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Keihin Carb Questions...help please!

Aahridey

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Hi, I bought a 1982 DOHC 750 F2 about a year ago. I bought it as a non runner but a new battery and fresh fuel had it up and running, if a little rough.

I took the carbs of and gave them a bit if a clean and reinstalled. However, the carbs wouldn't fill with fuel. I've checked the fuel tap and the fuel flows out freely but won't run into the carbs. I suspect that it is a vacuum problem however the fuel tap only has one outlet and no vacuum spout.
I have been able to get some fuel into the carbs very slowly by tipping fuel into the inlet pipe and turning over the engine,.....this does slowly allow fuel into the carbs, but although I get the odd splutter and backfire, it won't start.

There seems to be some sort of vacuum control on top of the carb, with a pipe that doesn't go anywhere. Should this be connected to something? There's also a pipe going nowhere from a stub between carbs 2 and 3.

Should one be connected to the other? I've seen a diagram on the net which suggests this....

Should that vacuum pipe (?) on top of the carb be connected to something else? Should it connect to a vacuum outlet on a double spout fuel tap?

Is that pipe between the carbs just a vent pipe

Should either of them be capped?

.....oh I should add that the air box is missing and I have the dreaded pods fitted......

Any help would be much appreciated!!

Thanks, Mark
 
'There's also a pipe going nowhere from a stub between carbs 2 and 3.'

That vents the carbs. The small line coming off the vacuum valve is a vent too, leave them open. There needs to be a line coming off the front of carb #2 to go to valve to activate it.

You can remove the entire 'automatic fuel valve' to use the petcock only and what most do when the valve gets hard as rock inside to not open correctly.
 
Also, what connects to the small black "T" between 2/3?

This small "T" has a small piece of hose on either side of it as well.
 
The same one I just referred to with the quoted sentence. The 'T' simply gets a longer piece of carryoff tubing to go to the same place as all the bowl bottom drains, down behind the right rear of the motor to drain on the ground, some bikes even have a collecting ring that bolts to the engine at that point.
 
10-4! Got it, thanks. Ill probably get some hoses and vacuum t fittings to collect all 4 carb drains.
 
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