Fuel Petcock

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Ragmanx1
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Fuel Petcock

Postby Ragmanx1 » Sat Jan 30, 2016 10:01 pm

Why do so many guys change out their stock fuel petcock for after market or other brand?

SteveG
2012 Ural Patrol

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Peter Pan
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Re: Fuel Petcock

Postby Peter Pan » Sat Jan 30, 2016 10:42 pm

or just modify it?
viewtopic.php?f=12&t=32639&p=405674&hilit=convert+vacuum+valve+to+manual#p405674

Simple>
If you have a IR temperature sensor gun you can see it by yourself...both cylinder head temparatures and exhaust temps are way off and on full throttle on a slope or with head wind your gasoline flow continues and will not start to starve.
As soon you have a manual petcock those issues become histories of the past.

Sven
Sophie Travelair
Patrol 2013 with quite a few add-ons from Jim Petitti.(RIP)
8 weeks 12.000km Oregon - Alaska - Oregon, Engine broke free at 21.000km now in CR 37.000km and counting.
With a DIY foam air filter the rig runs well even in tropical rain. The air box looks then like an aquarium. :moto:
Final drives: 1. at 5000km, 2. at 34.000km(+friction plates)

The Avatar are 2 rice grains stating life's essence:
"The most important you cannot see!"
=> Attitude makes the difference!

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chaos2
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Re: Fuel Petcock

Postby chaos2 » Sat Jan 30, 2016 10:55 pm

in other words, the stock petcock operates automatically via a vacuum line. If the line leaks it can cause the left cylinder to run lean and overheat. Or with the throttle wide open and reduced vacuum it may not flow enough gas. If the petcock malfunctions and the carb float valve leaks, the cylinder could fill with fuel leading to hydraulic lock and a bent crankshaft if you try to electric start it. The manual petcock is cheap and trouble free. Just have to remember to turn it on and off.
Last edited by chaos2 on Sat Jan 30, 2016 11:03 pm, edited 1 time in total.
past afflictions include TR motocars and bikes, R60/2 & a R65, MGs, and a Citroen.
Now a 2012 FF GU and an 87 K75s
dual K&N cones on PVC intake, 40/137.5
Raceway needles
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Albuquralque
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Re: Fuel Petcock

Postby Albuquralque » Sat Jan 30, 2016 10:57 pm

I've owned four Urals with the vacuum petcock and all four have failed. Meaning even with the engine off (no vacuum) the petcock allowed fuel to flow down to the carbs.
"Put a little gravel in your travel"

Darrell - Albuquralque
2014 Patrol - Babe the Blue Ox
EFI Map OR 1.02
Throttle Body Vacuum Ports
K&N Air Filter
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Previous Urals Owned: 2004 Wolf, 2006 Tourist, 2006 Patrol (TOW), 2006 Patrol (TOM)

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SidecarDan
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Re: Fuel Petcock

Postby SidecarDan » Sat Jan 30, 2016 11:52 pm

I was having vacuum issues and was not getting enough gas to keep the right cylinder happy and was getting back firing and popping on the right. Changed to a Yamaha petcock and have not had any issues other than forgetting to turn it back on when I get on the bike.
Dan
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Yamaha petcock

stagewex
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Re: Fuel Petcock

Postby stagewex » Sun Jan 31, 2016 8:58 am

Albuquralque wrote:I've owned four Urals with the vacuum petcock and all four have failed. Meaning even with the engine off (no vacuum) the petcock allowed fuel to flow down to the carbs.


I have only had one (1) Ural over the last 9 years and still run the same original stock vacuum petcock. I have moved it 3 times from different types of fuel tanks. Have never had a problem except when I have left it on "PRI" because I'm an idiot. Same thing can happen with the Yamaha it you leave it "ON".

