+1 on the cadence sensor and just generally working on your cadence if you're bouncing. Chances are it's just a matter of learning to get smoother, and the only way to do that is by working on it - spinning up to higher and higher cadences trying not to bounce, and maintaining it longer. If seat height has anything to do with it, it's probably your seat is too low - then your legs are trying to extend too far and pushing your butt off the seat. (When the saddle's too high, your hips tend to rock side to side, because your feet are pulling your hips down off the saddle at the bottom of the pedal stroke.)

Quote Originally Posted by FlyingScot View Post
I was told to never ride the flats on the third chain ring, which was suggested in one of the threads, because it was hard on the bike..any thoughts?
Not sure who told you that (maybe your know it all brother ?). You should ride in whatever gear gives you a smooth and comfortable cadence. If you're a fast rider, have a tailwind, or ride in pacelines, you may be in the big ring on the flats quite a bit! What you shouldn't do is cross-chain, i.e., ride in the big chainring and the biggest freewheel cogs, or the small chainring and the smallest cogs. It should be obvious to you when you've accidentally shifted into one of these gears, because your chain and derailleur will make noise. In these positions the chain gets a lot of lateral force, which it isn't really built for; and also the rear derailleur will be at the extremes of its ability to take up chain slack, and the front derailleur may rub. There is plenty of overlap in the gears, so that instead of cross-chaining, you can shift to the middle ring and get a very similar gear ratio.