Topic: HELP! CB550(500 Tank) Keihin Petcock?

[theletterthomas]

So I recently purchased a 74 cb550 (which has numerous other honda parts on it including a cb500 tank). My petcock has started leaking and I'd like to replace it or repair it. My only problem is that it is not the stock unit. I have attached an image of the Petcock that is connected along with the tank for good measure. It is a Keihin and was wondering if any of you recognize it? Thank you!

[TwoTired]

Looks like a stock Honda type from 75-76 models.
Have you taken it apart yet?  There is an odd size oring in there that probably need replacement.  Measure the old one for a replacement.  Also, these need to be assembled in the correct order and with all the parts; the spring/shim particularly.

This may help:
http://www.cmsnl.com/honda-cb550k1-four-usa_model466/partslist/F++05.html

Check out #4

Cheers,

[Queeg]

both my 76`s had this happen in the last month. i have a new petcock on order from honda. i get it tomorrow or thursday, it if fits. ill get you the part number.
i tried 4 places to find an oring that fit. and the one i did find is tight and is a pain to turn the lever.
Q

[theletterthomas]

Thanks guy's! I haven't taken it apart yet. It' started leaking from the nib that releases fuel to the 1-2 Carbs, but the other nib doesn't leak. Queeg, how much was the petcock your ordered from honda?

[theletterthomas]

Just cracked it open… there was some crud in the hole that was leaking. Cleaned it up and sealed it back up, still leaking... but slower. Time for a new O-Ring.

[theletterthomas]

any word on if the O-ring from honda fit? You know it's not leaking from outside the petcock, it just drips ( slowly ) out of one of the nibs. I noticed that fuel is leaking from the top of the carbs and not coming out of the four gold nibs and you can see fuel leaking from where the hose connects to the fuel filter. Is it possible that bad tubing/ fuel filter is the problem? I'm gonna try and zip tie em later today.

[zanorak]

I have this petcock on my 500 and it always leaks. Very annoying. I'm looking to replace it. I've cleaned it half a dozen times and everything looks "ok" when I put it back together.

[chickenman_26]

any word on if the O-ring from honda fit? You know it's not leaking from outside the petcock, it just drips ( slowly ) out of one of the nibs. I noticed that fuel is leaking from the top of the carbs and not coming out of the four gold nibs and you can see fuel leaking from where the hose connects to the fuel filter. Is it possible that bad tubing/ fuel filter is the problem? I'm gonna try and zip tie em later today.

Your petcock is for a CB500 and is correct for that tank. Order the 4-hole gasket (16955-268-020) from any Honda dealer - list price is $3.56. The disc that's part of the lever assembly often gets distorted somehow. Cure that quickly by rubbing the part on a flat plate covered with 220-grit wet-or-dry. Reassemble. It won't leak anymore.

Stu

[Queeg]

well im back to fallow up. as the gasket is no longer availible,  me and the guy at the honda dealer sat for about 3 hours and 4 days  trying to figure out the outer o ring on the petcock. we came across this. after ordering 2 petcocks from other bikes. and trying to find a cheap alternative.

 part # 16075-ghb-b00
it happens to fit the petcock. mine has been on  for 2 days now and no leaks.
you can find them online. i just googled the part number. about $3.70

[zanorak]

I ordered the 4 hole gasket from the honda dealer a week ago. Number is... 16955-268-020

[theletterthomas]

Queeg thanks! I just ordered one and should be picking it up in a few days. Thanks to everyone who offered their input/help. Greatly appreciated!

[Kemp]

I need the same petcock for my 1975 CB550F. Would anyone know if there is one available? I've tried the parts fische but it's no longer available from Honda and no part number is listed. The inlet stub on the tank is 20mm while most Honda tanks are 15mm so it's really hard to try and cross reference with another model. Any help would be appreciated, even a used petcock would be great!

Kemp

[oldbikeracing]

From what I am reading, a 1975  CB400F, 550F and CB750F's all have 20mm spigots at their fuel tanks.

[RFogelsong]

That's the same one that's on my 1975 550k0 as well. I believe it to be original.  It would make sense as all the other bikes of the same time frame used the same thing (as mentioned by Oldbikeracing). Mine is also starting to leak in the same place although you only notice if you touch it (gets your finger wet).