TOPIC:

This may sound like a no-brainer, but sometimes the little things are forgotten by over thinking it and assuming that it's a more complicated/serious issue - are the rubber caps for the intake manifold fittings installed and in good shape, and is the petcock vacuum hose connected correctly and in good condition?

MentalMike wrote:

Ok compression test on each cylinder was 150 psi, throttle open, choke out. Plugs were dry and clean. I also pulled exhaust baffles to see if any critters had made a nest in there - all clear.

I turned air screws back to 1 turn out, and started her with starting fluid. After a few attempts, I was able to keep her running with the choke 3/4 to a 1/2 out. I let her warm up holding the choke like this, but even after warm she would still die if I let the choke in. Any touch of the throttle and she would burp and want to die. Idle screw is only set a couple turns out.

Having made sure the pilot circut was completely clear on all carbs, I don't understand why I'm not getting fuel at low idle.

Any thoughts? Thanks.

The good even compression figures are not surprising due to the low mileage. Also indicates rings are doing their job and likely not sticking in the piston groves.

Is there still a good fat spark on the plugs?

Because plugs appear dry, am wondering if fuel level in float bowls is for some reason too low, whereby fuel is not getting to the pilot jet. Would check service fuel level inside the float bowls by performing the clear plastic tube test (may be done without removing carbs from the bike).

If fuel level is obviously too low, there may an assembly issue. Or if the float tabs were adjusted during reassembly using the upside-down measuring method, the float height is likely wrong anyhow.

Good Luck!

Forgot to mention -- would assure integrity of the vacuum line from carb to petcock. Tightly fit at each end. No cracks or splits allowing air intrusion from outside.

When attempting to crank the bike, would put petcock in PRI (prime) position, so as to assure free flow of fuel without worrying about whether petcock diaphram is properly functioning.

Regarding ample supply of clean fresh fuel from tank to carbs --is the tank clean inside (might need flushing to remove any grit or crud suspended and hovering about the petcock intake tube screens up inside the tank)? Are all the petcock screens clean? Is fuel readily flowing from the petcock when in PRI position? Is a good clean in-line fuel filter installed? Am wanting to assure that an ample supply of fuel is reaching the carbs.

As known, if in-line fuel filter(s) are not being utilized, perfectly clean carbs can be instantly re-clogged.

Are the orifices in the float needle seats positively open and clean, so as to permit ample fuel flow into the float bowls?

Are the float needles moving freely inside the seats (and not stuck inside the seats up against the orifices)?

Are the seats loose (lightly snug is okay -- not Godzilla tight)?

Are the clamps tight that hold the carbs into the carb holders?

Is the air filter in place and properly fitted?

Good luck!