I'm sure this has been answered many times before, but can I ask couple of questions. Please answer as if you are explaining to a child, or an idiot, or me!
1. When you sync the carbs, what exactly are actually you doing?
2. Now I actually have the engine running, I notice that some of the exhausts are a lot hotter than the others. Will syncing the carbs sort that, or is there something else I should be doing before or after?
As usual, many thanks for any advice you can give me.
Just noticed I have put this in the wrong section perhaps a moderator can correct this please. Many thanks.
Previous Rides,
1980 CB250N Good to learn on
1981 CX500 good mid range tourer, went to Austria on it!
1983 GL1100C Pride and joy, sold when I bought my 1st house, big mistake
1985 GL650 Silverwing another mistake, horrible bike
1986 CBX550 Good commuter
1989 Suzuki GS750 (1976) cheap and cheerful until a dog ran out in front of me on Xmas Eve, 1991
Current bikes
2010 CB1300 back on a bike after 19 years, two divorces, children grown up etc
1980 GL1100 NOW ON THE ROAD, still use CB1300.
you are adjusting them so the butterflies open at exactly the same time, thus insuring the same amount of power is coming from each cylinder at the same time.
I found the end of the internet
---- Bradshaw Bikes custom polishing for your wing. Visit us on facebook!
1978 Learning Experience
1980 County Road Hauler "Brain Damage"
1978 Cafe Custom Gl1000 "Vyper"
1977 Bulldog Inspired "Vaincre"
1981 Street Fighter GL1100 "No Quarter"
1983 Supercharged Street Drag "Anubis" (in worx)
1983 gl1100 mint restoration "Kristen"
1985 Aspencade..pondering.
Uneven temperatures can be caused by many things, including synch. First you need to synch the carbs, then check to see if the heat issue has equaled out. If not, them you need to adjust the mixture in each carb. Hot usually indicates a lean condition.
I found the end of the internet
---- Bradshaw Bikes custom polishing for your wing. Visit us on facebook!
1978 Learning Experience
1980 County Road Hauler "Brain Damage"
1978 Cafe Custom Gl1000 "Vyper"
1977 Bulldog Inspired "Vaincre"
1981 Street Fighter GL1100 "No Quarter"
1983 Supercharged Street Drag "Anubis" (in worx)
1983 gl1100 mint restoration "Kristen"
1985 Aspencade..pondering.
Thanks Sunnbobb for the simple answers and moving this to the correct section.
Previous Rides,
1980 CB250N Good to learn on
1981 CX500 good mid range tourer, went to Austria on it!
1983 GL1100C Pride and joy, sold when I bought my 1st house, big mistake
1985 GL650 Silverwing another mistake, horrible bike
1986 CBX550 Good commuter
1989 Suzuki GS750 (1976) cheap and cheerful until a dog ran out in front of me on Xmas Eve, 1991
Current bikes
2010 CB1300 back on a bike after 19 years, two divorces, children grown up etc
1980 GL1100 NOW ON THE ROAD, still use CB1300.
The sync process can also uncover a problem. If one or more of the cylinders won't come up to the others, it could be a clogged or partially clogged slow (idle jet). Could also be a plugged or partially plugged idle mixture circuit. That is usually found by performing the "idle drop" mixture setting procedure.
Don't be discouraged. It takes years and hundreds of carbs to gain a high level of proficiency working with carbs. As you may have realized. There can be more that one thing, and possible more, that will cause the exact same symptom.
Take for example and colder pipe than the others as the symptom. Possible problems are:
Carb sync.
Idle jet plugged or partially plugged.
Mixture set incorrectly.
Mixture circuit plugged or partially plugged.
Float level.
Clogged or partially clogged float valve screen.
Bad spark plug
Bad spark plug boot
Bad spark plug wire
Bad coil.
Valve lash out of spec.
Ignition timing.
I'm sure you've heard the expression before and I'll repeat it here.. "Everything affects everything".
sunnbobb wrote:you are adjusting them so the butterflies open at exactly the same time, thus insuring the same amount of power is coming from each cylinder at the same time.
I am not claiming to be an expert, but my understanding is that you are adjusting for even vacuum air/fuel flow and actually adjusting the butterfly's to whatever makes the vacuum the same. This could mean the butterfly's are not opening at the same rate. This is to adjust for anomalies/dead spots in the carb bodies and intake ports. The reason people port their intakes is to smooth/remove those anomalies in the fuel/air mixture flow.
It can also make up for a cylinder which has lower compression. If you have three cyl's at 150 and one at 140, they will pull unevenly despite a perfect bench sync.
Whatever I suggest here should be given ample time for a moderator to delicately correct. I apologize in advance.
77 WING, 1200 engine with 77 heads, cams, gl1100 foot pegs, Magna V65 front end, 764A carbs, [-gone Suzuki M109 monoshock--, replaced with gl1100 shocks] gl 1200 swing arm, gl1500 final drive, wheel and rear brakes Valkyrie seat, Meanstreak tank, Sportster pipes, Power Arc ignition off crank.
77 Wing. black
83 Wing, in pieces
"Continuing education is important even if the subject matter is fairly useless (as in this case)."---Greg Foresi
perhaps a moderator can correct this please. Many thanks.
