When I first got my beach cart I forgot to hook up the strap. When I pull the handle up my boat went sliding off into the middle of the road at Crazy Horse campground...
Haha. Done that too, dont feel bad.
I had a crank rebuilt by Crankworks. They forgot to reinstall the collar that the rear seals sit against. This was my first rebuild, so I didn't really notice until the entire motor was completely assembled.
Bought a limiting rope, decided to install it some other day, you get the picture.
Bought a ski from someone at high elevation, brought down to my ride spot without changing a thing. Rode it WOT, you get the picture.
Had my cylinder decked. Rebuilt it without checking compression. Broke in ok, rode it WOT, you get the picture.
I've done several things in the attempt to save money, only realizing that you might as well just spend the money up front. For example. I changed to a 62T motor, decided to have the FPP exhaust mani machined to match the ports. Ran 8mm coils in the cylinder. Spent way more than a manifold would of cost.