Ok, so i cant sit here and read 15 pages of posts, but i read the first 3.
I hope that somewhere in the 12 pages i didnt read that things worked out, but if not.... just an idea
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Sounds to me like this guy doesn't want to be embarrassed buy your "old School classic" bike making his new pocket rocket look less gnarly.
The same way when you park your shiny vintage Porsche in the back of a parking lot away from all the cars and then some idiot with a Honda civic with a big wing bolted to the trunk parks right next to you.
I work with lawn and garden products all day.
The other day i dropped a spray bottle of some stuff called "Liquid fence".
Its all natural but it may stain.
Let me tell you, this stuff smells like a bag of a$$holes that just got birthed through a diseased and rotten V-hole. I almost cleared out the whole store with this stuff. Its made with egg solids, garlic and some other stuff i couldn't pronounce.
Buy a bottle and give a few sprays on his handle bar grips and maybe under his seat.
Chances are he wont notice till he gets home and wonders why his hands smell like he wiped with no toilet paper. Not to mention the lingering odor when he sits on his precious ninja.
PS: its fun to talk about and think of great ways to reap revenge, but does anyone actually do anything?
Probobly not. Thats why its fun to think about. Because in our minds there is no consequence.