No, you won't. But depending on the size of the riser, it may look kinda funky. But it's a comfort thing so who cares. Plus, funky is good!
Here's a link to the 6 1/2" Yamaha Tall Billet Handlebar Risers. These will move the bar back significantly, but they're very pricey. I'm sure if you look, you can find something similar at half the price.
http://www.starmotorcycles.com/star/products/modelscitemdetail/5/60/119/852/2007/1/887/0/0/detail.aspx