In the last 4 years I seem to have had a run of every bike I own having the plug caps shorting out. Carry some wd40 with you, if you get issues, spray it up inside the plug cap, do 1 at a time, and it may quickly isoltate your culprit. I now carry it as standard kit on my 125's and 250, but don't carry tools on the ntv650. It's too complex / awkward to roadside fix. When a plug cap starts playing up, even a bit of damp on the road getting thrown up by the tyres from rain the day before was causing my bike to slow to a halt. Eventually I found after enough treatments at the roadside the wd40 left enough oily residue to effectively cure the issue. Yes I am that bad about ordering spares for my commuter 125, besides a small can of wd40 is cheaper than plug caps and I had issues getting plug caps long enough, kept getting sent short ones.
