This is how I mounted my Pelican cases to my 1990 Yamaha XT600.
I started by bending some brackets to attach to the bike out of 1/8" by 1 1/2" steel. For attachment points, I used the bottom bolt of the rear passenger holds, and the bolt for the turn signals.
Here's the left side:

Right side:

View from the rear:

To attach the Pelicans to the brackets on the bike, I welded up some square frames out of 16 ga. 3/4" square tubing. I had spent quite a bit of time w/ the plastic welder closing up all the holes the cases came w/, so I didn't really want to add any more to the cases to attach them. In studying the cases, I noticed that the bottoms had 2 ridges, about an inch apart, and there were already holes drilled through these ribs. I welded on some 'fingers' to the square tube frame so that each 'finger' that stuck out fit into the groove nicely.

I then used a drill to drill through the 3/4" tubing in the same spots the existing holes in the ridges were. Here you can see a piece of allthread I used to run through both sets of holes to temporarily hold the case on.

Another shot:

Closeup of holes:

Then I positioned the 3/4" tubing brackets on the 1/8" flat brackets on the bike and tacked them together:

Another shot of the square frame tacked to the bike mount:

Temporarily mounted on the bike:

Left side, w/ case mounted temporarily:

Right side, w/ case mounted temporarily:

From the rear view, before the cross brace to tie the two together:

To secure the top of the box from moving in/out, I welded on another 'finger', this time pointing

straight up. There were holes in the handle that I ran a long bolt to from the upright 'finger'.
Here's the mounts all finished welding, you can see the piece that sticks up:

Here you can see the upright, and the bolts I used to snug the cases to the frame:

And here's a shot of the cases all mounted up and loaded up on my way to SLAP. You can see the cross bar that I used to tie the two sides together. This is the 2nd version.

The first version went straight across about level with the bottom of the license plate, between the tire and fender. A rough railroad crossing at 45mph was enough to bottom the suspension enough to stuff the tire into the crosspiece. Luckily, all it did was bend it inward and up, could have been much worse. So, the new version is mounted further down, and bends out to completely clear the rear tire at full suspension compression.

Since I wanted to be able to quickly remove the cases, my original allthread mount wasn't going to work too well. I ended up picking up some locking wire pins:


They're great b/c there's nothing to vibrate off on rough roads, and no pin to drop & loose on the side of the road. Plus these allow me to unclip the boxes pretty quickly if I want to take them off. For the upper bolts that go through the handles, I drilled through the bolt and used a butterfly nut drilled for safety wire, with a paperclip twisted through them to prevent them from backing off due to vibrations.
I also picked up a 4 pack of identically keyed small padlocks from Wally world to secure both cases shut. So far it's worked really well.


Thanks for looking,

--JOsh