OOWWW my shoulder!!

under your shoulder blade? (not sure I understand where you are talking about) sounds like tightness in your lower back. Is the pain immediate or does it come on after a while in aero?

well not quite under but up and to the inside of my shoulder blade

I need a bit more info to really make an educated guess.

1.) Tri bike or Road bike w/ clip ons
2.) Were you fitted to it?
3.) How long have you been riding?
4.) Fitness history?
5.) Is the pain immediate or does it come on after x amount of time?
6.) Do you do any pre / post stretching / foam rolling?

1.) Tri bike or Road bike w/ clip ons              Tri Bike
2.) Were you fitted to it?                               Yes
3.) How long have you been riding?              2 months
4.) Fitness history?                                        runner all my life
5.) Is the pain immediate or does it come on after x amount of time?      after about 10 min in the aero position
6.) Do you do any pre / post stretching / foam rolling?                             post streching...what is foam rolling?

foam rolling:
http://www.tmuscle.com/free_online_article/sports_body_training_performance_repair/feel_better_for_10_bucks


I would say it is one of two things.

1.) Cockpit/aerobars are not quite dialed in. Maybe the aerobars are too tight, or possibly you are stretched/cramped.

2.) Add some deadlifts to your workout routine. It's common to only "lift weights for muscles you see in the mirror."  A lot of times people get squats in, but leave the back end to the mercy of the hamstring curl machine. Strengthening the lower back/hip flexors/quads will make getting into and staying in aero easier.

I would look at those two things first as I think one (or maybe both) will fix it.

Good luck

Thanks so much!! Sounds like a plan

It may not be a problem with your fit at all... just time getting used to the position. As you build volume if it doesn't improve I'd look at the fit again. It's not a natural position, so there's some discomfort to be expected as you're getting used to it.