Cylinder fires when plug cap is lifted

[paddle]

Hi.i stated my blandit 12 project today and as usual it was coughing and farting about from cold but number one cylinder would only fire when I lifter the plug cap away from The plug then would stop when I replaced it.anyone give me the reason for this please.

[Jaydee]

And check the HT lead for cracks.

[Moosehead]

Check the plugs i have had this problem and after checking coils HT leads it was the plugs.also make sure you are buying genuine NGK and not the copies 

[wsn03]

For some reason no one can explain Bandit plugs are a weird and delicate science. They seem to last 5 minutes, and for some reason no one understands they never recover from being wet. They tend to be the home of all electrical problems (I've had a mk1 1200 from new, 12000 miles and on my third set!)

[wraith]

Mmm, this maybe why I go through some many plugs.

Bike stops running on one cylinder always random, change the plug for another plug runs well, then it does it again etc etc etc, now got 4 sets of plugs that get swapped about each year.

[Gixer1460]

4 hours ago, TonyGee said:

its a bit of a strange one wraith, petrol shouldn't kill a spark plug ! should it ?  

They ain't designed to be excessively wet with fuel though! Rich AFR may be tolerated till they foul but not recommended!

[wraith]

5 hours ago, TonyGee said:

its a bit of a strange one wraith, petrol shouldn't kill a spark plug ! should it ?  

The strange thing is, I can put the same plug back in next time and it works just fine 

Plugs are not wet or black or Sutty they are a nice tan/brown colour. Did put it down to bad plugs but as people have said above maybe a cap problem. 

[paddle]

I have had an issue in the past that not one plug would fire spent days trying to find a problem.A set of new plugs and it was perfect.