Help. FZ1 started to Stutter/Sputter

Went to ride the bike a couple days ago. As soon as the bike started it was sputtering. As I rode it for a couple mins at maybe 20km/hr it was a jerky/shaky ride.
It was reminiscent of how my car felt when one of the spark plugs had gone bad (although the bike was more muted).

So I parked the bike and ordered spark plugs. Today I replaced all four spark plugs and the problem is still there. Btw, the spark plugs I took out were all in decent condition.

Now, I am thinking the ignition coil(s) may have gone bad. Coils are expensive and even if I order them online, they won't arrive for another week or more. So is there something else that could cause the problem I described? Something else I should test that would produce similar symptoms?
 
Hard to say with no further history. Have you had the tank up for any reason? If so it's possible that the fuel line is kinked which is a common problem. Also, if you have one of those temperature laser guns, just let the bike idle for five or ten minutes and check each exhaust header to see which, if any cylinders are cold. this way you'll know which one isn't firing. Another issue may be a dose of bad gas.
 
The tank was never lifted. Don't have a laser temp gun. Saw a video for checking the resistance of the ignition coils on youtube. Does it work in the same manner for our bikes.

I suppose I could siphon all the gas out of the tank and put in new gas. Though I don't have any reason to suspect the gas, since I got it from my usual gas station.
 
I have had issues with spark plug cables/boots coming loose, double check everything is seated well and tight.

Has the bike been sitting a while? Is it possible that you're not getting fuel to a cylinder or two? I would let the bike cool down, then start and a few seconds after starting, see which headers are still cold. once you know that, verify you're getting spark on those cylinders and then you can start looking at carb issues. I doubt its the coils, I think its more likely to be a fueling issue
 
The worst thing you can do is throw money in your bike to diagnose a problem. Get a service manual and begin the diagnoses on what the problem is. Many problems have the same symptoms.
 
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