Ran perfect for 4.5 miles, then problem returned
I pulled the carbs last night, removed float bowl covers, jets, float valve. Sprayed with carb cleaner, blasted with compressed air.
Put it all back together in the morning, and it was running great, plenty of RPM, no back fires, I was smiling.... drove 3 miles to a gas station, filled up with premium I thought I was home free......
Drove another 1.5 miles from the gas station, and the issue returned, no power about 3K rpm, will rev great in neutral, idles great, starts great.
Limped back home, replaced fuel filter, tested fuel pump (pump tested at about 24 oz/minute within specification)
So I don't know if it ran for a bit because it was cold, and once it warms up coolant is causing an issue? Or if I cleared something in the carbs, and it returned.
Tried Swifty2014's suggestion of parking in a dark spot, sprayed water on the coils looking for arcing, I could not see any.
Problem: No power / backfires / misses above 3K rpm
Adding choke helps a tiny bit, might give me 3.1K rpm
Attempted so far:
Drained fuel tank, replaced fuel with premium.
Replaced spark plugs (Thank you kensanders for the suggestion).
Tested pulse unit with ohm meter (in spec)
Cleaned carbs (did not separate), ran great for 4.5 miles.
Tested fuel pump (in spec)
Replaced fuel filter
Next step is to do a compression check, but I need to get an adapter for my compression tester.