You are off to a great start. I am of the opinion that diet takes the pounds off but biking will help you keep them off. I started about 390 plus on a seven speed cruiser. I had to work up to the three mile ride to my work. Now, three years later, I'm at 260 and ride 26 plus miles twice a week (new job). I was at 240 but we all have weak moments. I put the cruiser in storage and now ride a hybrid with 37 mm. tires. At 350, you should not have to worry about wheels if they are adjusted to began with. That is my opinion but I could be wrong.