Whenever I stand up on the pedals climbing hills it feels like my brakes are rubbing on my rotors. I weigh 205lbs and when I climb I move the handlebars left to right to get more power with my bar ends. Am I causing the brake discs to go off center? My bike feels really sluggish on the flats afterwards too. Are the wheels shifting in the drops?

Lars

First,make sure your wheels are mounted properly. This prolly isn't the issue,but it always helps to eliminate the simple things first. Next,what kind of discs,hydro or cable? If they're cables,it sounds like the pads might be adjusted a bit close. Just back them off a touch and you should be alright. If hydros,it could be either the calipers aren't centered properly,or they're just not high end. It's not uncommon for low to mid grade hydros to drag a touch;my old BBU used to do it sometimes after a hard stop and it would quit after I hit a good bump. If they're hydros,have the shop take a look at them to make sure they're centered properly and that nothing has gunked up the seals to prevent the pads from fully retracting.

sounds like you're torquing the whole frame. try and run a lower gear and pedal faster and smoother so you're not putting huge sideways loads on your wheels, the bike will last much longer. if you hammer on it like that you will blow out the bike, and eventually blow out your knees.

When climbing I'm in the second lowest gear. First gear I wouldn't be able to pedal unless sitting down. I have hydraulic Tektro brakes. I took it into the LBS and he said everything was just fine and he took it for a spin as well. So I guess it's just me. I thought I was in good shape on my last 50 mile trip around the hills in Seattle. It's funny though, when I told him I get delays in shifting on one gear occasionally, he had the bike on the repair stand and went thru all of them and nothing happened. Kind of like when you take your car in for repair of something and the mechanic can't repeat what you experienced. One salesman also told me not to expect my hybrid to keep pace with road bikes. I said that was sure evident. The only time I passed a road bike was when the rider was texting on her phone while riding.

Lars

if you are torquing the frame left and right as you ride standing up, you are wasting a lot of energy. sit down, pedal smoother at a faster cadence (RPM) and you'll go faster/farther

Which gear? Front or rear shifting? If it's in the lower end out back,it could just be the transition to the larger cogs in the cassette;the gearing is spaced wider in the low gears and tighter in the high ones. If it's up front it could be the chain line;if you're trying to go into the big ring from the lower gears,it'll sometimes hesitate do to the big jump in teeth and the angle of the chain. It's also not unusual for a bike to shift a little differently under load than when just hanging on the stand.