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CB750 F2

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blackeagles:
following on from my earlier post about drive chain noise and syncing the carb to help....i have been having a little trouble setting them up and i just noticed, looking at an illustration of the pd42 carb, that the 3 pipes that connect the acc. pump to each carb seem to have a restrictor in each (is it part number 16026-393-004 or maybe that is what joins the carbs fuel supply together).  no surprise when i took the old pipes off they didn't have such a restrictor so i have not used one....is that likely to cause an issue with setting the sync or the slow running????

bearing in mind they cannot be obtained (as far as i know)

K2-K6:
I think it has the potential to bleed through and affect mixture when not intended,  whether it's doing that I can't immediately think of a competent and easy check.

Ordinarily the system is supposed to work as requires pressure to force the fuel out only when pump breaches the restriction,  so you could see a pathway if not there as it should not contribute under any non pumped condition.  That's true of any accelerator pump design as you'd not want vacuum pulling fuel through that's essentially unplanned. 

We'll need to try to come up with a logical method to isolate or prove the affect and affect a cure if that's the case.

blackeagles:
i have had another close look at a number of diagrams online and the 3 acc. pump rubber hoses between the carbs do not seem to show a restrictor to fit into them.

i got the idea they may need such a restrictor(s) as i came across a post on this site that mentioned there were "3 brass restrictors per pipe" and i am guessing that if they actually exist they will be unobtainable or, of course, i may have misread the post (not that i can find it again anyway).

royhall:
They were just open brass pipes in mine not restrictors.

K2-K6:
Have you a local mot station that would be willing to give you a set of exhaust emission readings to see where you are?

Thinking along the lines of setup as best you think you can obtain,  then get a test with it warmed up to confirm where it's sitting from analysis.

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