Quoted from AdjustFailure:Well it is a SS Evel, and I did clean the switch contacts with fine emery and contact cleaner, however the suggestion re capacitor does make sense to me, I will check this tomorrow. I had the feeling the root cause was too-brief a signal based on a fast and quick hit and rebound off the switch contact, given that it works otherwise fine with a slower or angled hit.
Inspect the switch contacts closely the gold plating is most likely gone or compromised. Don't use emery on gold plated switch contacts. The most aggressive you can get is a pencil eraser, and most of the time whatever dirt is on a gold plated contact can be cleaned with a business card or other piece of paper.
You still need the capacitor though.