None what so ever.
The bike is awesome. I saw a lot of people talking about the comfort. I am a bigger guy, but not that tall, only 5'8", but I am very comfortable on the bike. The bars are almost perfect for my stature. I wish the controls were a little more forward, like the ones on my buddy's Shadow.
I am very impressed with the power of the bike. I raced my buddy's shadow, and he couldn't keep up. The bike was very stable at high speeds. I pegged the speedo at 120, and it felt like it had more.
Very nice cruising at highway speeds, between 70-80 mph, but I absolutely hate the location of the ignition - if you have any type of key ring on it, it will wear off the paint on the plastic side cover. And it definitely needs to be louder!
You hit the nail on the head with the key ring and the pipes being very "tame". Other than those things, and the controls not being forward enough, I love my '06.
I had an 06 M50 with Vance and Hines "Cruzer" Pipes on it and the sound was fantastic. It was louder with the baffles in, than my buddies C50 stock pipes with the baffles removed. I think that the M50 is great.
I come come from a sport bike background. The only thing that I would improve would be better braking. At high speeds I feel like I'm landing a fully loaded 747.
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