Soft bags can be had for very reasonable prices, but, the attachment straps are questionably secure and the paint abrasion/scratching from the bags moving with the bumps and wind is totally unacceptable.  This left me with just one other option — spend some time build my own pannier racks to hold soft bags.

I found some waterproof Ortlieb saddle bags rated at 47L. It has a “drybag” style  roll top, and semi rigid plastic shell on 4 sides. The fabric is heavy rubberized material — definitely waterproof.

First a shot of the finished product.

The frame is constructed from 1/8″ aluminum stock.  Each side bolts using 2 bolts: the bolt in the side of the factory luggage rack to support the factory panniers and one bolt that holds a bracket around the lower luggage rack support.

Here’s the upper bolt attachment. Note that the bolt goes through from the inside the bag, through the internal support frame and into the luggage rack. The three small bolts attach the square stiffener tube a piece of flat stock that makes up the internal framework (not removed when the bags are removed).

The primary part of the lower attachment is 2 pieces of 1.5″ angle stock bolted together to make an upside-down “U” shaped piece. One face of the “U” bolts to the inside of the pannier, and the other side of the “U” is used to attach to the lower luggage rack.  The “U” is wider at the front and narrow at the back in order to define the angle that keeps the bag from rubbing on the plastic under the saddle and to keep it from rubbing on the upper luggage rack at the rear. Not that this angle means the total width of the panniers is widest at the front, and narrower at the rear — which is fine with me as it keeps the weight hugged in as close to the center of the bike as possible. (please overlook my chicken strips )

The lower luggage rack attachment was the most challenging part of the design and I ended up throwing out the prototype and doing a second design here. The square tube is pop riveted to the inner face of the inner “U” shape and it supports the weight of the bags by resting on the top of the factory luggage frame.  Note that the pop rivets only hold things together when it’s detached — the attachment bolt is the primary fastener for strength.  Then, another piece angle stock is bolted to the inside of the square tube to capture the factory luggage frame on all sides.

And another angle of the lower luggage frame attachment point:

A wider shot of the lower attachment point. Note that the bit of angle stock hanging down is a heat shield to keep the heat of the muffler off the bag.

And, here’s another shot giving a good reference to the clearances to the luggage rack and the side plastic under the saddle.

Not shown is the fact that the upper & lower exterior frames are connected by means of a piece of flat stock on the inside of the bag connecting to 2 vertical pieces of angle stock at the front and back corners of the bag (all on the inside). This adds total rigidity to the system. There are no other straps/velcro needed to hold the bags on the bike — only the 2 bolts mentioned above.

So far, I’ve had them overloaded for an 1100 mile trip there’s been no issues.

Update

Since I’ve gotten a request for more info, here’s the cut-list of each part. All dimensions are in inches:

The following pictures detail what the pannier frame looks like without the Ortlieb bag. All pictures below are taken of the right-side frame.

As if it’s not obvious, the numbered parts correspond to the part number in the cut-list above.

NIKON D70, ISO 800, ƒ/2.8, 1/25sec, 38mm focal L.

If you want the top of the bag to be tucked in a little tighter, you might wish to change the part #5, Upper Stiffener to use angle stock instead of the square tubing. This would tuck the top of the frame about 3/4″ closer toward the center of the bike.

NIKON D70, ISO 800, ƒ/2.8, 1/50sec, 29mm focal L.

Below is a detail of the lower luggage rest. Ideally, if it is constructed correctly, this square tube bears the majority of weight of the bag by resting on top of the bike’s luggage frame. Thus, the top pin/bolt is not under significant sheering moment and should mostly be in tension. Achieving this goal requires carefully locating the bolt hole for the top bolt threaded into the bike’s luggage rack.

NIKON D70, ISO 800, ƒ/2.8, 1/40sec, 29mm focal L.

Below is the detail of the luggage frame retainer. This captures the bikes luggage frame on all 4 sides, giving a solid lower mounting point. The slot in the retainer piece is milled out to make room for the “tab” welded to the inside of the luggage frame. The tab is perfect to keep the lower mount from sliding fore/aft on the frame.

