Info on electric fuel cutoff valve

[Quince]

"AFC-121 electric fuel cutoff valve" I've seen this pop up in some of the posts related with carbs rebuild. Can somebody educate me on why will this addition be necessary and history of the issue? Thank you.

[HayHauler]

The only thing I can think of is that it shuts off the fuel flow when the key is turned off.  This keeps you from "remembering" to shut it off yourself.

Hay 
Jimmyt

[Joe333x]

"AFC-121 electric fuel cutoff valve" I've seen this pop up in some of the posts related with carbs rebuild. Can somebody educate me on why will this addition be necessary and history of the issue? Thank you.

Exactly as stated, you connect it to 12v switched power so that it opens and closes when you turn the key. Less likely to have hydro-lock happen. Pairs great with a non vacuum petcock.

[Quince]

So, theoretically unless somebody was messing up with the hoses, if issue was discovered and solved by 1988-1989, none of the 1500 Valkyries (including my 2000) should have a hydraulic lock event. However, I'll keep turning gas off even so I never did on any of my other bikes ever.

[WintrSol]

In the case of a stuck float valve and open petcock, the flow rate can easily overcome the overflow drain. The PO installed one when he also installed the belly tank, not because fuel normally flowed through the fuel pump on the tank, but because they can possible stick open, too. Fuel tube routing is very important if not using a pump, for the reasons Honda mentioned in the quote above.

[Joe333x]

So, theoretically unless somebody was messing up with the hoses, if issue was discovered and solved by 1988-1989, none of the 1500 Valkyries (including my 2000) should have a hydraulic lock event. However, I'll keep turning gas off even so I never did on any of my other bikes ever.

There is a guy named Dave Wilder that is a member of the Valkyrie FB group, he owns https://www.valkyrieflatsix.com/. He is the one who I got a lot of my information from and he has rebuilt more Valkyrie carbs than anyone on earth I'd imagine. He suggests using the electric fuel shut off along with a non vacuum petcock. The vacuum on the petcock can fail so you are taking that out of the equation, then add the electric auto shut off and you don't have to worry about fuel dumping into the carbs which can increase the risk of hydro-lock. If fuel cannot get into the carbs it drastically lowers the chances. Many Valkyrie 1500s have had problems with hydrolock and it ends up requiring replacement of the starting gear since it will break off a tooth and it's a major job. What ever you do please take advice from people who know what their talking about. Two major things Valkyries suffer from are leaking carbs and hydro-lock.

[WintrSol]

If you do go for the shutoff, make sure you get the one with the larger ID, as the other one will starve the engine at high loads and rpm.

[Joe333x]

If you do go for the shutoff, make sure you get the one with the larger ID, as the other one will starve the engine at high loads and rpm.

This is the one I'm running. Works great.
https://ebay.us/m/taLV4t