I did the fly screen extension mod today to my Roadster.
This gives you some extra space to put stuff and still get to the key.
It is not riding weather yet so i haven't tested it at high speeds but it feels solid and stable.
I only did a 1" spacer but 2" probably would have been better and still looked & functioned fine. I would also go with a larger diameter spacer for more stability for that length.
3" starts to push it out in front of the headlights and I'm sure more air would get in underneath.
If you want to do this mod at 1" here are the part numbers and cost for TWO Rockets from
boltdepot.com :
Product# Description Quantity Unit Price Subtotal
13684 Spacers, Chrome plated steel, 1/4" x 1" (1/2" O.D.) 1 bag of 10 $19.05 $19.05
6694 Metric socket flat head, Stainless steel 18-8 (A-2), 6mm x 1.0mm x 50mm 8 pcs $0.47 $3.76
15947 Metric flat washers, Nylon 6/6, 6mm 8 pcs $0.08 $0.64
(white - no black ones were available here)
Summary
Subtotal: $23.45
Shipping: $4.95
Tax: $2.28
Total:
$30.68 = $15.34 per bike (a little less if you went with non-chrome spacers)