault you describe and all can be diagnosed using parts already on the bike. Coils have already been suggested, but it may also be worth checking the condensers too, simply swap them over and check the result, take care to discharge them first as they can give you quite a bite if you ain't careful. Obviously check the connections between the points and coils for corrosion and run a multi meter on the wires to check for continuity through the circuit (bike switched off). One other thing although its unusual for both leads on a coil to suffer, check that the suppressor cap has a good contact with the HT, simply unscrew the cap and trim about 5mm off the end of the HT lead and then screw the cap back on. And just out of interest, where in Donny are you, if don't mind me asking?