Topic: Fricken petcock is hitting my CR26 carb!

[FunJimmy]

OK,I did the obligatory search and couldn't find the answer to my dilemma so I’m calling on the wisdom of the collective.

Been working on the installation of an amazing rack of Keihin CR26 carbs on my ’77 CB550F, and after a lot of F’ing around making special manifolds and such, I discover that the petcock is resting on the left carb.

The interference with the petcock also prevents me from turning it to the “ON” position.

Does anyone have a small petcock solution to this? Maybe an elbow fitting that I can connect the hose to and then use an inline fuel tap or something?

Thanks
FJ

[tweakin]

Mine also hit but not that bad.  Just the outlet tube so I turned mine out a bit to clear until I can come up with a better solution.  I will be watching to see what you come up with.

[754]

 A few maybe things..
 Shorten up nut, or  machine threads on petcock longer.

 Shorten threaded bung coming out of tank.

 Make new selector, with rib centered (part you turn to get gas flow)
 
 Shim up rear of tank...

[domer]

maybe a pingle? cant seem to find dimensions on them though... i like 754's idea of shortening the bung... looking at mine i could get away with a shaving 1/8-1/4"

[Godffery]

Hey Fun Man,
Easyest solution I can think of would be the "elbow fitting and in-line fuel tap " you could make an adaptor by turning down a solid peace of brass to fit as a Petcock blank (using the stock nut to fasten it in place) then drill & tap a thread to fit a standard brass 90 you find at your local hardwhere store.   LMK if you'd like a drawing.

[sparty]

I had the same problem - I cut about 1/2" off the front rubber tank mounts, it helped move my tank about 1/2" forward and the petcock cleared.

Sparty

[Kanticoy]

Hey FJ, I think I've got it.  Z1 has a petcock adapter nut for our tanks which use a 20mm metric petcock.  This adapter makes it adapt down to 1/4 NPT.  Once you have adapted to that size, the sky is the limit with hardware store fittings to angle the line wherever you want it to go.  I am gonna order one myself and use and inline shutoff just like you mentioned.  Kinda glad you sparked my research interest.  Never knew these were out there.

http://www.z1enterprises.com/products01/Petcock-Adapter-Nut-20mm-14-NPT.aspx

[kos]

Your a machinist...do the proper thing and machine new manifolds so you have the correct clearance. It's only time?

KOS

[swellguy]

I don't know of this is helpful but I did notice today that Sudco has a number of new "retro" dual outlet petcocks to fit most Japanese bikes:



It's their carbs that are causing the problem, maybe one of their petcocks can help:

http://sudco.com/fuel.html

[FunJimmy]

Hey Fun Man,
Easyest solution I can think of would be the "elbow fitting and in-line fuel tap " you could make an adaptor by turning down a solid peace of brass to fit as a Petcock blank (using the stock nut to fasten it in place) then drill & tap a thread to fit a standard brass 90 you find at your local hardwhere store.   LMK if you'd like a drawing.

Godfrey

That’s the direction I was thinking too. I’m gonna make the petcock blank from aluminum with a pressed in (and epoxy) stainless steel hose barb at 90 degrees. Then the inline fuel tap can be located somewhere along the line.

Hey FJ, I think I've got it.  Z1 has a petcock adapter nut for our tanks which use a 20mm metric petcock.  This adapter makes it adapt down to 1/4 NPT.  Once you have adapted to that size, the sky is the limit with hardware store fittings to angle the line wherever you want it to go.  I am gonna order one myself and use and inline shutoff just like you mentioned.  Kinda glad you sparked my research interest.  Never

Kanticoy

Thanks for looking into it for me. Unfortunately my 55 tank has an M16 x 1.5 threaded bung on it and Z1 only has a 20mm or an 18mm adapter available.

