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I don't think you have just one problem
The interesting points so far are:
1: Carbs have been cleaned by running carb cleaner/other solvents. - I believe you have CV or vacume type carbs
2: It runs/ran better with the choke on, and dies when the choke is off
3: It ran better with the idle screw turned clockwise -> which i believe means with the butterfly valves are more open
4: The engine hiccups on the highway, and bogs down in a turn - Left and right turns? or only one side?
5: The engine starts with the petcock in the prime position, but not in the on position. - Had you reset the idle screw back to the original position, or was it still turned clockwise?
Its sounds like you have at least two, possibly three problems
The first is that I suspect the vacuum diaphrams in the top of each carb, which lift the vertical slides and let in more fuel, have either become soft, or one or more has a small leak. This is likely the result of a little too much carb cleaner being sprayed through the air intake, which softens the material. The good news is that soft diaphrams have been known ot fix them selves over time, or can be rinsed gently in gasoline. This would explain the hiccuping on the highway, the occational bogging down when turning. It would also explain why your engine dies when you turn the throttle. If you can rev the engine by slowly opening the throttle, it would be another indicator that this is the case. Note that if you cannot rev the engine this way, it does not mean your diaphrams are fine. It would have little to no effect on idling, unless your pilot jets are not working properly, in which case it will play games with you.
The second problem, which may be independent or the result of the soft diaphrams, is that you seem to have lost some of your vacuum pressure. A leak in a seal, or a blockage of a port would explain why you can run on prime but not on the on position. This is assuming your petcock is working properly, and may contritube to why having the choke on helped. Does the choke make a difference when the petcock is in the prime position? Does the engine still die when the choke is turned off? Check your vacuum hose, especially the ends, for any possible leaks.
Possible third problem is blocked pilot jets are reducing the fuel flow at idle. It would explain point #2, and #3. However it would also mean your bike would run a little bit lean most of the time, which is contrary to the hiccupping and bogging.
You may also just be running really rich. What do the tips of your spark plugs look like? Is there is a difference in power, throttle response/bogging when the engine is cold and when it is warmed up?
Running on prime, by the way, would mean that your main jets at least are fine. (by running you mean it starts and idles, or can you actually ride as per usual, getting normal power and throttle response?) a botched petcock would explain a lot as well. You can test it by disconnecting the fuel line to the engine, and then using your mouth or a siringe to apply a light vacuum pressure through the vacuum line. If the gasoline comes pouring out, your petcock it just fine.
It's an interesting problem you have. Give as much detail as you can, may be you do not need to rebuild your carbs. PM me or post here if you'd like more info from me.
The interesting points so far are:
1: Carbs have been cleaned by running carb cleaner/other solvents. - I believe you have CV or vacume type carbs
2: It runs/ran better with the choke on, and dies when the choke is off
3: It ran better with the idle screw turned clockwise -> which i believe means with the butterfly valves are more open
4: The engine hiccups on the highway, and bogs down in a turn - Left and right turns? or only one side?
5: The engine starts with the petcock in the prime position, but not in the on position. - Had you reset the idle screw back to the original position, or was it still turned clockwise?
Its sounds like you have at least two, possibly three problems
The first is that I suspect the vacuum diaphrams in the top of each carb, which lift the vertical slides and let in more fuel, have either become soft, or one or more has a small leak. This is likely the result of a little too much carb cleaner being sprayed through the air intake, which softens the material. The good news is that soft diaphrams have been known ot fix them selves over time, or can be rinsed gently in gasoline. This would explain the hiccuping on the highway, the occational bogging down when turning. It would also explain why your engine dies when you turn the throttle. If you can rev the engine by slowly opening the throttle, it would be another indicator that this is the case. Note that if you cannot rev the engine this way, it does not mean your diaphrams are fine. It would have little to no effect on idling, unless your pilot jets are not working properly, in which case it will play games with you.
The second problem, which may be independent or the result of the soft diaphrams, is that you seem to have lost some of your vacuum pressure. A leak in a seal, or a blockage of a port would explain why you can run on prime but not on the on position. This is assuming your petcock is working properly, and may contritube to why having the choke on helped. Does the choke make a difference when the petcock is in the prime position? Does the engine still die when the choke is turned off? Check your vacuum hose, especially the ends, for any possible leaks.
Possible third problem is blocked pilot jets are reducing the fuel flow at idle. It would explain point #2, and #3. However it would also mean your bike would run a little bit lean most of the time, which is contrary to the hiccupping and bogging.
You may also just be running really rich. What do the tips of your spark plugs look like? Is there is a difference in power, throttle response/bogging when the engine is cold and when it is warmed up?
Running on prime, by the way, would mean that your main jets at least are fine. (by running you mean it starts and idles, or can you actually ride as per usual, getting normal power and throttle response?) a botched petcock would explain a lot as well. You can test it by disconnecting the fuel line to the engine, and then using your mouth or a siringe to apply a light vacuum pressure through the vacuum line. If the gasoline comes pouring out, your petcock it just fine.
It's an interesting problem you have. Give as much detail as you can, may be you do not need to rebuild your carbs. PM me or post here if you'd like more info from me.
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