I recently purchased a used Enertia Classic. I needed 2 mods to make it a better commuter - - a luggage rack and a windshield / windscreen / fairing. I'll write about the Windshield mod here. Please look
http://brammoforum.com/index.php?topic=2821.0 for the tail tidy and luggage rack post.
Windshield for Enertia Classic -- As folks know there is a Brammo small windshield part for the Enertia Plus but it mounts to the headlight bracket and won't fit the Classic. Then I pursued the National Cycle Deflector DX suggested above, but the company told it won't fit either since the support clamp bars will interfere with the LCD display. I am glad to report that I found a generic windshield on Craigslist and was able to make it work with no changes to the bike. See picture and instructions below.
1. Model of Windshield is Cyclear made in Collierville, TN. There are 2 markings on the windshield as follows. Embossed in plastic: Cyclear DOT309 - M321AS6; There is also a sticker with the company name and address and Serial # M137205. It seems to have come off a Harley but the shape and size is perfect for the Enertia, the only drawback being a curl near the headlight
2. My windshield came with 2 handlebar brackets and 2 brackets that would mount to a fork and all using SAE bolts. To attach to the bike, I used the handlebar brackets with no modification. However for the lower brackets, I had to remove the fork ring clamp that came with the windshield and use only the collar that pinches the windshield connecting rod and use a M6 metric bolt to attach the collar to the fork cross bars (see picture). In this position the rod clamps had to be reversed outside-in to allow the connecting rod to attach to the outside of the windshield (see pics)
Then with a person seated on the bike and leveled, you just have to move around the clamps and find the right fit. I chose to pull out the windshield about 1/4" in front of the headlamp to ensure there would'nt be accidental bumping or chafing of screen with headlamp or LCD dash. My ride is now quieter, more comfortable and warmer.