Poll

In your experience, what is your preferred "weapon of choice" for syncing carbs?

Set of four analog-type vacuum gauges
Mercury Manometer
Morgan Carbtune
Homemade syncing device built from plans
I'm an old timer and can do it by ear!
What's carb syncing???
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Author Topic: How do YOU prefer to synchronize carbs?  (Read 12163 times)

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Offline Jonesy

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How do YOU prefer to synchronize carbs?
« on: May 05, 2005, 07:13:11 AM »
Some of the recent question about carbs got me to wondering if there is "THE" proper way to balance carburetors? Some use dampeners to get steady readings, some say dampeners delay gauge response and throw off the tuning. Some say to balance them at 2,000-3,000 RPM to get the best balance in the power band, while others say to do it at idle... (You see where I'm going with this...)

The only thing everyone seems to agree on is that the engine should be fully warmed up and "gone through" tuning wise (valves, floats, timing, plugs, etc... up to snuff) before proceeding. So, anyone got any special techniques for doing it? Any tricks you've learned to make it easier? I seem to get mine sync'ed OK, but the engine still rattles in neutral, so I think I need to practice and learn more. The biggest thing I've discovered is to be patient!
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Offline Bob Wessner

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Re: How do YOU prefer to synchronize carbs?
« Reply #1 on: May 05, 2005, 07:25:30 AM »
My trick is to never start the process without setting the appropriate atmosphere. I hold this sign up in front of the headlight so the beast can see I mean business  ;D
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Offline MRieck

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Re: How do YOU prefer to synchronize carbs?
« Reply #2 on: May 05, 2005, 08:50:14 AM »
Make sure your battery is fully charged as extended idleing will drain it quickly. Put a floor fan in front of the engine if you require extra time to get it right. Set them at proper idle speed which really requires an electronic tach ( like on a dwell meter).
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Offline dpen

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Re: How do YOU prefer to synchronize carbs?
« Reply #3 on: May 05, 2005, 12:26:29 PM »
I purchased a set of four gauges from an Australian company-Z Power. Quite cheap & a lot easier & more accurate than the mercury columns I previously used.

Engine warm & in good tune (valve clearances, dwell etc). If you have adjustable air screws on the carbs set them to 1 1/2 turns out.
Remove the airfilter element.
Some people & manuals set specific limits but my K7 was running so rough it "hunted" between 1,000 & 1500 revs so I just started from there.
Take the flutter out of the gauges with the valves supplied & tune each carby as close as possible to the reading on no 2 cylinder (the one you can't adjust).
Engine running a lot more smoothly, take the idle down as far as possible & adjust carbies again.
I have the adjustable pilot screws on the carbies so I adjusted them with a remote tacho and presto--steady idle at 1,000 and no cam chain rattle.
Only trouble is I can now hear the clutch rattle.
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eldar

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Re: How do YOU prefer to synchronize carbs?
« Reply #4 on: May 05, 2005, 02:22:34 PM »
I like to just cut my cabels and yank the bank off while tipping over the bike on my foot at the same time. Then in a fit of pain induced rage, I throw them on the ground and watch them bounce at that point they are synced.

OH wait, that what I like to imagine doing, that right ;D
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Offline Jonesy

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Re: How do YOU prefer to synchronize carbs?
« Reply #5 on: September 05, 2005, 09:05:07 AM »
Could we stuff this one in the "POLLS" section?

Thanks. :)
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ElCheapo

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Re: How do YOU prefer to synchronize carbs?
« Reply #6 on: September 05, 2005, 08:43:49 PM »
Twirl chicken overhead, close one eye, let your tongue hang out for style, and curse until finished.

Really I use good old fashoined carb spray. Give her a tiny squirt of carb spray - she bogs, she is right. No bog better double check for spark. Idle climbs she is too lean.
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Offline MikeDeB

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Re: How do YOU prefer to synchronize carbs?
« Reply #7 on: September 06, 2005, 02:20:55 AM »
Morgan Carbtune for sure!  After all other settings are correct and the engine warmed up and idle set then I begin the synch.  Even after they're set you will still get a little rattle from the engine at idle with the bike in neutral and clutch out.  It's clutch rattle.  When the carbs are really out of synch it pronounces the clutch rattle and adds primary chain rattle to it.  Both of my running CB's have their carbs synched and I still get a little rattle out of them.
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Offline Gordon

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Re: How do YOU prefer to synchronize carbs?
« Reply #8 on: September 06, 2005, 07:49:22 AM »
Quote from: ElCheapo on September 05, 2005, 08:43:49 PM

Really I use good old fashoined carb spray. Give her a tiny squirt of carb spray - she bogs, she is right. No bog better double check for spark. Idle climbs she is too lean.


Carb synching is an entirely different procedure from idle mixture adjustment.  You should try it sometime.
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Offline Terry in Australia

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Re: How do YOU prefer to synchronize carbs?
« Reply #9 on: September 07, 2005, 04:28:37 AM »
I use a piece of wire to "bench synch" them. This is not the "be all and end all" of course, but it gives you a really good base line for further tuning.

