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Author Topic: Does carb sync affect timing?  (Read 2625 times)

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Offline gregripko

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Does carb sync affect timing?
« on: March 16, 2013, 05:47:27 PM »
....well....does it?
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Offline toytuff

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Re: Does carb sync affect timing?
« Reply #1 on: March 16, 2013, 05:59:54 PM »
 :o

tt
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Offline gregripko

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Re: Does carb sync affect timing?
« Reply #2 on: March 16, 2013, 06:36:55 PM »
Are there any circumstances that it can change timing.... Is probably a more accurate question
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Offline Dimitri13

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Re: Does carb sync affect timing?
« Reply #3 on: March 16, 2013, 06:56:44 PM »
No. It will change the idle though.
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Offline toytuff

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Re: Does carb sync affect timing?
« Reply #4 on: March 16, 2013, 07:08:11 PM »
Quote from: gregripko on March 16, 2013, 06:36:55 PM
Are there any circumstances that it can change timing.... Is probably a more accurate question

Well it does sound better.  ;)

I would say no. Carburetor sync is for idle. Once you open the throttle the cylinders take what they can. I might be wrong and no expert on the subject. Timing is when the plug fires. (as you probably already know  :) )

tt
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Offline crazypj

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Re: Does carb sync affect timing?
« Reply #5 on: March 16, 2013, 07:15:54 PM »
Only if idle is too high(around 1700 rpm)
The advance unit is just starting to operate around that rpm so if you set timing at high idle with carbs way out of sync then did carb sync and lowered idle speed,the timing could be wrong
Otherwise, NO, carb sync has nothing to do with timing
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Does carb sync affect timing?
« Reply #6 on: March 16, 2013, 07:18:36 PM »
Timing (cam, valves and crank) is set.

Ignition timing is a different story. If jacked up carbs cause bad running then perhaps that advancer won't act normally and could be erratic? 
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Offline gregripko

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Re: Does carb sync affect timing?
« Reply #7 on: March 16, 2013, 08:41:18 PM »
I synced carbs and they are super level.... But! The previous tool I used sucked up a little gear oil....probably like a half cup in all... Would this affect performance? Just feel like it was accelerating a little erratic today....
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Offline brewsky

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Re: Does carb sync affect timing?
« Reply #8 on: March 17, 2013, 04:12:13 AM »
Quote from: gregripko on March 16, 2013, 08:41:18 PM
sucked up a little gear oil....probably like a half cup in all...

1/2 CUP????

Lucky the engine isn't locked up!

Change plugs and go from there.
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Offline gregripko

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Re: Does carb sync affect timing?
« Reply #9 on: March 17, 2013, 08:46:01 AM »
Gear oil is suggested over water or other potentially harmful liquids in sync tools.... Would the oil be burned up or is it now mixed with the other oil? Ok it's probably not a half cup... Probably 1/4 cup but still....
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Offline rb550four

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Re: Does carb sync affect timing?
« Reply #10 on: March 17, 2013, 09:18:25 AM »
Okay,I'm trying to follow along, it isn't early enough to have had too much brandy yet.....
 but, why the hell would your sync tool (vacuum  gauges ) have any oil or water in them? What have you plugged them into to introduce these liquids to these tools?
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Offline BobbyR

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Re: Does carb sync affect timing?
« Reply #11 on: March 17, 2013, 09:33:27 AM »
Since you sucked up the oil and the motor did not lock up the only thing you may have done really foul the plugs. That is heavy Oil and quite a bit also. Bet she smoked like hell. ;D
You may want to pull the plugs and burn them clean with a propane torch and brush off the crap. If they have been in there a while you may want to change them.
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Offline Vinhead1957

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Re: Does carb sync affect timing?
« Reply #12 on: March 17, 2013, 10:09:15 AM »
Water in the right delivery can be beneficial! Dragsters mist water to the intakes to clean carbon out to squeeze out every bit of horsepower.  Old cars used to actually have a canister for the same purpose.  Steam clean internally. The downside is that water in the liquid form does not compress. If the combustion chamber gets too full the pressure has to go somewhere.  Head gasket becomes the victim usually.
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Offline crazypj

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Re: Does carb sync affect timing?
« Reply #13 on: March 17, 2013, 11:29:01 AM »
Quote from: rb550four on March 17, 2013, 09:18:25 AM
Okay,I'm trying to follow along, it isn't early enough to have had too much brandy yet.....
 but, why the hell would your sync tool (vacuum  gauges ) have any oil or water in them? What have you plugged them into to introduce these liquids to these tools?

DIY Manometer.
Probably need longer lines and restrictors
the gear oil can't mix with engine oil, one is above piston the other below
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Offline BobbyR

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Re: Does carb sync affect timing?
« Reply #14 on: March 17, 2013, 12:16:59 PM »
Get some dial guages. Cheap, effective, and one set will last you a lifetime.
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Offline HondanutRider

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Re: Does carb sync affect timing?
« Reply #15 on: March 17, 2013, 12:36:31 PM »
Back to your original question: No, synchronization of the carbs cannot affect or change the timing. 

However, timing could affect and change the synchronization.  This would be because each pair of cylinders has a different set of points (1&4 and another for 2&3).  If they are set to fire at different degrees than each other, then a synchronization of the carbs would likely be disturbed.  If you synched them with one setting and then had the timing of one of the points altered, then the original synch would be off.  That is why you get the timing correct BEFORE doing a carb synch, and also first get the tappets set properly as that can also alter a synchronization of the carbs.
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Offline BobbyR

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Re: Does carb sync affect timing?
« Reply #16 on: March 17, 2013, 02:13:45 PM »
Actually the sequence is:

Adjust the valves
Set the Points
Adjust the Timing

Once you have everything within spec, you then synch the carbs.
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Offline lucky

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Re: Does carb sync affect timing?
« Reply #17 on: March 18, 2013, 03:39:51 PM »
Quote from: BobbyR on March 17, 2013, 12:16:59 PM
Get some dial guages. Cheap, effective, and one set will last you a lifetime.

I agree.
Those are the easiest to use. No damn bubbles or fluid getting sucked out.
No expensive fluid to order and replace. Dumb.

Get the dial gauges and be done.
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Offline gregripko

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Re: Does carb sync affect timing?
« Reply #18 on: March 18, 2013, 03:55:13 PM »
I made an epic carb sync tool the second go and it doesn't suck up any fluids....


.....two snapple bottles.....tub/sink plugs on top....fish tank lines ......you know...anyways...i couldn't believe how well it worked....it's like magic watching the levels adjust....
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Offline Duke McDukiedook

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Re: Does carb sync affect timing?
« Reply #19 on: March 19, 2013, 02:41:41 PM »
Sounds more like gear for an epic water bong than carb sync tools.
Does this setup measure all four carbs all at one time?
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Offline Duanob

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Re: Does carb sync affect timing?
« Reply #20 on: March 19, 2013, 04:12:40 PM »
Quote from: gregripko on March 18, 2013, 03:55:13 PM
I made an epic carb sync tool the second go and it doesn't suck up any fluids....


.....two snapple bottles.....tub/sink plugs on top....fish tank lines ......you know...anyways...i couldn't believe how well it worked....it's like magic watching the levels adjust....

Pics or it didn't happen!  8) vids are even better.
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Offline Gregorymoto

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Re: Does carb sync affect timing?
« Reply #21 on: March 19, 2013, 04:45:18 PM »
I would suggest reading the manual and give it some thought. If that does not help you sort out that question, you should definitely take your bike to a shop. lol
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