Why do my knees hurt while on an exercise bike?

if I ride on one of thise exercise bikes would I loss weight and tone up my legs

okay well my knee hurts really bad is there anyway I can pop it? or something?

Does exercising on an exercise bike burn fat all over (like on arms?) or just the leg area?

how can I jump higher without hurting my knees long term ? and training anyone knows ?

I hurt my left knee but not to badly,is there anyway I can rehab it before school shopping starts next weekend?

To day I was riding my bike for a long time to get my thighs tither and more musle right so when I got off I had pbj and milk...

Hey im only 13 but my knees crack worse than my grandmas! Im a runner, so that puts extra pressure on them. They hurt really ...

I was on seventeen websight right and I was exercising I could feel it on my thighs today it kind of hurts is it a good or ba...

I have really weak knees, and when I do squats or lunges they hurt. So what are other butt exercises?

I have herniated discs in my neck and nerve damage down my arms. How can I reduce the size of my upper arms and also my stom...