Carb sync????

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Mar 23, 2014
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Had my bike in and they told me that my carbs are slightly out of sync how big of a problem is this as far as riding with them out of sync??? have just had a lot of work done including new timing belt and getting carbs synced are not in budget so am wondering if I will hurt my bike if I do some riding before they get synced...It is on a 1991 st 1100 with about 84000 miles...
 
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Ride it... the carbs needing sync will not hurt anything... it just will not perform 100%. It is not a big job to sync the carbs as long as nothing else is amiss. Look for and attend a tech event somewhere within riding distance. You can learn a lot about some of the maintenance and possibly save yourself a bunch of cash.:)
 
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Bedford,Texas
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#8753
Yep what Vinny said, I talked about doing my carbs right after getting my bike and a gentleman(nuhondaguy) came to my house and helped me do it, I was able to borrow the synch tool from Mellow, not real hard to do just can be a little intimidating untill you do it once,post where you are located and you may have help crawling out of the woodwork
 
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Had my bike in and they told me that my carbs are slightly out of sync how big of a problem is this as far as riding with them out of sync??? have just had a lot of work done including new timing belt and getting carbs synced are not in budget so am wondering if I will hurt my bike if I do some riding before they get synced...It is on a 1991 st 1100 with about 84000 miles...
I'm wondering how they knew the carbs were "slightly" out of sync, unless they put the tool on the bike? Could be something else going on in those carbs, if it is running rough enough for them to consider that. Are you feeling vibration in the bars when riding?

Here's another option for you and a chance to start digging into it yourself to learn and save some dollars. This comment will elicit jeers of ridicule from the carb stick fanatics here, but you can buy yourself a tool called a Flowmeter, for about $30.00 and do the carb sync yourself. It *may* not be as spot on a sync as the perfectionists prefer, but it does the job quite well and is easy to use.
 
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I synched carbs for about 20-25 years and honestly could never tell any difference between out of sync and perfectly synched. I haven't synched my ST in over 10 years, maybe longer. I still get the same gas mileage as always, idles the same as always, runs the same as always. If I could buy some replacement mercury for my current carb stix I'd consider synching them again, but since I can't I don't worry about it.
 
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Actually, early on, first indication of 'out of sync' is an ever-so-slight idle fluxuation at operating temperatures;). As for smoother running and mileage back up with an overall increase of 6mpg, new perfect sealing carbs boots when I had to replace coolant elbows/o-rings attribute to majority of noticed smoothness/mileage increase along with running again at a more constant operating temperature.
 
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ryterafan
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I actually am in IN... They did the timing belt and had it running for about 45min and told me that the carbs were slightly out of sync.... I am wondering if they aren't just trying to make some more $$$$ To do timing belt, tensioner,and pullies parts and labour came up to just over $650....
 
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I actually am in IN... They did the timing belt and had it running for about 45min and told me that the carbs were slightly out of sync.... I am wondering if they aren't just trying to make some more $$$$ To do timing belt, tensioner,and pullies parts and labour came up to just over $650....
That's not a bad price because there is a lot of labor involved in changing the timing belt.
 
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That's not a bad price because there is a lot of labor involved in changing the timing belt.
+1 on the cost......very reasonable. Hopefully, the work was quality too. They are likely correct 'carbs needing sync'ed, but isn't gonna cause any damage if not done. Just depends on how silky-smooth you want it to perform;).
 
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Las Vegas, , Nevada
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94' 1100 ABS
I have a synch tool, snorkel type, but I have never done this procedure. Any good links to how it's done, I have two st 1100's that need to be done. Or, is anyone interested in showing me in the Las Vegas area. I am now in the process or taking apart a gummed up carburator and cleaning fuel tanks. All I really need to know is which screw gets adjusted during the synch process. Thanks for all the good advice on this site...........Rod
 

Uncle Phil

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Using the Flowmeter is pretty simple. I find it easier to remove the air cleaner (top and bottom) so I can get to the adjustment screws. You'll need a really long Phillips screw driver. I first put the Flowmeter in the 'snorkel' of carb 4 (back left side). Then I adjust the idle via the knob at the gas cap to get it to a easy to read level. Then you move the Flowmeter to the other snorkels and adjust them to match the reading from carb 4. The adjustment screws are down between the carbs on the outside (a flashlight is handy). Be advised if you let the screwdriver 'rest' on the screws you will skew the readings. ;-)
 

John OoSTerhuis

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N.B. - Don't follow the Haynes manual's sync instructions! The other three carbs are all sync'd individually, in any order, to the base carb (#4), idle set to spec (and maybe reset if necessary during).
 
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ST1100Y

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... I am wondering if they aren't just trying to make some more $$$$...
The 4 carbs are connected by mechanical linkage, which does alter over use... therefore is re-syncing them (or at least check) quite a common, frequent task... having equal output on all 4 cylinders again also greatly reduces/eliminates engine vibration/buzz... improved mileage, better "ohmp", easier starting...
So suggesting carb sync is not an attempt to rip off... its a common, useful thing...

To do timing belt, tensioner,and pullies parts and labour came up to just over $650....
Awesome, amazing prices... I'm seriously considering emigration again...
 
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Apr 30, 2014
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Las Vegas, , Nevada
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Thanks, when I get back home this will be my project, along with finishing the carb dismantle and cleanout. Thanks all...(John, Phil, STY).....Rod
 
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