I don't think I've ever changed sparkplug wires on one of my Motorcycle !!!

 

An ohm meter will find high resistance, and firing the bike up at night or in a dark garage will tell you if the insulation is cracked and shorting to ground.

 

Good plug wires are like 35-40$. I've got 25,000 miles on my ride and I've already put new Sumax wires on. My 99 Heritage fried the wires at about 15,000 so it was a no brainer to spend a little on some quality wires.

 

i have a 76 shovel. i needed a plug wire once because the end pulled off of the wire and stayed in the coil. i found a plug wire at my brother in laws trucking company in the parts room that was for a 1962 diamon reo gas tractor. it's still on the shovel.

 

I put the Blue braided HD plug wires on my BadBoy in '98. In 2009 and over
110,000 miles on them I replaced them with some Screamin' Eagle wires
because the engine developed a slight miss. It cleared right up, no more miss!