spark plug wires (long)
The spark plugs on the old GS are easy to get to and I check them every so often. I was pulling off the spark plug wire and the wire came off leaving the metal clip at the end of the wire attached to the spark plug.
The wires were Mallory high performance wires that I had made long ago. Yellow silicone on the outside, but the inside was that fiberglass with carbon. The same crap that cars use. Doesn't cause radio interference, but is fairly high resistance.
To start at the beginning, my Suzuki came from the factory with points ignition. I soon replaced it with an electronic Dyna ignition. Still uses springs and weights for advancing the timing, but the electronic ignition never has to be adjusted.
To get a hotter spark, I wanted to add the Dyna coils. The original coils had the spark plug wires molded into the coils, so the wires had to be replaced too. I got the "make it yourself wires" from Super Shops. They have been out of business for over a decade, so the wires were pretty old.
Motorcycle Consumer News recommended to get solid core (copper wire) wires. Looking online, I found sets for V8's that cost over $100. I finally saw a set for an old VW Bug that cost $16. I bought them, but they were too long and I had to cut them down. They fit great, look great, and work great. I also got a red set for my wife's VW, but the blue ones on the Suzuki match the stock blue pinstripping on the gas tank.
Supposedly, solid core spark plug wires shouldn't be used on vehicles with computers as it could send stray signals to them. But my old bike says "What's a computer?"