Topic: CB500 Carbs

[Parepin]

Hey guys, got linked this way from the Advrider forums with a question in hand. I'm currently rebuilding a 1972 CB500 four and the carbs are nasty. One has a broken float mounting post, and another is corroded beyond repair (I think). Anyway, i jumped on Ebay lookin for some carbs and CB500 specific carbs are few and far between, and are going for quite a chunk of change. cb550 carbs, however, are all over the place. Does anyone happen to know if, for example, a 1976 CB550 shares the same carb body (not the needle or jets) as a CB500? They look identical, but when trying to compare part numbers I see that they are different. Any help would be appreciated.

[pdxPope]

 

Oh boy....

Firstly, welcome aboard.

Secondly use the search function. It's that little rectangle in the upper rt. hand corner with the picture of the magnifying glass next to it. Type in CB500 carbs.

All of your questions will be answered.

-JP

[Bill Vaughan]

This may help

[78 k550]

Welcome,

You should check the for sale parts ssection out.

Paul

[78 k550]

opps I didn't put them up. I have a set of 627B 50.00 + the ride.
See how hard that was find a set. lol
Or if you would like to pay more?

Paul

[Parepin]

Holy crap, that was fast.

Thanks for the welcome, folks. I did briefly search the forums, but the fact that I don't really know what exactly I'm searching for leaves me with empty hands. The fact of the matter is this is my first rebuild, and really the only time I've ever tinkered with a motor this old, so I barely know what I'm doing as is.

Thanks for the chart, Bill. Again, not really sure what I'm looking at, but I interpreted that to mean that the CB550K 74-76 carbs are, infact the same (short of jets, needle, etc.) Is this correct?

[Cowboy]

Hey Parepin (MasterKayin),

Glad you found a quick response here. If you happen to need BMW Airhead info, OldSkool over at Adventure Rider is the place to get it. If you need info on Hondas (and not just SOHC4s) you'll find it fastest here. If you just want to shoot the breeze about old bikes, both forums are great!

I hope you find what you're lookin' for and get the old girl back on the road!

[Bill Vaughan]

Parepin,

It looks that way to me (both Type I bodies), but I have no experience with the 500's - only 550's.  There could be subtle differences.  I'm sure someone familiar with the 500 models will come through with the right answer.

By the way, I found this chart on the forum quite some time ago.  Glad someone took the time to assemble the information in one place.

[SteveD CB500F]

The carb bodies are the same - just the neddles and jets are different for the 550.

There's a detailed thread on here somewhere on how to repair broken float mounting posts as it's easy to break them when removing the pivot pin.