Topic: 1972 CB500 - Gas tank retrofit - what others will work ?

[danielzink]

Hey All,

New guy to the forum.

New 1972 CB500 owner and I have a quick question.

Do other year/displacement gas tanks fit without modification ?

Thanks, Dan

[whitjonw]

Why do you ask, I wonder ?

[BPellerine]

there is one year cb650 tank that looks good.

[danielzink]

Why do you ask, I wonder ?

to keep the thread on point...please feel free to contact me with individual questions....

Otherwise...the original tank is in a state of disrepair...

Would a 1975 CB550 tank fit ?

Maybe a 1976 Cb400 tank ?

Upon researching...the 'bay....a specific search for "1972 CB gas tank" turns up a pretty slim selection...

Thanks for everyone's replies so far..

[whitjonw]

I fitted a '74 550 tank to my'73 500. Same tank through 1976 for the K series. In fact, when I changed my search to 550 that's when I found my tank as there were a whole lot more tanks available using 550 in the search.

[danielzink]

yes to a '75 550.
I should amend my earlier reply that any 500/550 tank from a 4 cylinder 500/550 will fit. The 500 Twin is a slightly different beast.
You certainly can make other tanks fit, but it will require some fab work. But the 500/550 is a plug-and-play solution. 

I fitted a '74 550 tank to my'73 500. Same tank through 1976 for the K series. In fact, when I changed my search to 550 that's when I found my tank as there were a whole lot more tanks available using 550 in the search.

Perfect. Thank you both so much !

[Scott S]

 Be aware that the petcock changed over the years. Somewhere around '75-76, Honda went to a one year only version that was prone to leaking and is not rebuildable. If you get a tank that uses that threaded on petcock (versus the kind that bolts on with two screws), be prepared to spend $100 on a new petcock. Factor that in when buying a replacement tank.

[SOHC4 Cafe Racer Fan]

Be aware that the petcock changed over the years. Somewhere around '75-76, Honda went to a one year only version that was prone to leaking and is not rebuildable. If you get a tank that uses that threaded on petcock (versus the kind that bolts on with two screws), be prepared to spend $100 on a new petcock. Factor that in when buying a replacement tank.

Yep. The 1975 CB750K has that petcock.  Pricey for the OEM Honda petcock and it's not readily available.  You need to keep your eye out on eBay for a NOS one.

[754]

The 400 tank wilm probably fit and have more room underneath than the 500 tank.

[RAFster122s]

I wonder if a CX500 tank would fit. I'll have to check that... have both.

[Johnie]

Let me know if you think any of these will help you out? Got them from a closed Honda dealer.

[whitjonw]

Perfect. Thank you both so much !

You are welcome and good luck in your search !!

[roach374]

Sorry to reawaken a zombie thread, but I'm in the same boat. @danielzink, did you find a CB550 tank that fit? Confirmed that the length of the tank is different and the seat needs to be farther back?

[bryanj]

Thats only if you use K3,  K0 to K2 are OK except petcock. Never tried F

[RAFster122s]

F tank and late K tank with lid over fuel cap have different length seat...

[Bankerdanny]

An F seat will work with a K tank,  but there is a gap between the tank and the seat. The F tank only works with the F seat,  to use a K seat you would have to figure out how to move the hinge.

[XC204]

Of its a modified bike (different seat) a cb650 tank fits with a few more front mount posts and rubbers need shortening ,I made a new rear mount (tank is longer) and I tucked the coils in tighter by modifying the stock coil mounts because tank has narrower tunnel.