[AZKen]

Did not get feedback on my post re: Backfire. Carb? Exhaust? or a pop somewhere? May or may not be a clue there. Hard start would be a clue. Slow or fast starter turning could be a clue. Hope you didn't put on a custom 3" Dia. air cleaner or some such item? Did we mentioned fuel pump, fuel filter clog, line clog, tank clog or gas cap not venting? Run without cap.

He said all cylinders have 120 psi. Jump timing would probably lower the psi. Compression would be uneven or low.

Low mileage, seems unlikely chain is stretched that much.

I think he will recon the situation as time allows. If it runs on flat land at 50MPH and slows on hills. Gravity may be acting on gas flow or debris flow somewhere. Bad fuel pumps always show up under load/hills.