Topic: Cant get her to run without choke being on

[mgl01]

I know this isn't a unique topic but I seem to have a unique issue....I have read every post and tried most all suggested fixes - my bike only stays running with choke on.
It was a barn find of which I have changed oil, plugs and went as far as replacing coils, wires and points with the Pamco system. 
Bike starts first time every time - only if the choke is on! If I take the choke off - it dies.  Had carbs rebuilt by Mike Nixon and am running an external fuel canister to be sure I'm not dealing with bad fuel. Timing is difficult to get a read on because it idles very high - also cant lower the idle speed or it dies.
I currently have carbs air/fuel adjusted to about 2 turns out - 1 1/8 out as factory suggests vs 2 out really doesn't seem to matter.
What am I missing? any help would be greatly appreciated.

[b52bombardier1]

It's either a vacuum leak or the carbs are still dirty. My guess would be carbs.

If carbs sit for a long time, it often takes more than one cleaning to get them correctly and completely clean. Running new fuel through them acts as a solvent that the first or maybe even second cleaning did not remove.

Rick

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[7T1Burb]

1.  Spray carb boots with "carb cleaner" with the engine running (in your case with the engine running on the least amount of CHOKE).  If RPM increases as you spray then it's an indication of a vacuum leak and more than likely at the carb boots.  They get rock hard over time and fail to seal properly.  Tightening the boot clamps to the "max" on rock hard boots normally does little to no good.  I recently purchased a brand new set of carb boots from Vintage750 and they solved the problem I was experiencing (the very same problem you're currently facing).

2.  If the above does not solve the problem of being unable to obtain a good idle and you have determined there are no vacuum leaks whatsoever then I would suggest you consider rechecking the balance/synchronization of your carbs. (BTW...Mike Nickson builds great carbs but carbs have to be synched to YOUR engine's operating characteristics on your running engine.  Bench synching is OK, but to get a valid carburetor synch they have to be on your running engine)
-  pull carb top covers off 1, 3 and 4.
-  remove vacuum port screws from 1,3 and 4. NOTE:  Carb #2 is not adjustable and is the "base" carb so just slip off the solenoid and check valve hose and attach your vacuum line to the available #2 carb port. 
-  with the vacuum gauges attached to 1,2,3 & 4 and engine running (in your case with the least amount of CHOKE to keep  it running) , synch 1, 3 & 4 vacuum readings to carb #2 vacuum reading.  Synch is obtained my loosening the locknut of the carb you're synching and adjusting the reading on that carb gauge to carb # 2 reading with a small flat blade screwdriver.

NOTE: as you synch each carb and begin to come off CHOKE to get a good idle, you'll have to "fiddle" with the idle adjustment screw to get a decent idle.

I've got my air/fuel adjustments to 1 1/4.


Gook Luck and let us know how your progressing!

[mgl01]

Whats the correct order in your opinion to snych first or adjust air/fuel mixture

[dave the welder]

sync first

[flybox1]

Are you operating the choke correctly?
Use the choke (to close the butterfly valves) and start it.
As it warms, you should be able to lower the amount of choke needed.
As you move closer to taking the choke off, turn in the idle set screw to keep the bike from dying.