Topic: 1976 CB550 19mm Petcock Money Saving Solution

[SPAM]

I needed to replace a leaking petcock for my 1976 CB550K. This particular bike has an annoyingly unpopular 19mm bunghole. As I understand I had three options:

1- A petcock "kit" ($30, DSS). I was not sure this would address my leak.
2- A NOS petcock ($100, ebay).
3- A single-output, 19mm-bungholed CB750 Petcock ('75-'76 I think) with a fuel line splitter ($75, ebay).

For $40, I found a 19mm single-output CB750 petcock here: http://www.cb750supply.com/products/6/fuel-system/67/petcock-parts-fuel-line (parts # 16950-341-671).
1/4" Fuel line splitters (Y fittings) are $5 shipped all over the web.

I saved some money. This post may save others money and time.

If others have used this approach with success or failure, I'd welcome your advice. I will report back upon installation and testing.

[db22]

Oh boy, I had the same issue last year when my 19mm petcock did the same thing. Found a NOS for about $50. I do have a spare tank (same damn 19mm bung) -- how difficult is it to cut the old bung out and have a new, standard-size one welded in? Seems like you'd have to be pretty careful welding on that thin sheet metal.

[Bankerdanny]

The problem is FINDING a replacement bung to weld in. The tank that came with my 77 550F bsaket case had the bung cut off flush with the bottom of the tank.

I finally bought a replacement 3/8" steel bung off eBay from a guy here in Illinois  ($8 shipped)and used a drill to cut out the remains of the bung from the tank. I haven't had the new one welded in yet, but I am not anticipating any real problems. Then I will need a petcock, but this is a common size for Harleys (which is why I decided to go this route) and readily available for about $15.

[Retro Rocket]

I wouldn't weld the bung in , I would have it brazed in....

[db22]

Yep, I think brass brazing might be the bet bet. Do welders commonly do that? I'm familiar with it from seeing it on bicycle frames, but I've never seen it done. It joins the frame tubes without damaging the steel.

[Retro Rocket]

Yep, I think brass brazing might be the bet bet. Do welders commonly do that? I'm familiar with it from seeing it on bicycle frames, but I've never seen it done. It joins the frame tubes without damaging the steel.

Most plumbers can braze, most welders should at least know how to...