Left Bank carbs won’t sync

Information and questions on GL1100 Goldwings (1980-1983)
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Joined: Fri Nov 13, 2015 10:46 am
Location: St. Louis, MO
Motorcycle: 1982 GL1100

Left Bank carbs won’t sync

Post by DocDan »

I have an ‘82 gl1100 and I cannot get the left bank of carbs to sync to the right. Carbs 1&3 sync to 28cm(11in)Hg, carbs 2&4 sync to 18cm(7in)Hg at 950rpm. When I attempt to adjust carb 4 to carb 3, the rpms rise, so I adjust the throttle down. I kept doing this until the throttle adjustment screw fell out. The difference in vacuum pressures (10cm/4in) of the left and right will not narrow. I can widen them, which drops the rpms, by turning the #4 adjuster clockwise, but turning it counter-clockwise only causes the rpms to go up. Any advice would be greatly appreciated.

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Re: Left Bank carbs won’t sync

Post by DaveO430 »

They are probably just way out. What you need to do is a mechanical synch (bench synch) by removing the intake elbows and use a thin feeler gauge under the throttle plates to get them close. Then do the vacuum synch.
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2003 GL1800 - Illusion Blue
1996 GL1500 Aspencade - Pearl Blue
1992 GL1500 Aspencade -Candy Red
1980 GL1100 - Custom Cobalt Blue
1985 GL1200 Aspencade Brown
1983 CX500 Custom Red
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Re: Left Bank carbs won’t sync

Post by Wingsconsin »

I remember this problem on my old 1100 as well when I first got it.
The way I got around it was to synch them at higher RPMS -
Then to back the RPMs down and re-synch -- then repeat and repeat until I got it right.
The idle adjustment screw got a lot of work that day ...
But eventually I got it nearly perfect- and the bike ran great !
Better power - better fuel economy - easier starting -
Worth the effort - I didn't worry about the numbers on the synch gauge - jut that each cylinder was working equally -
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Your results may vary. Universal disclaimers apply.

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