Spark plug wires and discolored pipes!

So I have an issue that I guess I should get sorted out. When I changed my spark plugs a couple weeks back on my '03 ACE 750, I noticed that the wire on the forward cylinder (gear shift side) had some corrosion in the boot and it didn't really click onto the plug. I recently noticed the the front exhaust pipe has started getting a slight brown tint to it, so I was thinking that if both plugs aren't firing, maybe there is some incompletely burned fuel making its way into the pipes and burning there causing them to get a bit too hot. First off, does this sound like a reasonable explanation, and on a second note, does anyone have an old wire for that plug laying around that I could replace it with? :lol: I would be willing to pay for it! (Just not Honda price haha)