Post carb rebuild headache

Trkdrvr1376

CB750 Enthusiast
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New Hampshire
Good morning,
Last weekend after rebuilding carbs(80 750c) started bike using auxiliary fuel tank with filter. The bike started ran and adjusted idle and it idled on its own. Twist the throttle and it was slow to respond but did rev up. The air box/filter not connected nor was the breather tubes.
Ran bike on and off a couple times for a total of 15 minutes. Yesterday
I installed air box boots, breather and new air filter. Wanted it all connected before doing any adjustments. Now I can barely get the bike started, won't idle whatsoever and will not rev up. Pulled plugs and they were all dry. Have not touched the pilot screws at all. Question is
Do I reset them at 1 and1/2 turns out ? Any insight would be appreciated. Hope you all have a nice day
Paul
 
Good morning,
Last weekend after rebuilding carbs(80 750c) started bike using auxiliary fuel tank with filter. The bike started ran and adjusted idle and it idled on its own. Twist the throttle and it was slow to respond but did rev up. The air box/filter not connected nor was the breather tubes.
Ran bike on and off a couple times for a total of 15 minutes. Yesterday
I installed air box boots, breather and new air filter. Wanted it all connected before doing any adjustments. Now I can barely get the bike started, won't idle whatsoever and will not rev up. Pulled plugs and they were all dry. Have not touched the pilot screws at all. Question is
Do I reset them at 1 and1/2 turns out ? Any insight would be appreciated. Hope you all have a nice day
Paul
Set at 2 turns out
 
"Did not touch pilot screws at all". So you have no idea how they are set. Set to 1 1/2 to 2 turns out after lightly seating.

Seems if you rebuilt / cleaned the carbs pilot screw touching in mandatory.
 
Good morning,
Last weekend after rebuilding carbs(80 750c) started bike using auxiliary fuel tank with filter. The bike started ran and adjusted idle and it idled on its own. Twist the throttle and it was slow to respond but did rev up. The air box/filter not connected nor was the breather tubes.
Ran bike on and off a couple times for a total of 15 minutes. Yesterday
I installed air box boots, breather and new air filter. Wanted it all connected before doing any adjustments. Now I can barely get the bike started, won't idle whatsoever and will not rev up. Pulled plugs and they were all dry. Have not touched the pilot screws at all. Question is
Do I reset them at 1 and1/2 turns out ? Any insight would be appreciated. Hope you all have a nice day
Paul
I have a Carb Rebuilding manual from MacGregor Carb Cleaning Services. It suggests 3 turns.
Also, I could be wrong but I believe the amount of turns only affects idle air mixture. So the amount of turns out does not affect when the throttle is opened wider.
Did you sync the carbs?
 
"Did not touch pilot screws at all". So you have no idea how they are set. Set to 1 1/2 to 2 turns out after lightly seating.

Seems if you rebuilt / cleaned the carbs pilot screw touching in mandatory.
Sorry I should have clarified it that I didn’t not touch pilot screws after it was running.
Just got done putting carbs back on bike.
The pilot screw on carb #2 was loose as a goose. I could grab it in my fingers and it wiggled. It seems the springs that came with rebuild kit were a little shorter than originals.
Thankfully I saved the originals and installed all four also set them to 2 and 1/2 turns.
Bike started and very responsive to throttle.
Idles high due to air box not being connected.
Tomorrow I will install boots and new air filter.
Also ordered a carb sync tool to fine tune.
Thanks for info
Paul
 
I have a Carb Rebuilding manual from MacGregor Carb Cleaning Services. It suggests 3 turns.
Also, I could be wrong but I believe the amount of turns only affects idle air mixture. So the amount of turns out does not affect when the throttle is opened wider.
Did you sync the carbs?
Have not synced them but that is on the short list of things to do. This bike is a rescue that has not been registered since 2011 so still trying to figure out if it’s worth time and effort.
So far I am all in on getting this one back on the road
Thanks
 
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