FJ1100 running rough intermittently

[momodasaint]

Hi , I have a 1985 FJ1100. It has been playing up but not all the time.  When it plays up it sounds like one or two of the cylinders is cutting out. I took it to a Yamaha dealer to find the problem. They told me it was the igniter box. so i found a replacemnet box. They said that it also had the same problem. I said I bet that both work and its something else. They said it cannot be anything else. I ummed and ahhd for a few minutes then they said they'd try the wiring loom. So they call the next day and said that its fixed. Guess what the problem was?  A wire that runs from the dash to the igniter box was giving a faulty signal sometimes  therefore the igniter would cut spark to cyl. 1 & 4 thinking that the bike was over revving. Well their solution was to cut this wire. Well, it hasnt played up now for two days .   So if anyone else has similar issues, try this  because apparently Yamaha dealer wasnt even aware that it existed .

[novaraptor]

 "Well their solution was to cut this wire."

Ya know? When professional shops do things like this, it doesn't inspire much confidence in them, at least it kind of makes me nervous...