When and if it does fail I will probably change to the Yamaha. I guess I'm just so used to it and I don't like to mod things that already work. If yours has a problem them by all means change it.
Stagewex

2007 Ural Patrol, 2006 Yamaha TW200, 1995 BMW K75, 1969 BMW r60/2US

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chaos2
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Re: Fuel Petcock

Postby chaos2 » Sun Jan 31, 2016 11:38 am

after 25 years with a fuel injected bike and 2 years with the vacuum petcock it took a while for me to remember to turn the thing on an off. Fortunately my carb float valves never leaked and I always kick start the thing (flaky RPOS e-starter)
past afflictions include TR motocars and bikes, R60/2 & a R65, MGs, and a Citroen.
Now a 2012 FF GU and an 87 K75s
dual K&N cones on PVC intake, 40/137.5
Raceway needles
Modtop exhaust
$29 VW Hydraulic steering dampener

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Ragmanx1
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Re: Fuel Petcock

Postby Ragmanx1 » Mon Feb 01, 2016 8:12 pm

I bought a one on line for about $8 and free ship.
The stock one on my '12 Patrol works fine. I have a good fuel filter on both carbs and run non-ethanol gas.
I think I'll carry the replacement in my tool box. Pushing 71 years, I know I''ll forget to shut it off every time.
Kinda a catch 22 deal.
Thanx for all the help.
SteveG
2012 Ural Patrol

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harryball
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Re: Fuel Petcock

Postby harryball » Wed Feb 03, 2016 10:46 pm

Here is my solution with the Yamaha 2GU-24500-02 which I got on Amazon for about $25 + $5 shipping. It was the last one for that supplier, looks like they are a few $$ more now but still not bad. I show what I had to do to modify it.

---
2008 - Tourist - "Ursula" / 30mpg / 32k as of 9/2017
2010 - Patrol - "The Rattler" / 32 mpg / 53k as of 9/2017
K28 tires on both rigs, pusher gets about 6000 miles give or take.
3/8" toe in and 2.5 degree lean
Robert
http://HabitatForBats.org - Give a bat a home!

mouka
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Re: Fuel Petcock

Postby mouka » Thu Feb 04, 2016 7:58 am

harryball wrote:Here is my solution with the Yamaha 2GU-24500-02 which I got on Amazon for about $25 + $5 shipping. It was the last one for that supplier, looks like they are a few $$ more now but still not bad. I show what I had to do to modify it.



Cheap Chinese knock offs sell for $8 shipped to your home. They work just as well as original Yamaha's.
2005 Honda Sabre 1100
2003 Ural Tourist
1998 Honda Aero 1100

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harryball
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Re: Fuel Petcock

Postby harryball » Thu Feb 04, 2016 9:38 am

mouka wrote:Cheap Chinese knock offs sell for $8 shipped to your home. They work just as well as original Yamaha's.


My problem with "Cheap Chinese knock offs" is the components they use. They may work great out of the box... but what about a year from now? Try an experiment, go to a truck stop and purchase some black rubber bungees made in America. Then go find and buy some "identical" cheap Chinese knock offs. In about a year, or less, of use you will discover why the cheap ones are cheap. I'd rather not come back to find my fuel on the ground or in the cylinders when the rubber components disintegrate inside the petcock. Will that happen? I don't know, maybe they come from the same line and are just stolen from standard production and sold cheap, but there is not enough difference in price for me to want to take the chance.

My second problem is property and intellectual theft. I've been the victim of it, I do my best not to support it. There is a very good chance, like 101% chance, that those petcocks are a stolen reverse engineered design and a reasonable chance they are stolen property right off the Yamaha production line somewhere. That is why I asked, what part number is on the petcocks and there is none. Never stamped or ground off or ground off the molds.

You guys do what you want but I'm telling you, WATCH THEM CLOSELY, if they used cheap Chinese knock off rubber o-rings in those cheap Chinese knock off petcocks that $15 or so savings could be lost in one tank of fuel.
---
2008 - Tourist - "Ursula" / 30mpg / 32k as of 9/2017
2010 - Patrol - "The Rattler" / 32 mpg / 53k as of 9/2017
K28 tires on both rigs, pusher gets about 6000 miles give or take.
3/8" toe in and 2.5 degree lean
Robert
http://HabitatForBats.org - Give a bat a home!

