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What symptoms would my bike have if my carbs were out of synch? Gonna synch them anyway but was just curious what other peoples experiences were....
 

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From what I've noticed, hard starts (rarely do I need choke unless it's cooler weather) and "oscillating" idle/throttle while riding. At least, those are the things I've noticed happen and when I do a carb-sync, they're not there or not nearly as apparent...
Could just be in my head though.
I'd like to hear some of the more-experienced members opinions here.
 

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id like to hear some more aswell
i have a sever back fire from the exhaust at mid range also the "oscillating" rpm at nutral thottle
i suspect the sync mabey just because ive never done it before though
 

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Intermittinet Popping while idiling, from the exh.
 

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I notice the oscillation, or climbing rpm at idle as well, and a little hesitation in acceleration. I'll post pics of my balancing tool. Wooden board 4.5', 10' clear tubing, and some atf. Works like a charm.
 

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It'll idle roughly, and sound uneven. One cylinder will be louder than the other and a good ear can hear it. You can watch the slides with the airbox off as you rev it to watch them lift at the same time, or not.

This brings up a good question about synching CV carbs: Is it better to have the slides working together or a gauge reading perfectly? Actually it should be both, but I've worked on bikes that could be dialed in with gauges yet the slides weren't working together. In that case it idled more smoothly set to the gauges but ran rougher and responded less crisply. I ended up eyeballing the slides and setting them to both raise at the same time and liked the way it ran.

Before you worry a bunch about carb synch, please check the valve clearances and make sure they are not only in spec but as close to the same for both cylinders. My 1K had all the valves technically 'in spec' but some were right on the tight limit so I adjusted them all to the loose spec. Engine picked up 300 rpm at idle and the previously perfectly (electronic gauge-TwinMax) synch job was WAY off. The valve clearances really dictate how much vacuum each cylinder makes at idle, so getting them equal helps you get the carbs to be equal.
 

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i always aligned my carbs' butterfly valves to start open with the same starting gap (from full shut, one has a tiny gap and i match them to each other). i haven't invested in a carb synch tool yet, but my method has worked wonderfully with no hesitation or oscillation, so i'm not worried about it. i'm glad to hear that Rob has had similar experience with it. oh, an i also set my valve clearances to top of the allowable spec range as they will only get tighter. this is my track bike i'm referring to, which means red-line will tighten clearances quicker than regular street bike anyway.
 

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its a little screw that has two springs in close proximity. idk what these are called. they basically adjust the effective length of the arm that connects the fwd and rear carbs bodies.

this screw:


on left side of carbs.
 

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Out of sync carbs might make the bike vibrate more.
or might not be hardly noticable

my carbs were synced every 7500 miles as recommended in the maintenance schedule

didn't even seem like it needed any kind ot tunup .......... until I got it back after service, like a brand new bike and I couldn't even tell it was not running up to snuff when I dropped it off
 

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^ good wisdom right there! Thanks RandyO
 

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or might not be hardly noticable

my carbs were synced every 7500 miles as recommended in the maintenance schedule

didn't even seem like it needed any kind ot tunup .......... until I got it back after service, like a brand new bike and I couldn't even tell it was not running up to snuff when I dropped it off
Is a sync the only thing they did? I thought my bike felt a lot smoother after a sync and nothing else. But this is only one of a few possibly symptoms.
 

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Is a sync the only thing they did? I thought my bike felt a lot smoother after a sync and nothing else. But this is only one of a few possibly symptoms.
no, I have dealer do complete recommended service, that includes new plugs as well and all the routine regular 3500-4000 miles service stuff as well, its more than just an oil change, most noticable service items are cleaning & lubing shifter linkage, cable ends, etc.
 
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