I commute on my drz, and 6 months of the year my evening commute is in the dark. I installed a more powerful bulb and pointed the light a little bit further up than the way it came. It works wonders. It's only $8 and can be done by a monkey in 10 minutes. I would highly recommend you give it a try before spending more money.

http://www.amazon.com/gp/product/B000COBLKW/ref=wms_ohs_product?ie=UTF8&psc=1