I'm no Sturgis expert but have been twice (2010 & 2013) on my Roadglide. Though Harley is primary sponsor, all kinds of rides (including cars/trucks). Generally it seems no one cares what you ride. Most are just there for the event and local riding. I'm going in 2015 as well - this time on my 2014 Spyder RT Limited - planning to ride there and back pulling the RT-622 trailer. For the guys I ride with (all Harley's) I'm now the official "Beverage Mule". They get why I changed to 3 wheels and think the Spyder is cool. If you haven't been to Sturgis before, Rapid City Harley has become the better venue for vendors - easy parking, lot to see and buy, bands, food, drinks, etc..
Where you stay could make a difference, we've always rented houses, never stayed at The Chip.