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Peter Pan
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Re: Fuel Petcock

Postby Peter Pan » Thu Feb 04, 2016 10:03 am

I had to smile about Harry's last comment...Story of my life too!
+1

By the way the manual petcock needs one thing. = do not become too lazy.
I am used to keep it all the time open.
My son Thomas experienced an interesting adventure yesterday... after a 1 1/2 hour ferry voyage...right cylinder was flooded and hydro locked.
Plus the right carb gave him interesting "insights" until the night.

Part of life and needed training for a future pilot.
Sven
Sophie Travelair
Patrol 2013 with quite a few add-ons from Jim Petitti.(RIP)
8 weeks 12.000km Oregon - Alaska - Oregon, Engine broke free at 21.000km now in CR 37.000km and counting.
With a DIY foam air filter the rig runs well even in tropical rain. The air box looks then like an aquarium. :moto:
Final drives: 1. at 5000km, 2. at 34.000km(+friction plates)

The Avatar are 2 rice grains stating life's essence:
"The most important you cannot see!"
=> Attitude makes the difference!

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harryball
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Re: Fuel Petcock

Postby harryball » Thu Feb 04, 2016 12:27 pm

Peter Pan wrote:I had to smile about Harry's last comment...Story of my life too!
+1

By the way the manual petcock needs one thing. = do not become too lazy.
I am used to keep it all the time open.
My son Thomas experienced an interesting adventure yesterday... after a 1 1/2 hour ferry voyage...right cylinder was flooded and hydro locked.
Plus the right carb gave him interesting "insights" until the night.

Part of life and needed training for a future pilot.
Sven


Yep, now that I have broken the habit of turning the petcock to "PRIME" when I get off due to my habit for turning it OFF... gotta rebuilt that habit and back it up as well. I was thinking about adding a decal on the dash/speedo "Fuel OFF?" or something to try and prompt me as a reminder.
---
2008 - Tourist - "Ursula" / 30mpg / 32k as of 9/2017
2010 - Patrol - "The Rattler" / 32 mpg / 53k as of 9/2017
K28 tires on both rigs, pusher gets about 6000 miles give or take.
3/8" toe in and 2.5 degree lean
Robert
http://HabitatForBats.org - Give a bat a home!

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Peter Pan
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Re: Fuel Petcock

Postby Peter Pan » Thu Feb 04, 2016 10:26 pm

Not necessarily its needed to switch off on daily riding base. Just when you will leave her standing for long time or when she will get rocked. like on a trailer or ferry, then to lock off is a good habit.
I have the habit to keep the gasoline valve on most bikes continuously open for the last 30 years with the good result that the bowl needles are better seated. ...only trouble causers were NSU, MZ, Jawa.
Sophie Travelair
Patrol 2013 with quite a few add-ons from Jim Petitti.(RIP)
8 weeks 12.000km Oregon - Alaska - Oregon, Engine broke free at 21.000km now in CR 37.000km and counting.
With a DIY foam air filter the rig runs well even in tropical rain. The air box looks then like an aquarium. :moto:
Final drives: 1. at 5000km, 2. at 34.000km(+friction plates)

The Avatar are 2 rice grains stating life's essence:
"The most important you cannot see!"
=> Attitude makes the difference!

User avatar
Ragmanx1
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Re: Fuel Petcock

Postby Ragmanx1 » Mon Feb 08, 2016 2:03 am

A fellow Comrade on the "Modifications" section found this vacuum petcock on Amazon. $6.90 with shipping.

http://www.amazon.com/gp/product/B008YC ... ages00#Ask

I also know if I get a simple (on/off/reserve) replacement I will forget to shut it off. :oops:

It looked good and ordered one. May be a good replacement or spare.

SteveG
2012 Ural Patrol


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