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Carb synchronization question

nightengale

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I've rebuilt the carb bank on my '82 CB750 Custom, per these instructions: http://www.cb750c.com/publicdocs/SeanG/Honda_Carb_Manual_revG.pdf

Bike is still hard starting at the moment. Once it's warmed up, starts just fine, but I have to use a bit of starting fluid if it's cold (fresh battery, full charge, decent spark, gaps good). I don't know the ohms being generated by the coils or ignitors.

I do not own a carb synchronization tool, but thinking about obtaining one (live in the sticks, shop prices to do this seem way too high). But honestly can't figure out "where" to make the connections if I did have the tool. This is my main question - where exactly DO you connect one of these tools? Or is the tool something other then what I think?

Way back, I had one of these carb synch gauges that had four mercury level gauges, each one connected to each carb via a vacuum line. But I don't actually know where those ports are on the stock Kehin carbs I've got.

Carb #2 has a vacuum port, which I've plugged off and removed the spawn of Satan vacuum assist for the fuel line (this is also where I can cheat and give a little squirt of ether to start the cold engine, seems to work as well as trying this in the air-cleaner box and is easier to do).

But where do they connect on carbs #1,#3,#4? I know you set carb #2 and then adjust visually (and with a little wire) the other carbs to match #2 (that's the bench synching, along with the idle mixture screws being adjusted the same). But I don't know where I'd connect the carb synchronization tool if I had access to one. What am I missing here?

The bike has fresh fuel, new inline filter, etc., and the carbs had the full kit repair (needles, jets, o-rings, cleaning, etc). I've taken the carbs off 3 times to try to find out if something is wrong, but haven't actually found anything to solve the cold-start issue (and its not cold here - garage is 70+). They've only been "bench synched" per the instruction manual linked above.

Minor adjustment to the idle mixture screws haven't solved the cold-start problem by the way.
 
The pilot jets are commonly plugged and super hard to get 100% clean and you cannot see the problem.

The syncing vacuum takeoff points are in the head, the small phillips screws you see just in front of the front carb manifolds.
 
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