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Discussion Starter #1 (Edited)
Here is a pic of my right cylinder..
I am marbled
I have backed out the air mix screw at least 2.5 turns
I tightened up the cover bolts

whats my issue and what do i need to do???
 

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Here is a pic of my right cylinder..
I am marbled
I have backed out the air mix screw at least 2.5 turns
I tightened up the cover bolts

whats my issue and what do i need to do???
It looks like the bike is running very lean. Remove the plug and read it. If it's white it is too lean. The plug should be tan or light grey. If the plug is black the engine is running rich. Running rich will cause bluing further down on the pipe. Running lean the pipe will blue near the cylinder.
 

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^ +1... That's very lean. I have some slight bluing but not clise to yours. Things I would check before I fired her up again is just where are your pilot screws set at? If the covers are still on them, just pop them off and adjust them to 2 1/2 to 3 turns out. Being that lean can cause burnt valves and pistons, I would think. Plus loss of power and running hot.
 

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Discussion Starter #4
just to be clear.. 1 turn is a full revolution of the screw.. so set the screws all the way in until they start to seat and then back out about 2 1/2 to 3 turns...true??
 

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Discussion Starter #5
i also noticed tonight some of the lovely popping on a high rev while parks i.e 4500rpm-ish.. didnt know if that could be related
 

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Linkmeister Supreme
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just to be clear.. 1 turn is a full revolution of the screw.. so set the screws all the way in until they start to seat and then back out about 2 1/2 to 3 turns...true??
You got it Dave. :smiley_th
Put 2 different colored marks 180* opposite each other on the screwdriver handle, near the blade, to make counting revolutions easier.
 

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Discussion Starter #8
BINGO!!! looked at the right cyl and those plugs were snow white..checked the left as well but they were maybe slighty lean but not much.. readjusted both mix screws.. i believe when i changed plugs a couple of weeks ago and moved the screws then, i was either not moving the screw on that side when i thought i was or counted 1/2 turn as a full turn (dumb noob) anyway.. they are out 3 full turns now.

How long should i ride and re-check the plugs to see if my mix is ok??
also..on my other note...popping at high idle revs?? 4500-5000.. i would notice the tach slightly jump with the pops.. what might be going on there

i'm gonna try to get some blue-job or some such today at Wally World(if theyre open) wadding polish didnt cut it

oh well....Happy Easter fellow Vulcanites
 

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First of all, what are you using for air filters? Non stock "high flow" air filters will lean out the mixture, and you will need to rejet for them. The pilot screw only controls the mixture at idle, it will not correct a lean condition at higher rpms. A richer mixture at idle WILL help a lot with backfiring on trailing throttle (slowing down with the engine in gear clutch out throttle closed). I have all ways checked plugs by starting with new plugs, putting a 100 miles of combination highway/city riding on them, then reading them. Yes, you can go through a lot of plugs like that, but the plugs are still perfectly usable. When you finally do get it right, you will have a lifetime supply of plugs.
 

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BINGO!!! looked at the right cyl and those plugs were snow white..checked the left as well but they were maybe slighty lean but not much.. readjusted both mix screws.. i believe when i changed plugs a couple of weeks ago and moved the screws then, i was either not moving the screw on that side when i thought i was or counted 1/2 turn as a full turn (dumb noob) anyway.. they are out 3 full turns now.

How long should i ride and re-check the plugs to see if my mix is ok??
also..on my other note...popping at high idle revs?? 4500-5000.. i would notice the tach slightly jump with the pops.. what might be going on there

i'm gonna try to get some blue-job or some such today at Wally World(if theyre open) wadding polish didnt cut it

oh well....Happy Easter fellow Vulcanites
You should get a new reading in 30-50 miles of combined driving. I wouldn't be reving my engine to 5000 rpms at idle.
 

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Has the exhaust been modded any? A non-stock exhaust could also be a cause of running lean. If so the carbs might be in need of re-jetting.
 

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Discussion Starter #14
i have drilled the baffles...four 1/4" holes each side. I read up on the drilling out and didnt see anything on needing to re-jet afterwards. i believe i have solved it with the correct mix. they are out 3 full turns now and they were nowhere near that far out before i checked. i'll give it another couple of days rides and check the plugs again
 

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general rule of thumb.. exhaust mods=no rejet needed, just adjustments, intake mods generally need new jets, both intake and exhaust mods.. have to rejet.
 

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when i say 'at idle' i mean in neutral at park while ive been checking things
" At idle" means exactly that. In neutral, no load on the bike,at recommended 1100-1200 rpms. You should be concerned how the bike runs in this example. To run the bike to 5000 rpms "at idle" with no load on the engine is only putting undue stress on the engine and won't tell you much. One way to tune a bike at higher rpms is to put it on a dynamometer which places sufficient load on the engine to simulate the bike going down the road. Then you are able to tell how it's running at 5000 rpms. Or you can ride the bike at 5000 rpms and see how it sounds and feels. 5000 rpms at idle is not the way to do it.
 

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True about not having to re-jet with most exhaust mods, and I just a new guy here, but I think I remember reading if the Goat was remove that re-jetting was a good ideal. Or is my memory failing me again?

Anyways we got a very lean condition and just got to figure out what is causing it. Air box /filter problem or partially clogged jets maybe?
 

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Been thinking, dangerous for me, that maybe the lean condition could be cause by a loose boot from carb to the cylinder, or the boot has a hole or tear in it. Just things to check, but the pipes shouldn't be that blue. The guy that I got my bike from completely gutted the exhaust, but did leave the goat on her. I got some after market internal baffles because it was loud. Don't like loud. But still I have a bit of yellowing on the front pipe. The last 600 or 700 miles I've had Sportster mufflers on her. Nice and quiet plus some back pressure. I know it isn't stock, but it's lots closer that what I was running.
 
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