Weak spark

[Big Red]

I have a mate who has a R100gs and he has a weak spark on one cylinder. He has replaced the coils, ignition control unit and the trigger unit. He has tried swapping the plug leads from another bike that hasn't made any difference, is it normal to have a weak spark.

One plug gives a blue spark and the other gives a yellow one

 

[DrFarkoff]

One plug gives a blue spark and the other gives a yellow one

What happens if he changes the plugs over?

 

[Rob Farmer]

Does the bone run ok?

 

[Big Red]

What happens if he changes the plugs over?

The same happens, it makes no difference

 

[Big Red]

Does the bone run ok?

His daily ride is a 1200 Super Tenere so I don't know but I will ask the question

 

[Kenny]

Well it can only be either, coil, plug leads and cap ( favourite as they do fail )
Change plug leads/cap over and see what happens then