Topic: '73 Tank on a '77

[bunghole]

I'm putting a '73 CB750K tank on my '77 CB750K.  I noticed the '77 has a vent tube and the '73 does not.  Does it matter?  Is the cap vented on the '73s?  Will I have to use a different petcock?  They are both screw on types.

Thanks!

[Burke]

I believe that the tube on the 77' is more of an overflow instead of a vent.
The 73' cap should have a vent, if not, once running you find out in a hurry

[Jay B]

I know that on a 550 the earlier gas tank is about 1-1/2" shorter than the 77-78 style tanks, leaving a gap between the tank and seat. I'm pretty sure the 750's are the same way, but someone who has tried it will weigh in I'm sure. They both vent through the cap.

[bunghole]

Cool.  Thanks!

There is a gap, but since I'm planning on making a cafe style seat, I'll just deal with it then.