Washers between the gas tank and the frames at the rear mount

[DANPATCH]

On the very early bikes were there washers between the tanks and the rear mount brackets at the rear of the gas tank that would space the gas tanks out

[sw48]

When I have mounted tanks on my knucklehead IMG_3943.jpg , flathead and panhead bikes the washers shown were used on the studs after they passed through the brackets on the frame so no, they did not serve as spacers.

[vph-d]

I have used flat washers to space out the tanks occasionally for years.
vph-d

[otis71]

As with many things using old sometimes distorted parts, use spacers so the tanks aren’t pulled to the mounts further distorting the tanks. I usually snug the rear mounts without spacers then space the front two as needed.

[Omarttentmaker]

As with many things using old sometimes distorted parts, use spacers so the tanks aren’t pulled to the mounts further distorting the tanks. I usually snug the rear mounts without spacers then space the front two as needed.

Here's something I found useful. Instead of spacing out the tanks by placing a washer on the stud first, I turn a piece of 3/4" cold rolled and make a washer a little thicker than 1/8", and I drill and tap that piece for 5/16-24. I then thread that piece onto the tank stud and it acts as a stop and a suipport for the tank. I'm sure we've all seen repaired studs on tanks in this spot over the years. The threaded washer transmits the load away from the stud. It also allows you to position the tank without stacking up washers. You can screw the Threaded washer on al the way, or as far as needed to space the tank away from the frame bracket.