I bought a used 2009 Enertia Classic in Sept 2014 and have made some mods that make it a much more useful commuter: 1. O-ring chain 2. Windshield 3. Tail Tidy and Luggage Rack with LED lights. The last is the best since it increases safety and practicality. I'm not a 100% done since I plan to paint the aluminum rack black and improve the fit and finish to look like OEM. The overall look is close enough to a stock and I like it. Now I can strap my Tumi briefcase behind the seat securely and not obscure my tail light. Also I have a place to drape soft side panniers if needed
Other options: Sling briefcase on shoulder is unsafe. Givi side cases are expensive ~$500 kit, still too small and changes the sleek look of bike. Soft side cases from Brammo are way too small.
Here is how I did it:
1. Cut off the Stop light assembly from the Tail plastic assembly - cut just to the rear of the hole closest to the seat. You can use a simple hacksaw or knife to do this.
2. Remounted the tail light assembly and the turn signals just above the the license plate light -- the turn signal light bolt (red) is used as fastener; A second hole is needed for turn signal cables to pass; a third hold for a small M4 bolt (blue) to prevent the tail light from rotating; some plastic trimming needed; Closed off the holes in back of tail light for wires with tape to prevent rain going in.
3. The metal brackets attached to body has an upward facing kidney-shape flange to cover back of seat - this was cut off. No other changes or drilling are needed on the metal bracket of body.
4. I then proceeded to create a 2-tier storage area in the space cleared by the tail light. A thinner piece of aluminum was shaped exactly to match the plastic' tail racks contour and forms the lower rack (blue line under tail light). A thicker aluminum plate with 2 simple bends provides a platform for my briefcase. Both are anchored to the tail metal bracket (no extension) using original holes and M6 bolts (green).
5. I also bought Brammo soft side case racks (the supports only) for left and right ($55 a piece) and mounted with M10-30 bolts into the bike's frame bolt holes. These will provide strong anchors (orange) for 2 ROK straps attached to them, but also allow soft luggage draped over the luggage platform.
6. Look - A place for my briefcase with ROK strap attachment; Since it is so close to the frame it does not create a cantilever effect and is easily strong enough. And a bonus area accessed from the back under the tail light -- to store your toolkit, puncture kit and extension cord etc.
7. Finally to wire this all back up you need to extend the tail light wires, but rest are long enough (remember we never lengthened the tail). At this time I also added a http://www.run-n-lites.com/prod-LiteBlazer.html
to provide extra visibility.
Total cost was Brammo Side pannier racks (part# 95187532 RHS and 84955531 LHS) $110 + LED Lite Blazer $75 + Aluminum and fasteners $20 +ROk straps $13; Warning!
While body and metal rack is unmodified and aluminum platform is close to the frame and strong, a briefcase or bag is all I would put there. DO NOT OVERLOAD OR USE AS SEAT.
Hope this helps.