Have to replace gas disconnect (the part that goes

Question edited for a lot more clarity, plus typos.
Question moved from 'Gas Motorcycles' to model category.

You need to track the buzzing, but these come in either carburetor or Electronic Sequential Port Fuel Injection (ESPFI) My guess is that yours is fuel injected and the buzzing is the fuel pump relay.

2000 fuel injected road king won't start

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Aug 14, 2017 - You state: bike cranks and starts when fuel is placed inside the cylinders then based on the limited information available it reads fuel related ...

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I have a 2008 Road King Classic (and have had the tank off), so maybe they're similar.
Disconnect the negative lead of the battery.

My dash has a screw under the nose of the seat (which must be removed) and one in the front.
lift dash and unplug harness.

If you have a gas gauge in the left hand gas cap, underneath tank unplug it's connector.

The fuel line has a quick disconnect. Pull fitting, and line unplugs.
There is a check valve inside to keep gas from leaking, but it's a good idea to have a catch cup, just in case some residual fuel flows out.

From there, I have a bolt on each side of the front of the tank, one in the center rear, then lift it off.

That will be either the front or rear switch sticking, first try unpluging the front brake light switch, with this disconected if the light stays on the problem is with the rear switch, locate the switch this will be close to the brake pedal normal spring opperated which can stick, check it is closing fully, you may also disconnect the switch and check the light goes out reconnect the front switch and check correct opperation, this would thenpoint the fault towards the rear switch

Yes, there are, unfortunately the easiest way to replace them is to remove the old one and match it up to a replacement.
A quick note here is that often it is not the O-ring, sadly it is the connector hose and or the coupling on the fuel tank. So if replacing theO-ring does not help, then you may need to replace those items.

The problem is valve timming, recheck the valve timming. Hope this helps!

the fuel pump for your 2000 fuel injected road king is located in the fuel tank. you will have to remove the speedometer housing, by first removing the seat, then remove the one small screw near the seat that holds the speedometer housing in place, also remove the small screw at the front of the speedometer housing and lift the housing off the tank and disconnect the wiring that goes to the back of the speedometer. there is a large oval shaped gold in appearance plate on top of the fuel tank. this plate is what the fuel pump is mounted to.