Having said that, after bench synching, most times I don't bother with my Morgan Carbtune. It's a great device (pisses all over analogue gauges IMHO) but the bikes start and run smooth enough without further tuning, allowing me more time to plot the overthrow of the free world, and the kidnapping of Heffay's girlfriend! Cheers, "Triple S"  ;D
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eldar

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Re: How do YOU prefer to synchronize carbs?
« Reply #10 on: September 07, 2005, 05:21:20 PM »
I might help with that plot but I would need to see a pic first! ;D
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Offline DammitDan

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Re: How do YOU prefer to synchronize carbs?
« Reply #11 on: September 08, 2005, 10:19:25 PM »


Just look at that beautiful scooter.
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Williamsd

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Re: How do YOU prefer to synchronize carbs?
« Reply #12 on: September 09, 2005, 12:02:15 PM »
I borrowed a mercury synchronizer from a mechanic friend.
At about 2 feet tall, it was huge compared to what I envisioned when I looked at pictures of the Morgan Carbtune.
There were no regulators so there was a fair bit of action in the mercury levels.
It seemed to go well, much better idle, a little less chain noise and a lot less backfire on engine-braking.

Question....  the bike is a 1982 650 Nighthawk.  It has adjustable pilot screws.  As I was cleaning the carbs, following the Chilton manual which says to count the pilot screw turns, I found quite a difference between the cars.  #1 was 1/2 turn, #2 & #3 were 1 turn and #4 was 1-1/2.  What do you think of this?  I don't have the book with me so I can't look up their recommendation for pilot adjustment.

 
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Offline Cvillechopper

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Re: How do YOU prefer to synchronize carbs?
« Reply #13 on: September 10, 2005, 06:20:04 PM »
I think I passed out...  That "scooter" was too much for me damnitdan.  You should warn people.



Quote from: Williamsd on September 09, 2005, 12:02:15 PM
I borrowed a mercury synchronizer from a mechanic friend.
At about 2 feet tall, it was huge compared to what I envisioned when I looked at pictures of the Morgan Carbtune.
There were no regulators so there was a fair bit of action in the mercury levels.
It seemed to go well, much better idle, a little less chain noise and a lot less backfire on engine-braking.

Question....  the bike is a 1982 650 Nighthawk.  It has adjustable pilot screws.  As I was cleaning the carbs, following the Chilton manual which says to count the pilot screw turns, I found quite a difference between the cars.  #1 was 1/2 turn, #2 & #3 were 1 turn and #4 was 1-1/2.  What do you think of this?  I don't have the book with me so I can't look up their recommendation for pilot adjustment.

 

Were they far off when you synched them?  That seems like someone trying to get the carb mixture adjusted without getting them synched first.  I know this from my first attempt to adjust a 4 carb set-up.  Not pretty. 

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Offline Quail "Owner of the comfortable k8"

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Re: How do YOU prefer to synchronize carbs?
« Reply #14 on: October 06, 2005, 11:13:01 PM »
YOU YOUNG GUYS HAVE TO GIVE US OLD FARTS A WARNING.  YOU CAN'T JUST POST BIKE PHOTOS WITH CHICKS.  Some old guy is out there right now "air humping" because  you did not warn him. 
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Offline dusterdude

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Re: How do YOU prefer to synchronize carbs?
« Reply #15 on: October 07, 2005, 06:59:24 AM »
sorry guys,i dont see no stinkin scooter
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eldar

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Re: How do YOU prefer to synchronize carbs?
« Reply #16 on: October 07, 2005, 08:40:19 AM »
Yeah She's a nice looking blonde scooter allright! ;D
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jaannaktin

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Re: How do YOU prefer to synchronize carbs?
« Reply #17 on: October 07, 2005, 09:55:08 AM »
 ;)

I had to learn to use the mouse with my left hand to enjoy that scooter picture. How bout another!

 ;D
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Offline Quail "Owner of the comfortable k8"

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Re: How do YOU prefer to synchronize carbs?
« Reply #18 on: October 07, 2005, 10:57:34 AM »
I was on my work the other day and picked up a hitchhiker....I explaind there was only one place to sit.... and this is my favorite way to sync carbs.
« Last Edit: October 07, 2005, 10:59:49 AM by Quail "BIRDMAN OF THE k8" »
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These wonderful little birds are great flyers, delicious eating, excellent for training your hunting dog, and just fun to shoot,or stuff and keep around the house.  Bobwhites can be put with other types of Quail and have very large penis's.  Quail are very popular with the babes.

eldar

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Re: How do YOU prefer to synchronize carbs?
« Reply #19 on: October 10, 2005, 12:20:47 PM »
I wonder how that affects the control?? Them clothes do change aerodynamics!
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Offline DammitDan

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Re: How do YOU prefer to synchronize carbs?
« Reply #20 on: October 10, 2005, 02:36:40 PM »
Crazy kids...  Like rabbits...   ;D
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eldar

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Re: How do YOU prefer to synchronize carbs?
« Reply #21 on: October 11, 2005, 08:21:16 AM »
I still think the clothing on that scooter might cause problems!
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Offline Einyodeler

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Re: How do YOU prefer to synchronize carbs?
« Reply #22 on: October 11, 2005, 09:15:16 AM »
That`s just a dry run..........or is it dry hump ???

I made my own set with gauges,homemade brass inserts,aquarium air lines and check valves and it works great.
But just like Terry said you need to do a GOOD benchsynch first or you`ll be spending a LOT of time getting them dialed in for the final synch.
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Offline Terry in Australia

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Re: How do YOU prefer to synchronize carbs?
« Reply #23 on: October 11, 2005, 01:58:21 PM »
What was the question again? Dry humping blondes on scooters? I'm lost, I better go back to the beginning, ha ha! Cheers, Terry. ;D
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Offline DammitDan

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Re: How do YOU prefer to synchronize carbs?
« Reply #24 on: October 12, 2005, 09:16:02 AM »
Look how compressed those front shocks are... All's it would take is one pothole, and your girlfriend now looks like a leper!
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