air/fuel settings

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gearhead65
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air/fuel settings

#1 Unread post by gearhead65 »

I'm finally putting my carbs back together after chasing a mysterious problem. Before I disassembled my bike, the #2 spark plug was much more fouled than the #1 plug. So, I think this has something to do with the air/fuel mixture. Check out these pictures and tell me if you think I need to adjust the pilot screw. They both still have the caps and I don't think they've been messed with, but I think the #2 screw may have backed out enrichening the mixture. Kinda hard to tell, but in the first pic the needle sticks up slightly higher.

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2007 Kawasaki Vulcan 500 (first bike)
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coffee_brake
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#2 Unread post by coffee_brake »

Synch 'em.

Looks to me like the butterflies are far off from each other. That tiny hole should be covered the same amount by the butterfly plate for both, it's not.

This is so far off, I'd bench synch 'em by eyeball before I'd even bother to hook up a synchronizer.
Jenn S.
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2001 Vmax
1992 CB750

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Gummiente
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#3 Unread post by Gummiente »

Good eyes, Jenn. I suspect the #1 butterfly was set to accomodate the different position of the needle. The caps will need to be removed and the screws adjusted (if I remember right, turn them in until they gently bottom out, then back them off 1 1/2 to 2 full turns) and then do the synch.
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#4 Unread post by Wrider »

Gummiente wrote:Good eyes, Jenn. I suspect the #1 butterfly was set to accomodate the different position of the needle. The caps will need to be removed and the screws adjusted (if I remember right, turn them in until they gently bottom out, then back them off 1 1/2 to 2 full turns) and then do the synch.
+1, except the starting position is usually 2.5 turns out.
Definitely knock out the plug and equalize the needles, then synch the carbs.
Have owned - 2001 Suzuki Volusia
Current bike - 2005 Kawasaki Z750S
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#5 Unread post by coffee_brake »

I hear it all the time, but, why do you remove the caps at all if you don't change anything like the pipes or the air box? Do they work loose on their own?

My Honda's a lot more vibey than it was long ago...I was wondering if I should remove the caps....
Jenn S.
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1992 CB750

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gearhead65
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#6 Unread post by gearhead65 »

coffee_brake wrote:I hear it all the time, but, why do you remove the caps at all if you don't change anything like the pipes or the air box? Do they work loose on their own?

My Honda's a lot more vibey than it was long ago...I was wondering if I should remove the caps....
They must. I counted the turns out that they were set at and for the #1 carb it was 3 turns out. The #2 carb was 3.5 turns out. That would explain why my plugs were fouling like crazy, #2 fouling more than #1.

Now I have them set at 2.5 turns out. Let's see how this works.

How do you adjust them from there? I'm not really air/fuel savy.
2007 Kawasaki Vulcan 500 (first bike)
Mods:

windshield, taillight mod

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