Topic: cb 500 f or 500 t fuel tank on cb400 four

[Thl]

Hi
I was wondering if someone had some experience with this conversion:
I’m thinking about putting a fuel tank from a "500 four" or a 500 twin" on my 400 four from 76. Will any of the tanks fit straight on or will some fiddling be needed.

Thorsten

[Uncle Ernie]

I don't know what those other tanks look like-

I have had trouble fitting other tanks on the 400 for 2 reasons;
The frame tube rises up to meet the triple tree (most frames seem to be straight?)
The coils REALLY bulge out on the sides of the top frame tube.

Other tanks can be cushioned at the front -I ened up using a piece of tire in there to keep the tank from wearing out on the frame spine- but the coils may need to be relocated.

 ?  Does that help any?