I don't know if this is normal or not, but I've been hearing a grinding noise from the crank area on my alpine 450. I started as soon as I got the bike. I had to replace the right side crank when I first got it becuase the crank was bent when it was shipped. Did I not tighten it enough? What do you think it might be?

Most likely culprit being a faulty bottom bracket. I would recommend posting this dilemma in the "Everything Drivetrain" board. You'll probably get better response there. Be sure to list the brand and model number of the crankset and bottom bracket in the post, as some crank/bb sets have a history of specific problems. This info will help people who might be able to respond with possible resolutions.

Bob