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Discussion Starter #1
my bike (a '75 cl360) has been idling on one clylinder and i suspected it was the coil or spark plug wire. so i replaced the coil and plug and i've got good spark but still it won't idle on that cylinder. the bike runs fine, both cylinders work when i'm moving but at idle... any suggestions would be mucho appreciated. type slowly because i'm mechanically retarded.

thanks!
 

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You are probably looking at a fuel delivery issue or a vacume leak. Start the bike and idle it, use a squirt bottle to squirt water near the carb boots where they join the head and carb, spray on the carb as well. See if this causes the bike to run any diffrently, If it does you have a vacume leak. If it is a fuel delivery problem you could try adjusting your carbs or take them apart and clean them out.

Hey someone pas me the wrench........ Ahh screw it where is the torch
 

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You are probably looking at a fuel delivery issue or a vacume leak. Start the bike and idle it, use a squirt bottle to squirt water near the carb boots where they join the head and carb, spray on the carb as well. See if this causes the bike to run any diffrently, If it does you have a vacume leak. If it is a fuel delivery problem you could try adjusting your carbs or take them apart and clean them out.

Hey someone pas me the wrench........ Ahh screw it where is the torch
 

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Discussion Starter #4
sprayed water on the carb to no effect.
adjusting the air mixture screw has zero effect. (since i can't really adjust it where should it be approximately? i've got it at 2.5 rotations out is that anywhere close to where it should be?)
i removed and cleaned out my carbs about nine or ten months ago, do they gum up that fast?
 

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Discussion Starter #5
sprayed water on the carb to no effect.
adjusting the air mixture screw has zero effect. (since i can't really adjust it where should it be approximately? i've got it at 2.5 rotations out is that anywhere close to where it should be?)
i removed and cleaned out my carbs about nine or ten months ago, do they gum up that fast?
 

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sounds to me like a clogged pilot jet or pilot air passage but i'm no cb wizz. these passages are what feed air into your engine with a closed throttle with enough velocity to atomize the fuel. the mixture exits in front of the needle jet. the holes are so small that many people don't even realize they are there to begin with. use carb cleaner and carefully wiggle one strand of a copper wire to dislodge the gook (wire brush steel wire or ss safety wire is too big and steel being harder than aluminium will likely damage the shape/size of the hole). blow BACKWARDS with compressed air only if you need to. i like to use the carb cleaner (with straw ) to back blow the passage (the straw pointing down through the top of the carb with the slide removed). use a bright light and a lupe (magnifying lens) to confirm there are no blockages (shine down through the top and look into the back of the carb into the little holes). the pilot jet is easy to to remove, clean, inspect (as above), and re-install. hope this helps...please let us know how you're doing.
parks
ps if you can switch carbs easily and the faulty cylinder switches sides, you know it's a carb problem and not an ignition problem...the bad side will display a wet plug after a minute or two of idling on one cylinder.
 

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sounds to me like a clogged pilot jet or pilot air passage but i'm no cb wizz. these passages are what feed air into your engine with a closed throttle with enough velocity to atomize the fuel. the mixture exits in front of the needle jet. the holes are so small that many people don't even realize they are there to begin with. use carb cleaner and carefully wiggle one strand of a copper wire to dislodge the gook (wire brush steel wire or ss safety wire is too big and steel being harder than aluminium will likely damage the shape/size of the hole). blow BACKWARDS with compressed air only if you need to. i like to use the carb cleaner (with straw ) to back blow the passage (the straw pointing down through the top of the carb with the slide removed). use a bright light and a lupe (magnifying lens) to confirm there are no blockages (shine down through the top and look into the back of the carb into the little holes). the pilot jet is easy to to remove, clean, inspect (as above), and re-install. hope this helps...please let us know how you're doing.
parks
ps if you can switch carbs easily and the faulty cylinder switches sides, you know it's a carb problem and not an ignition problem...the bad side will display a wet plug after a minute or two of idling on one cylinder.
 

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yup what parks said, Parks, you've become awfully noticeable around here. . . .
 

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yup what parks said, Parks, you've become awfully noticeable around here. . . .
 

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secondary jet clog. dont spray your carb area with water. use wd40. if it picks up in speed, you have a leak. wd good. water bad.


really, all the fast guys are starting to hang out here. i might have to leave.



jc

aaron sent my wheel!
 

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secondary jet clog. dont spray your carb area with water. use wd40. if it picks up in speed, you have a leak. wd good. water bad.


really, all the fast guys are starting to hang out here. i might have to leave.



jc

aaron sent my wheel!
 

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If after doing everything parks61 says, it still won't idle then check that the idle speed screw isn't backed all the way out. You need the butter fly open just a little for them to idle. I'd check it before doing what parks61 said but you could do it after too, you'll learn a lot about taking the carbs apart if you do it that way.

Mike O.
 

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If after doing everything parks61 says, it still won't idle then check that the idle speed screw isn't backed all the way out. You need the butter fly open just a little for them to idle. I'd check it before doing what parks61 said but you could do it after too, you'll learn a lot about taking the carbs apart if you do it that way.

Mike O.
 

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idle screw on the side of the carb.

if it runs soothly as you roll on, its probably not that. id pull the jets and check for a clog. make sure both carbs open at the same time.

jc

aaron sent my wheel!
 

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idle screw on the side of the carb.

if it runs soothly as you roll on, its probably not that. id pull the jets and check for a clog. make sure both carbs open at the same time.

jc

aaron sent my wheel!
 

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Discussion Starter #20
secondary jet clog indeed. the first time i removed and cleaned my carbs it took me two weeks to figure it out. this time it took three hours to remove, clean, and re-install. that's progress.

this forum is awesome, i'd be out hundreds of dollars in mechanic's fees if it weren't for you guys.

THANKS!
 
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