Topic: 400F frame design and new tank

[blackfour]

Greetings,

For my CB400F project I want to use a new aluminium tank that I can source from a fabricator.

The fabricator has told me they have a CB350K4 frame and can make the new tank fit that.

Question: Can anyone confirm that the CB350K4 frame is the same as the CB400F frame (or so substantially the same - particularly in regards to tank fitment - that tanks could be interchanged on these bikes without modification?

Thanks,

Paul

[blackfour]

per original question but...

Is the CB500 frame the same as the CB400F?

Thanks,

Paul

[bryanj]

500 not even close
350 dont know

[Bodi]

I have considerable doubt that the 350-4 tank is the same fit as the 400F.
They look similar in pics but the rear cushion (rubber thing that the back of the tank sits on and clips into) is #17613-333-010 for a 350-4, and #17613-377-000 for the 400F. Both are specific codes for that model (333 = 350-4, 377 = 400F) and the 350 one is used on a few other models but I haven't found any others with the 400 one.
It may just be something different in the frame mount with the tank socket identical... who knows? it does indicate something is different. I think maybe the tank length may differ, but I don't have both available for a comparison. There is a guy up the street with a 350-4 but he's not been too friendly so I can't go asking to take his tank off.

[carnivorous chicken]

500F and 400F -- nope.

The 350F and 400F are pretty similar, and it wouldn't take much to get a tank from one to fit on the other. They have different (but similar) mounting styles at the rear, but I think the 400F tank is also a little longer. The front is not a problem, but (again, IIRC) the 400F tank is slightly thinner through the tunnel, and you'd have to shave the rubber grommets where it mounts. Petcocks are also different -- 400F is screw on, 350F is bolt on.