GK76A Vacuum Port for Carb Sync?

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pOint_01
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GK76A Vacuum Port for Carb Sync?

Post by pOint_01 » Tue May 13, 2014 1:05 pm

Hi guys,

im looking for the Vacuum ports to screw in the brass connectors from the Carburettor Syncronizer pictured below:-

Image

Ive been told they are on the engine below the cylinders where the carb boots would fit on but i cant seem to find anything...

i was starting to question whether this carb sync kit would work with this bike but this youtube video shows it working but unfortunately doesnt show where its connect on the bike



Can anyone help me?

Thanx in advance!

panda
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Re: GK76A Vacuum Port for Carb Sync?

Post by panda » Tue May 13, 2014 5:16 pm

You dont need the brass screw in adaptors just take off the rubber covers on the carb tops [black plastic top part of carbs]
and push the pipes on that go to your gauges .hope this helps

panda
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Re: GK76A Vacuum Port for Carb Sync?

Post by panda » Tue May 13, 2014 5:41 pm

Forgot to say one has a pipe running to the fuel tap to operate the vacuum on off

pOint_01
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Re: GK76A Vacuum Port for Carb Sync?

Post by pOint_01 » Wed May 14, 2014 9:35 am

thanx panda!

could you confirm that these are the ports.

Probably slightly different to your bike as mine doesn't have a pipe running to the fuel tap...although it seems to have a broken port which has been patched up by silicon...

Image

Image

panda
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Re: GK76A Vacuum Port for Carb Sync?

Post by panda » Wed May 14, 2014 5:51 pm

Yep thats the ones .might be worth looking at your fuel tap probably has to be on prime to get fuel flow without a vacuum feed to make the tap open on the on position or reserve.

pOint_01
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Re: GK76A Vacuum Port for Carb Sync?

Post by pOint_01 » Thu May 15, 2014 10:26 am

thanx again panda! I will look at the fuel tap and might post another photo for help!

SevenThreeSeven
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Re: GK76A Vacuum Port for Carb Sync?

Post by SevenThreeSeven » Thu May 15, 2014 5:07 pm

That carb-sync video seemed strange to me. It seems wrong that the guy who is doing the sync has already connected the manometer array to the individual carb vacuum ports but he's still messing with the calibration valves on the lines.

I'm not an expert on these things but I thought that the calibration valve setup of the manometer array was supposed to be done on just one single cylinder's vacuum port while the engine idles at a known rpm. Each input line is connected in turn to that single cylinder at the same rpm and the calibration valve is adjusted so that each manometer registers the same. That way when you connect the manometer array to the individual cylinders you know they are all "referenced" at the same baseline.

willandrip
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Re: GK76A Vacuum Port for Carb Sync?

Post by willandrip » Fri May 16, 2014 9:17 am

SevenThreeSeven wrote:That carb-sync video seemed strange to me. It seems wrong that the guy who is doing the sync has already connected the manometer array to the individual carb vacuum ports but he's still messing with the calibration valves on the lines.

I'm not an expert on these things but I thought that the calibration valve setup of the manometer array was supposed to be done on just one single cylinder's vacuum port while the engine idles at a known rpm. Each input line is connected in turn to that single cylinder at the same rpm and the calibration valve is adjusted so that each manometer registers the same. That way when you connect the manometer array to the individual cylinders you know they are all "referenced" at the same baseline.

You are correct, but in the vid. it is the damping he is faffing with not the calibration.
A red box doth not a Snap On make.

pOint_01
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Re: GK76A Vacuum Port for Carb Sync?

Post by pOint_01 » Mon May 19, 2014 2:29 am

does anyone have the part number for the 2 fuel hoses?

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