Working on a 76' 550F that had a 550K engine and carb put in it at some point. Fun project so far, and I'm grateful for any advice you can give to get it road ready.
The bike was hesitating under throttle, and plug #1 was fowling. I checked a bunch of stuff (float level/valve needle seat, coils, wires, air filter, etc.) and it came down to the carbs. Since they came off another bike I figured giving them a once over wouldn't be a bad idea.
This is my first carb rebuild, and I've been using Brian Barnes "HOW TO...Rebuild PD46A Carbs," which has been incredibly helpful. Someone has definitely been inside these before, and I'll have to replace a few bolts which were nearly rounded when I got to them. But everything came apart without issue.
I've completely dissembled the carb and here's the questions I have:
It's a set of PD46A carbs. Specs call for a slow jet of 38. They have size 42 slow jets (see photos), and carb #1 has a slightly different 42 slow jet than the other three carbs. Is the slow jet on Carb #1 mismatched and could it be causing the fowling and hesitation issue?
The first and second photo show the slow jet on carb #1, and the third shows it on carb #4.
Should I change the slow jets to 38, as specs recommend? The bike is a '76 550F with 4 into 1 exhaust, F airbox, and the engine is a 1978 550K (according to engine number 2114154 its a K4). Can anyone speak to how to tune a PD46A carb to 4 into 1 exhaust and a K4 engine? It has 90 main jets to meet specs.
And one final question:
The specs for PD46A carbs also say Air Jet of 130 and Slow Air Jet 150. Where and what are the air jet and slow air jet? I'd like to check those and see if they're to spec or have been changed.
