To the original poster, I have an '05 ZX6R/636... First, congratulations on your purchase. I personally think they're some of the finest bikes on the market, but I'm very biased. I could have bought anything, but I chose another Kawasaki. They may be noisy, but they're comfortable, and smooth. Very rider friendly.

This may sound silly, but have you cleaned and/or lubed your chain after those 400 miles? For me, I've noticed that makes a world of difference. It's not as noisy after taking a few minutes to clean and lube the chain, and it feels smoother all around. Also, after oil changes, it feels rejuvenated. You shouldn't have to change your oil after 400 miles, but the chain could use some attention every few hundred miles if you can. Like I said, for me, it makes a noticeable difference.

Can you try and describe what feels so rough about it? Anything in particular you can pinpoint?

Also, are you breaking the bike in correctly? I assume not since you said it's been ridden hard and you're only at 1k miles. What kind of gas are you using? 93 octane only hopefully... You really want to try and be careful when you're at the low mileage you're at as far as how you ride it. Try and take it easy next time bro. A lot of people suggest changing the oil several times when you're breaking it in. A lot of people do it at 60 miles, 500 miles, 1000 miles, 1500 miles, and then 1500-2000 miles later. That's a little excessive, but it might be worthwhile in the long run................. maybe.