Murphs' Concours Manual Petcock Conversion Kit

[Mort Canard]

Has anyone had experience with this kit?? Anything in particular to look for when installing it?

 I would like to put the possibility of a hydrolock behind me. 

[Daytona_Mike]

How would that stop hydro-lock?  How do you stop it from hydro-locking  when you turn the petcock to ON?
Your  chances  of hydro-locking  with a manual petcock are  higher than with  an OEM petcock.                                                             We had recent  incident where a person  had just installed a manual petcock and reported that they  severely  hydro-locked  the engine. Bent rod.  Engine is toast.

If your not going to install OverFLow tubes  then the next best thing is go to Murphs and buy a new OEM petcock. You will be   far safer.

[Mort Canard]

How would that stop hydro-lock?  How do you stop it from hydro-locking  when you turn the petcock to ON?
Your  chances  of hydro-locking  with a manual petcock are  higher than with  an OEM petcock.                                                             We had recent  incident where a person  had just installed a manual petcock and reported that they  severely  hydro-locked  the engine. Bent rod.  Engine is toast.

If your not going to install OverFLow tubes  then the next best thing is go to Murphs and buy a new OEM petcock. You will be   far safer.

I spent a lot of years turning the petcock off when leaving the motorcycle. That was standard procedure on my Moto Guzzi, Norton, Triumph, and even an old Honda. I don't think it would be a problem getting back into the habit.

The fuel won't flow past the needle valves fast enough to hydrolock if you turn on the petcock and then start the engine within a minute or two.

OTOH, do you have a link to the procedure of installing overflow tubes in the bowls? 

[m in sc]

ive (sort of) done both. and i agree, i have a garage of vintage bikes so shutting the petock off, for me, is part of the shut down procedure.  that being said, i just added an inline valve. which i was told would be too restrictive. bs. i have it on both my C10s.

I also added  overflows, easy to do. Have actually done that 3 times, for both my bikes and a 3rd set on my buddys.

Of course, i was told by another group i did that wrong as well. 4 years on: zero issues.

overflow tubes: use 4mm brass tube (hobby stores sell them). I think i used a 3.75mm drill bit. drill out bottom of bowl from top in rigid drill press. chamfer hole slightly for lead in, i used green sleeving loctite. MY tubes are about 4-6mm over bowl line, some prefer 8 or 10mm. taller would be safer for sure, but ive had no issues.






i used a 90 degree 1/4"  inline cutoff, you can see it here:


you have to aim the fuel line off the carbs down, run the line across, to the 90, then up to the petcock.  the 1/4" valve works just fine. Have done thousands of miles with it and i don't ride them easy.

i made a small plate that screws to the airbox lid  existing hardware, and pokes out in front of the LH side cover. thats where the valve is located:



you can get the valve anywhere, but this is fine.  https://www.tractorsupply.com/tsc/product/raider-shut-off-valve-1-4-in


or similar.

fwiw, i do still have the stock petcocks on both bikes. both are rebuilt.

[gpineau]

Mine has a manual shutoff but who remembers to turn it off? I had to change the oil and filter  3 times in one week because of carb troubles.  I finally broke down and spent the money. Now I will never have the problem again. It cost about $80 but in my opinion worth it.

https://www.amazon.com/gp/product/B00EP1N39A/ref=ppx_yo_dt_b_asin_image_o01_s00?ie=UTF8&psc=1

[m in sc]

solenoid valves can fail as well. (it's actually what i do for a living, engineer at a valve/actuation company).  I never forget to turn my manual one off.  Its like forgetting to put the sidestand down, to me.   

[cra-z1000]

solenoid valves can fail as well. (it's actually what i do for a living, engineer at a valve/actuation company).  I never forget to turn my manual one off.  Its like forgetting to put the sidestand down, to me.   

Great....now someone will find a way to connect the petcock to the sidestand to not forget...😂

[m in sc]

small linear actuator powered off the side stand switch to operate a full flow ball valve.    (kidding, kidding) 

[Boomer]

Great....now someone will find a way to connect the petcock to the sidestand to not forget...😂

Worse still, what if ya center stand her? 

Overall, the best system is to use the OEM vacuum petcock, but to fit overflow tubes, just in case of the failure of the petcock at the same time as a float needle is stuck open, or like gpineau convert her to EFI. 

[VirginiaJim]

I've had one bike with a manual petcock.  I was always forgetting to turn it back on assuming I remembered to turn it off.   Best way I've found to avoid that is FI.

[m in sc]

FI has its failings as well. I have a friend, right now, chasing issues with his older sprints fi. high pressure fuel spraying at the coil packs is not my idea of fun either.    But i do love an FI bike.

If you notice on mine, the fuel valve is in plain sight. Buried under the tank will def make it a bit more easy to forget.   again, I have a manual valve and the stock vacuum petcocks, rebuilt, working together. even if i forget to turn off the manual valve, the vacuum petcock will hold it better than nothing.  also, having both tanks lined with caswell removes the rust possibility, which is usually what causes failures in the 1st place. .

[Mort Canard]

Thanks guys.  I will put in the overflow tubes and a new petcock.  Hopefully should solve the problem permanently.

[DC Concours]

You sir are quite talented. I looked at mine and thought I could do it too, but it needs some precise handy work.

overflow tubes: use 4mm brass tube (hobby stores sell them). I think i used a 3.75mm drill bit. drill out bottom of bowl from top in rigid drill press. chamfer hole slightly for lead in, i used green sleeving loctite. MY tubes are about 4-6mm over bowl line, some prefer 8 or 10mm. taller would be safer for sure, but ive had no issues.

[George R. Young]

Drain tube installation:
https://web.ncf.ca/ag136/floatDrainTubes.htm

[m in sc]

You sir are quite talented. I looked at mine and thought I could do it too, but it needs some precise handy work.

Thanks, i appreciate that.

you can always send them to Steve to do.

[DC Concours]

I did. Mine was done by Steve. I was looking at doing it myself b/c it looked simple enough but I realised I was not equipped and didn't want to end up busting the bottom off. I even bought a variety pack of copper tubing from a local hobby store.

[DC Concours]

You sir are also a talented man. I never knew you could epoxy it! Is it still holding after all these years?

Drain tube installation:
https://web.ncf.ca/ag136/floatDrainTubes.htm

[George R. Young]

You sir are also a talented man. I never knew you could epoxy it! Is it still holding after all these years?

I sold it in 2019 and things were working fine then. The tubes were a light press fit and the epoxy was very thin, there to seal more than to provide strength.