Peacock to carbs, 1980 550 questions

[Ckowens]

First and most important, the settings on the petcock are to the left a dot, top is pri, right is a dot. What is what, what do they do and where should it be set?

2nd, in any setting will gas flow from the petcock freely? I'm trying to start a process of elimination on why my bike isn't getting fuel. When I do get it started it will die if I don't manually keep it throttled some... Yet I always have smelled gasoline pretty strong when it's running? I know the carbs need tuned up but I'm hoping that it isn't the core problem.

[Ckowens]

Oh, I noticed black smoke last night when I got it started.

[tom203]

If you still have a stock vacuum operated petcock....... in prime spot, fuel will flow at all times; in "on" or "res" spot fuel should only flow when a vacuum is applied to petcock (running engine produces vacuum). normal spot is "on" . Remove the lines and test it out- get some clear vinyl tubing, put on petcock's vacuum fitting and suck- no fuel should show up in this vacuum line.

[Ckowens]

Ok, I follow. So what's the purpose of the prime position and my real problem comes by not being able to destinguish the difference between the left and right positions. They aren't labeled, only defined by a dot.

[barnbiketom]

Prime position is for a bike that has sat long enough for the gas to have evaporated out of the carbs and they are dry. OR if you just rebuilt your carbs and they are dry, Prime will start it quicker.

In Prime.. gas should flow instantly.

in the other TWO positions which are main and then reserve (not sure which dot is which?), engine vacuum turns on the gas flow after it is running. that's what the small hose on the petcock does.
You just want to make sure gas is NOT flowing in the positions other than PRIME.

If it is indeed flowing in prime, and your bike is bogging/surging/running like crap.. then look elsewhere....probably carb internals are dirty and gooked up

[Ckowens]

Ok, now I'm getting somewhere. This is my 1st bike and I know nothing of them but I'm kinda ... Well I should be able to figure a lot out as you guys educate me. I got it in April and have ridden it since until about a month ago when it had to be parked till the chain was replaced. After I got it back it lasted a couple days and then parked again for the battery. After the battery the choke cable was stuck. Now all that's cleared up but it still won't idle right and now I'm having problems getting it running. I know the carbs are off due to the 2 yellowing pipes and one is blueing.

[tom203]

If the bike sat idle before you got it, nasty stuff might have collected in gas tank, then drifted into carbs with a little running. A thorough cleaning is calling to be sure.

[Ckowens]

In fact it did. Though it is well maintained I know it sat for three months without being fired once before I got it this spring. Carb sounds pretty intimidating, you suppose it's something I can do or should I have it done? I'm kinda poor but I miss my bike.

[tom203]

In fact it did. Though it is well maintained I know it sat for three months without being fired once before I got it this spring. Carb sounds pretty intimidating, you suppose it's something I can do or should I have it done? I'm kinda poor but I miss my bike.

Three months ain't long- try a dose of Seafoam (or equivalent) and offer sacrifices; you might get lucky or at least make bike more rideable as you wait for winter. Of course, if PO's had neglected carbs for years, it's your job to clean them properly to avoid frustration. Basscliff's site leads you thru carb cleaning step by step,

[Ckowens]

Lmao, offer sacrifices huh? I found bass cliffs and have been thumbing through it for a couple days. Learning a ton. Says spark plug gap at around .03? Sound about right? Tomorrow I go back to wrenching on it and I appreciate all the help sincerely!

[Ckowens]

Running but no power.

[tom203]

Running but no power.

So it started up, but is not happy when you apply throttle? Did you check for correct petcock operation? Do you have an air filter element installed? It's a step-by-step process of eliminating possible problems- guessing is not recommended.

You sorta implied it had been running OK till chain replacement by someone- did this someone do anything else at the time?

[Ckowens]

Yeah, I've been trying to do step by step. Anyway, here's what I got, today we pulled the air cleaner and it was gas soaked. Pulled the plugs, they were wet too. Checked fire on the plugs and only one was firing. Replaced plugs and pulled filter. Fired and ran like a champ, smoked like hell but it ran great! Idle was good too. Let it run for a few then took it out for a couple miles. Ran great till I got high rpms and then it started getting jerky again. Confusing cause it was purring, but I could feel it stalling out. Got home, still runs, full power, but idles dropped and it dies. Hmmmm.

[Ckowens]

No, the guy who did the chain is a friend who does bikes, didn't even charge me.

[tom203]

You need to discover why gas is overflowing into airbox- bad petcock (or left on prime spot) or carb problem . I'd disconnect petcock lines and check out how well it's working- does it shutoff in "on" spot when engine is not running?