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But even a bench sync should be able to maintain some kind of idle no?

it should idle he does good work, but one never knows? maybe look for air leaks, hoses, boots, carbs should be top notch if Hunt did them so its prolly something like that, hows compression? and how is your timing? how about valve lash?

also are you positive its fuel related and not spark? could the spark be weak at low RPMs? how is your charging systems and wiring in general? all cleaned up and packed with grease? how bout your coil sticks are they solid and putting out spec?

I'd try to isolate fuel or spark then work form there eliminating, back of the manual might help there?
 

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Discussion Starter #25
it should idle he does good work, but one never knows? maybe look for air leaks, hoses, boots, carbs should be top notch if Hunt did them so its prolly something like that, hows compression? and how is your timing? how about valve lash?

also are you positive its fuel related and not spark? could the spark be weak at low RPMs? how is your charging systems and wiring in general? all cleaned up and packed with grease? how bout your coil sticks are they solid and putting out spec?

I'd try to isolate fuel or spark then work form there eliminating, back of the manual might help there?
The manual is on its way. It may be no help but when I used my water bottle test tank it was idling perfectly which makes me think pump tank or wiring ??
 

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Discussion Starter #26
it should idle he does good work, but one never knows? maybe look for air leaks, hoses, boots, carbs should be top notch if Hunt did them so its prolly something like that, hows compression? and how is your timing? how about valve lash?

also are you positive its fuel related and not spark? could the spark be weak at low RPMs? how is your charging systems and wiring in general? all cleaned up and packed with grease? how bout your coil sticks are they solid and putting out spec?

I'd try to isolate fuel or spark then work form there eliminating, back of the manual might help there?
Also I dont remember the hose barbs on the back of the tank I know one of them is a vent but not too sure about the other
 

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one is vent one is cap overflow..

if it idles with a remote fuel supply then check petcock, pump, pump wiring and fuel line
 

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Discussion Starter #28
one is vent one is cap overflow..

if it idles with a remote fuel supply then check petcock, pump, pump wiring and fuel line
Kind of weird but I think I figured it out. It may have needed the breather hoses to be connected and be below the tank? Made it idle fine after that. The throttle seems to be a bit laggy coming down from a rev and idle is in-between 1500 and 2000 some times changing a little. Is that normal? Or are the rpms on these normally spot on? Also wanna say thanks for helping a newbie like me its slowly making itself back on the road lol 🤙🏽
 

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Discussion Starter #30
RPM's should drop right away, maybe a lean condition, check for vacuum leaks, what you set the air/idle at?
I did not touch anything on the carb since chris told me it should be a slap on in go (at least rideable) ill get a video of it
 

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I did not touch anything on the carb since chris told me it should be a slap on in go (at least rideable) ill get a video of it

ah yes then the lean condition most likely is not carb related, maybe a leaky hose, boot, you have the air filter in and sealed right? all your float hoses plugged in?

spray some ehter around suspect areas see if it idles up?
 

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Discussion Starter #32
ah yes then the lean condition most likely is not carb related, maybe a leaky hose, boot, you have the air filter in and sealed right? all your float hoses plugged in?

spray some ehter around suspect areas see if it idles up?
You might be onto something with the float hoses. Are those the two hoses that join into one hose and go to the air filter? I couldn't find the rubber t's that were supposed to fit in between the carbs so I used one from a later model and they fit the carbs nice and snug but didn't fit the hose that great....
 

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Discussion Starter #34
yup, those
So I made those more snug and re-seated the rubber boots to the carb and the rpm is fine until it warms up, then it jumps to 2k-3k unless i lower the idle with the idle knob then i can get it back to normal idle. But with one blip of the throttle it goes back up? Here's a video of whats going on.

 

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seems to me it runs OK, not the best running I've ever heard but it runs pretty good really, check your choke system, everything from the plungers to the rail to the cable to lever, make sure its free and snaps back and seals, there are o-rings on the caps to seal out air, do not tighten to much they will break and cost $17 each, yes they should be metal..

these CV's have a fast idle circuit on the left control, typically you use that when cold, then when it warms up it will idle normally..

check your throttle cables and linkage for same thing, stickiness, and returning to the same spot on release, is your return cable adjusted properly?.. one cable lifts, one cable returns...

go through the factory pro steps for lean condition then check all this, and make sure you have no vacuum leaks anywhere, you can remove petcock vacuum hose and plug nipple with your finger to see if that changes the idle?

cut ends off any vacuum lines so the seating is fresh and tight.. replace any nipple caps.

the slight roughness may be a vacuum leak? if you cannot find an external vacuum leak you may have to go through the carbs, if just one air idle screw o-ring is gone it will create a lean condition, its an old bike that rubber goes, if all your diaphragms are good you're lucky you may just need a rebuild kit? I'd go through em myself if its not external or the air idle o-rings, you can go to ronayers.com look at microfiche to see exactly what order the o-ring, washer, spring, and screw go.. those lil' o-rings can get stuck in the seat a lot easier working on em with rack off the bike, I dig em out with a tiny hook at the end of a safety pin when they wont come out.
 

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also pay attention to the order of washer spring and o-ring if you do check those o-rings, if anything is missing or in the wrong order that's an indication of the type of rebuild may have been performed, wont be hard to pop bowl caps off and check float height if you remove the rack as well, I think a float misalignment can create a lean condition as well? just gotta chase it down no choice, these things take time, be patient and take the time, may take a few days? it has to be something..

you tried ehter right? maybe a manifold warped or boot cracked? if a manifold warped you can use sealant, if a boot cracked you can use epoxy, obviously new is better..
 

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Discussion Starter #38
seems to me it runs OK, not the best running I've ever heard but it runs pretty good really, check your choke system, everything from the plungers to the rail to the cable to lever, make sure its free and snaps back and seals, there are o-rings on the caps to seal out air, do not tighten to much they will break and cost $17 each, yes they should be metal..

these CV's have a fast idle circuit on the left control, typically you use that when cold, then when it warms up it will idle normally..

check your throttle cables and linkage for same thing, stickiness, and returning to the same spot on release, is your return cable adjusted properly?.. one cable lifts, one cable returns...

go through the factory pro steps for lean condition then check all this, and make sure you have no vacuum leaks anywhere, you can remove petcock vacuum hose and plug nipple with your finger to see if that changes the idle?

cut ends off any vacuum lines so the seating is fresh and tight.. replace any nipple caps.

the slight roughness may be a vacuum leak? if you cannot find an external vacuum leak you may have to go through the carbs, if just one air idle screw o-ring is gone it will create a lean condition, its an old bike that rubber goes, if all your diaphragms are good you're lucky you may just need a rebuild kit? I'd go through em myself if its not external or the air idle o-rings, you can go to ronayers.com look at microfiche to see exactly what order the o-ring, washer, spring, and screw go.. those lil' o-rings can get stuck in the seat a lot easier working on em with rack off the bike, I dig em out with a tiny hook at the end of a safety pin when they wont come out.
Sorry I may have failed to mention this but everything inside the carb is brand new. Jets diaphragm, needles etc all either oem or performance stuff. I will check for vacuum and throttle return and basically everything except the carb because I'm terrified of them lol. I'll see what results I get with messing with the vacuum line and let you know. Im so close rn I took it for a ride up and down the street and everything around it is cherry haha
 
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