I will shamefully admit, I feel a bit of an idiot right now. Against all better judgement I went ahead and vinyl wrapped a tank I purchased quite reasonably off ebay. Bought a locking mechanism for it even, got everything ready to put it back together, and it was looking sweet…
Obviously the title of this post gives away what happened next.. I was excited coming home with the Y-connector I needed to finally hook up the 2 outlets of the petcock on this tank with the single fuel inlet to the carbs. At last I would be able to use the bike again with all the body panels in the same colour! Well of course that’s not how it turned out. The petcock was leaking pretty much from everywhere – there was fuel seeping through from where it connects to the tank, and it didn’t matter how you turned the switch on it, fuel would still come out of the line.
This is quite a common problem with these old bikes and so petcock rebuild kits are readily available on Ebay. The irritating thing is they all seem to be from US based sellers so I’m having another look at local companies selling old Honda parts for the separate items that make up one of these rebuild kits.
If you find yourself in a similar situation to this, the first thing to do is to figure out which are the correct parts for the job. As I mentioned, I purchased this tank off Ebay so I am not sure what year bike it came from. Even if you’re looking to fix the tank currently on your bike, unless you’ve owned it from new, it is possible that in the last 30 or so years someone has changed parts that don’t match the year of your bike. It always pays to compare what you’ve got to pictures of the parts you’re about to order. Or look at some parts fiches online to see if you can find something that looks right from other years or even totally different models of bike.
My bike is a ’78, and the tank that came with it looks right for that year. It has a flap with a lock integrated into the shape of the tank on top and a twist off petrol cap underneath.
It is very obviously a different model from the spare tank I showed further up.
Not only is the petrol cap different, the petcock is as well. After a bit of research I figured out through various spare parts listings that although this shape tank with the chrome cap was used on CB550K’s from ’74 to ’76, only in ’74 did the tank have a petcock like my tank. Later models came with the older look tank but newer look petcock with only a single outlet.
Fuel system parts diagram on Consolidated Motor Spares B.V.
With the help of the above website I figured out the Honda Part Nos for the parts I need. But shipping from Holland seems a bit expensive so I might just try these people instead – John Oldfield Motorcycles in Southampton
My shopping list:
16955268020 – PACKING
16957268010 – SCREEN
16958268010 – O-RING 27X2.4
16960268010 – SPRING
16997273006 – O-RING 23X2
(Items 8, 9, 10, 11 and 14 on the diagram)