Your a machinist...do the proper thing and machine new manifolds so you have the correct clearance. It's only time?
KOS

KOS

LOL, thanks for that!
Anything made on the lathe is pretty easy for me, but you’d laugh your arse off if you knew how crude my milling tools where.



Thanks everyone for some excellent solutions.

FJ

[bwaller]

Hey FJ, Z1 or Sudco have better inline cock options than I mentioned.

[Kanticoy]

I'm still looking too FJ...actively.  I know I will run into this eventually, so my pain is your pain!

[754]

Jimmy, I can make you an adaptor, but assume you like to have reserve.
 Them Sudcos, wonder if they are real PINGEL or knockoffs.. .. dont ever recall seeing an unplated PINGEL  before!

 Wonder what happened to the Rickman guy that ended up drilling into his tank .. looked like a Pingel would have fit..

[Bluegreen]

Move it an inch forward?

[FunJimmy]

Move it an inch forward?

Certainly a possability but, requires a repaint of the tank.

[754]

Jimmy, can you;
 rotate petcock outlet, away from frame at 45 or 90 degrees.. wont look the best , but may werk.
 or put 2mm spacer & gasket,  between manifold and carbs.

 "your" parts should be loaded today, and heading out west shortly..

[Ernest T]

Jimmy, can you;
 rotate petcock outlet, away from frame at 45 or 90 degrees.. wont look the best , but may werk.
 or put 2mm spacer & gasket,  between manifold and carbs.

 "your" parts should be loaded today, and heading out west shortly..

Thats a good idea.

[Tintop]

Hey FJ, also most had the same issue with my setup.  Only in my case it was the intake tappet cover on #1.  Only thing that saved it was its a TTR4 alloy with the dish.  Bottom of the petcock just clears.

Moving the tank forward is quite easy, and it looks like you only need maybe 1/4".  I moved mine forward (hind sight says 1/4" too far ) by cutting off the front tank mounts on the frame.  Then drilling a new hole through the frame, and welding in a piece of rod farther forward.  I moved mine 1/2"+ so I needed a new rear mount too.  You should have to go that far.

[754]

 I think with the modern forks, he may not  be able to slide the tank forward, I was thinking..

[FunJimmy]

I think with the modern forks, he may not  be able to slide the tank forward, I was thinking..

Actually, I spent a lot of time making and fitting the cafe seat to the tank and I would prefer to move the carbs farther back, but I'm currently working on a minimal hose fitting off the tank with an inline fuel tap first.

[diskman]

I just turned my petcock a tad so the lever is facing more forward.  Worked great and 0$.

[turboguzzi]

I think with the modern forks, he may not  be able to slide the tank forward, I was thinking..

Actually, I spent a lot of time making and fitting the cafe seat to the tank and I would prefer to move the carbs farther back, but I'm currently working on a minimal hose fitting off the tank with an inline fuel tap first.

indeed, i found a simple nipple to attach to the tank and run a dry break/quick release fitting on my racer. sure, that's a crude/race only solution, so fit an online tap and bolt it to your manifolds....plenty of meat there for a 6mm threaded hole

[MRieck]

Hey FJ, I think I've got it.  Z1 has a petcock adapter nut for our tanks which use a 20mm metric petcock.  This adapter makes it adapt down to 1/4 NPT.  Once you have adapted to that size, the sky is the limit with hardware store fittings to angle the line wherever you want it to go.  I am gonna order one myself and use and inline shutoff just like you mentioned.  Kinda glad you sparked my research interest.  Never knew these were out there.

http://www.z1enterprises.com/products01/Petcock-Adapter-Nut-20mm-14-NPT.aspx

The last time I used one of those it was not a true 20mm thread. That was a long time ago. It seemed like some kind of Rube Goldberg fit that would destroy the tank bung in the end. Maybe Pingel got their stuff together???

[Bluegreen]

Move it an inch forward?

Certainly a possability but, requires a repaint of the tank.

Should be fine if you fill the tank with water for the welding, no?