It does get crowded no doubt. If you go to Main Street, the main attraction, with bikes lined as far as the eyes can see, in the early evening, when everyone wants to hang in town, both main streets, Junction Ave., and Lazelle St. are just a total mess. You could be there for 45 minutes, in stop and go traffic. I stay away from that time of the day, same as with lunch time. Most locals just get out of town for those two weeks (the rally is in full swing the week/weekend leading to the official rally dates), and rent out their homes, and front yards to campers. So, there are cars and trucks on the I-90, but mostly it's just bikes everywhere.
I-90 can handle all those bikes quite well, and everyone is able to travel at the posted speed limit of 60 mph anywhere from Spearfish to Rapid City. The entire region is busy with bikes everywhere, regardless of where you go, that it be Sturgis, Deadwood, Lead, Central City, or Keystone, but not so much Rapid City. My take on that is that the cars (though still present) have been replaced with bikes, and I don't mind that. Most riders know how to behave around other riders, and understand what we know about riding a two wheeler. I have found most of them to be respectful. Going to Deadwood from Sturgis is always a pain, and that road will get backed up, at certain times of the day, especially mid morning. Sturgis is the only place in the world, and call me crazy if you want, where I leave my leather jacket, my helmet, and anything else on my bike so I can walk free of stuff, and not worry about it. Other bikers are always there, and we all know better than touching someone else's bike, and steal from another biker. One year, after spending the entire afternoon in town, and while returning to my bike, I reached into my pocket to retrieve my motorcycle key, and it wasn't there. I thought I had lost it (I had the spare at camp), but upon getting back to my bike, I saw that I had simply left it on the bike! It had been there for hours, and I'm sure plenty of people noticed it, but no one stole my bike. I wouldn't try that in Denver, even in the safest neighborhoods. At times it does get to be too much, and it can be frustrating, in the 90º weather, but I love that for a week I get to live in a world where everyone rides a motorcycle around, instead of driving a car. Utopia is bliss, I guess. I stay at a campground that is family oriented, unlike many other camps (namely the Buffalo Chip) that are just big biker party camps. For $30 a night, I get a spot for my tent in the shade of the trees, a shower, a clean bathroom, a pool, a bike cleaning station, a washer & drier, a café that serves Breakfast, and dinner, as well as a bus shuttle to town, if I'm ever too tired to ride to town. There is also a bar with live music. I love sitting in/at the pool all afternoon, and watch all the bikes rolling back to camp, after whatever fun day they had for the day. Everyone at the pool is talking bikes, and the rides/roads around the hills. Pretty awesome biker dream. I realize this is definitely not everyone's cup of tea, but I'm really enjoying reading the pro's and con's in this thread, and other places people like too. Thanks for being straight up, and up front. I like that.
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From all the folks being there it is certainly a blast for many folks. Good for them!
