Need 1 mph on Bike

Yeah. I know. I've been riding the course weekly.

Buy the new P4, they say it is 40 seconds faster........

LBS didn't have my size in stock!

get a pair of aerobars and make sure you are comfortable, that alone should pretty much get you there,

the weightloss sounds like you are working on the engine so keep at that side and you shoudl be golden.

I'm an avid roadie but tri newbie.  Went with Profile Deign Aerostryke due to reputation/build quality, low-cost, and flip-up pads (option to grab the bar tops for climbing on steep hills).  After a little time dialing in my position, I love 'em.  The elbow pads rattle on bumps unless you're on 'em in aero position, but that's no biggie to me.
Speed-wise I gained around 1-1.25mph on level ground cruise (21 vs 22.5mph with same effort/HR).  Might get you close to 20mph ave.

Do you have an aero helmet? Supposedly, that is the same time savings as fancy wheels, but alot cheaper! I agree with the "work on the engine" part. Are you doing intervals and tempo sets? Just riding the race course is not enough.

No aero helmet. Any suggestions for some intervals/tempo set?

I just started using an aero helmet. avg 21 on my last Oly never did better than 20.5 on a sprint. not sure if it was the helmet, banner day or just like longer distance.

not sure how much you are riding, but some key workouts you could use:

tempo work:

include in a 1:30-2 hour ride- something like 2x20 min, 30 min steady, etc at tempo pace (80-88% of threshold/hour TT pace).

threhold intervals can be slip up a number of ways, but things like:
2x20 min (these HURT)
4-8x6 min
etc are good

HARD hill repeats will help a lot.

you need to ride harder as much as you can and not have it cut into the next workout.

make the hard rides hard, and keep the easy stuff easy.

How do you define "hard" hill repeats?  Out of the saddle climbing?  Spin like a mad man?  

Did an interval workout today. I used the built program in my Garmin Edge 305. It's based on heart rate. Seemed pretty, good. Not just out "grinding" the miles.