I cut the slot by drilling many holes along the path, and then using a dremel tool and file to clean it up. Those with access to a milling machine will make fast work of the slot.

NIKON D70, ISO 800, ƒ/2.8, 1/30sec, 29mm focal L.

The photo below is the bottom view of the right-hand side frame and is attempting to illustrate how the angled attach truss is built. This angled piece defines how much “toe” the panniers will have relative to the center-line of the bike. If you note in the first 2 pictures of this post, the front of the panniers are wider than the back (overall, measuring outside of left pannier to outside or right pannier). I chose not to make them parallel to the center-line of the bike in order to keep the mass as close as possible to the center-line. If it bothers you that they are “out of square”, adjust accordingly.

NIKON D70, ISO 800, ƒ/2.8, 1/80sec, 29mm focal L.

And, here’s another angle showing, well, the angle! This is viewed from the back of the right-hand side frame.

Also note, at the bottom of the photo you can see how the luggage “pin” rests on the square tube. Again, if you want the top of the pannier tucked in tighter, either use something beside the stock luggage peg, or use an angle stock instead of the square tube as the upper stiffener.

NIKON D70, ISO 800, ƒ/2.8, 1/15sec, 29mm focal L.

Other construction notes:

All parts were hand-fitted and positioned on the bike, marked, and then drilled and fastened. I used pop rivets extensively to quickly assemble and test fit. In most cases, when I was happy with the fit, I drilled additional (larger) holes and augmented with 1/4″ bolts for strength. The only joint that relies solely on pop rivets is the upper horizontal support attaching to the 2 vertical supports.

The astute observer might notice that the interior horizontal support (#8) is not 1.5 inch flat-stock in the photos — and you’d be correct. I used 1″ stock, but, it would be preferred to use something beefier.

One could easily adapt the concept to make a frame for other panniers besides the Ortlieb.

It was a fun project needing nothing more than a drill, hack saw (I used a sawsall), a file and some patience. All totaled up I have less than $200 in the bags and materials.

My goals for the install:

1. No drilling/modification of the luggage rack
2. Offer some amount of cushion/padding to prevent the hard case from marring the paint.
3. Position the bolts at the outside of the mounting plate to provide the most secure attachment
4. As far forward position possible, given the above considerations.

Additional supplies that I used:

• Qty 4 — 1/4″ bolts by 1.75″ long
• Qty 1 — 1/4″ bolt by 2″ long
• Qty 5 — 1/4″ elastic stop nuts
• Qty 1 — large outer diameter washer
• Heat shrink tube
• Ribbed rubber mat

The mounting points will be 2 “U” shape bolts to wrap around the forward part of the luggage rack, and 1 through bolt at the back.

Since I was unable to find a U bolt with the right geometry at my hardware store, I modified the supplied brackets by drilling 2 holes to form the legs of the U with some regular bolts.

Here’s the bracket punched and ready to drill

The 3 brackets drilled and ready to apply the heat-shrink tubing.

With the heat-shrink and the holes punched through the tubing. I don’t know if the shrink tube will survive, but, it’s gotta be somewhat better than bare metal against the rack.

Next, I outlined the shape of the universal mounting adapter onto the rubber mat to cut.

The rubber mat cut to shape. I plan to but the ribbed side down against the luggage rack.

The supplied hardware kit only had 4 square “washers”, so, I fabricated one by squaring up a round washer with a file.

Now its ready for install. You’ve all seen the bare luggage rack on the F800ST:

Put the mat down and poke the bolts through the holes punched in it. The four 1.75″ bolts up front, and the 2″ bolt in the back.

Mounting plate down, and the square “washers”, and then the elastic stop nuts.  I chose not to use washers since the bolts were just that much too short. Tight with minimal torque to avoid ripping the washers through the plastic adapter plate.

Underside shot showing how the brackets are arranged. Rear on the left side of frame, and front-right on the right side of frame.

The finished mount!

I like the narrow look of the E370 top-case. Doesn’t look so much like a flying saucer