Author Topic: Which carbs to connect to which port on a 2 port 750 K0 petcock?  (Read 555 times)

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Offline Scootch

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After refurbish and working with the petcock on my bike I have come to realize that there seems to be quite a bit more to the lowly petcock than just a valve. I read some of the missives that have been written in this group. So one of my questions is in the title. Another one is if anyone has a "schematic" for the double outlet petcock? I'd like to understand how the fuel travels through it under the normal and reserve conditions.

Online bryanj

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Re: Which carbs to connect to which port on a 2 port 750 K0 petcock?
« Reply #1 on: November 16, 2023, 03:57:01 PM »
Both outlets are connected inside the petcoke and will supply both mai, via the brass tube, and reserve, bypassing the tube.
It does not matter which pipe connects to which outlet
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Offline The Lone Builder

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Re: Which carbs to connect to which port on a 2 port 750 K0 petcock?
« Reply #2 on: November 19, 2023, 04:50:42 AM »
Here are a couple of pics that might help.

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Offline Scootch

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Re: Which carbs to connect to which port on a 2 port 750 K0 petcock?
« Reply #3 on: November 19, 2023, 05:46:25 AM »
Thank you for the pics!

Online Don R

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Re: Which carbs to connect to which port on a 2 port 750 K0 petcock?
« Reply #4 on: November 19, 2023, 08:56:58 PM »
 What blew my mind was realizing the petcock to tank screws need proper washers to seal them or the petcock will leak through. 
No matter how many times you paint over a shadow, it's still there.
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Offline Scootch

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Re: Which carbs to connect to which port on a 2 port 750 K0 petcock?
« Reply #5 on: November 20, 2023, 04:37:24 AM »
What blew my mind was realizing the petcock to tank screws need proper washers to seal them or the petcock will leak through.
Yes exactly. Mine was leaking. PO had used copper washers and they were large. When I rebuilt I used the fiber washers. It still tended to leak a small amount. Turns out I needed to torque the screws a bit more. So far it is not leaking. Fingers 🤞

Online bryanj

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Re: Which carbs to connect to which port on a 2 port 750 K0 petcock?
« Reply #6 on: November 20, 2023, 06:01:50 AM »
Don, a lot of people have been caught out by those washers
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!

Online Don R

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Re: Which carbs to connect to which port on a 2 port 750 K0 petcock?
« Reply #7 on: November 20, 2023, 06:18:30 AM »
 A lot of the replacement petcocks on ebay come with lock washers shown in the pictures, I suspect there are a lot of frustrated buyers.
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline Scootch

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Re: Which carbs to connect to which port on a 2 port 750 K0 petcock?
« Reply #8 on: November 20, 2023, 06:39:42 AM »
A lot of the replacement petcocks on ebay come with lock washers shown in the pictures, I suspect there are a lot of frustrated buyers.
That's why I learned quickly not to be penny wise and pound foolish. Get genuine Honda parts from places like South Sound Honda or Yamiya or equivalent. Saves in the long run.