Many, many have mounted hardbags and luggage. Most have chosen to do something ready-made, a few have done their own.
One of the ready-made solutions is something like a Vetter system. Everything is made for the bike and it bolts right on. Might not be the most aesthetically pleasing, but it works.
I chose to go with a ready-made system that had to be modified a bit. I have saddlebags and trunk from an 1100GK. I had to make an adapter plate at the rear of the frame to hang the lower framework, and I had a welder friend put a support on the footpeg mount to be able to fasten the brace that normally mounts to the 1100's footpeg bracket. If you didn't know that Suzuki never offered that luggage package on an 850, you would never suspect it. You can see the results by clicking on the link in my sig.
For my wife's bike, it came to us with some throw-over leather bags that I fastened under the seat. I also made some brackets that kept them from going inward to hit the wheel or down onto the pipes. Last year, my sister decided she wanted to upgrade the bags on her bike, so we got her old ones. Had my welder friend make some mounts for them and I am very pleased with the results. You can click on the link in my sig for my wife's bike to see the original leather bags, but here is what is on the bike now:
Bare bike:
Completed bracket. It's a little hard to see, but the top-front corner has a couple of angles that take it back to the shock mount.
The top-rear is bolted to the luggage rack, which is securely mounted to the frame where the turn signals used to be. (they are moved to the license plate area)
The lower-front has a brace that reaches forward and down to the inside of the footpeg/muffler mount.
Bag mounted:
Completed project:
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