In RI, the sticker has to be on the bike, not the plate. Most put it on one of their rear shocks so it can be seen from the back. In MA, it has to be on the plate. Check with your local LEOs.

Here is several add-on options you can make or buy...
http://www.amazon.com/Universal-Motorcycle-Inspection-Motorcycles-Application/dp/B005G50P1I
http://www.amazon.com/gp/product/B0012TLIWW/ref=pd_lpo_k2_dp_sr_2/185-6825123-1686103?p

'04' Black America