vtr 1000 carbs

I'm having this problem:
My bike will start up when it's cold , with the choke(enricher)
engaged. As it warms up it begins to stumble/miss until it dies. If I
open the throttle as it is warming up, the rpms will rise then the
motor stumbles and dies.I've pulled the carbs off and cleaned and used
compressed air to blow out the passages and jets. I didn't mess with
the idle screw/jets because they're sealed (CA model).Right after it
dies If I open the throttle butterflies and hold open the vacuum slides
I can see a dense fog og gas in the rear carb but nothing in the front.
How can I differentiate between the rear carb flooding or the front car
starving. Any thoughts would be appreciated
Barry

 

Carefully feel the exhaust pipes with your hand. If the front pipe is
cold, that cylinder is probably too lean to fire. Pull the spark plugs
and examine them for color and wetness. If the rear plug is wet, maybe
you have a fuel shutoff needle valve that's sticking...

For a thorough carb cleaning, you really do need to follow the EPA
anti-tamper plug removal procedure I've described many, many, many
times. Google up "kaybearjr +EPA" and follow the procedure...

You might just get away with running 2 or 3 ounces of Berryman's B-12
Chemtool Choke and Carburetor Cleaner through 3 or 4 tanks of gas until
the engine runs better. Don't run the engine hard with B-12 in the
fuel, alcohol has a drying effect on oiled parts, it may wash enough
oil off the cylinder walls to cause lubrication problems at high RPM
and high engine temperatures...

 

When the bike first starts, with the enricher on, both cylinders are
firing and the bike sounds normal. After the motor dies both cylinders
are getting a spark as I try to restart the motor,(verified with a
clamp on timing light). The idle screws don't have an anti tamper plug.
The screw tops require a special "D" shaped socket to adjust. A tool
the local honda dealer says I can't buy.I've filled the fuel lines with
gas ,flush to the top of each line and just let the bike sit for
awhile. The fuel level remains
constant, so I think the float needles are sealing properly. I've
replaced the coils, plug wires, plugs and the ICU but the probplem
remains. Any thoughts?
P.S : What does the converter do? Its between the ICU and the coils
but the Haynes manual dosen't tell me what it does.
Thanks, Barry

 

Carefully feel the exhaust pipes with your hand. If the front pipe is
cold, that cylinder is probably too lean to fire. Pull the spark plugs
and examine them for color and wetness. If you smell gasoline on one
plug but not on the other, the mixture can be too lean to ignite and
you smell
unburned hydrocarbons...

So find a length of steel tubing that will slip over the screw top and
bang one side of it flat with a hammer...

Dirty carburetors? Troubleshooting electric problems by swapping parts
will make the $tealer$hip $mile all the way to the bank, but it leaves
the
parts swapper with little understanding of how the system works and the
wallet becomes rapidly flatter. Can you $ell the ICU and coils that
seem to be OK on eBay?

Do wires from the ignition pickup coils go to the converter? Maybe it's
an analog to digital converter that changes the analog electrical
pulses into bits and bytes so the computer can calculate with them.
That would be called an "AD converter"...

Or maybe it takes the bits and bytes from the ICU, and converts them to
analog pulses and amplifies them so the coil will get a nice hot spark.
See any wires going from the ICU to the converter? That would be called
a "DA converter"...

Or, maybe it's both. AD *and* DA...

For $500, that bad puppy should be able to mix me a martini, not just
warp bits and bytes...

 

I'm sure the converter is a DA converter from the wiring schematic. The
ignition parts I've swapped out have in fact been purchased from Ebay.
Even though I couldn't verify they were perfect I figured they wouldn't
have the exact same problem as my original items.The reason I swapped
electrical items was the condition used to be temporary, occuring only
when I rode in the rain. Advise from another rider suggested dirty
water was being sucked up a vacuum line somewhere and had contaminated
the carburetors somehow.
I'll try fabricating a tool to adjust the idle screws and see what
happens.
Thank you for taking the time to give me some advice.
Barry