Changing shifters... need advice

Possible, but that bike sounds like it's a big-box discount store type bike? Only the Wal-Mart type bikes have the Revo twist shifters on a drop style bar and are "21 speed"? If it is, the money you send on it is probably better off going into the new bike fund and getting something better built, fit and equipped for next season. I wouldn't put $80 in shifters, $70->$200 in aerobars and $30 in cables and untold labor charges on a $300 bike.

I have slightly different advise - get the aerobars.  You can move them to the next road bike, so unlike shifters or cables, there is no loss in your investment. Unless you plan to make the next bike (and all subsequent bikes) tri -bikes. Even if you do, you will have had a chance to get used to the aero position.

Good guess Pitt, it is your run of the mill box bike.  I am really just trying to make it work for now to get my training in.  I really hope to be able to save the money to buy a "real bike" before my first Tri.  If not then I will have to make this do for the first couple of sprints.  I guess I can leave the shifters as they are and just ride some clip on aero bars just to get the aero position training for now.  Any other suggestions?

My only other suggestion follows the same basic principle of what you can swap to a better bike. If you don't have clipless pedals, get a set.  Most better bikes don't come with pedals, so you would end up getting them anyway. The only thing that you might swap and keep on another bike is the seat, but only if you are having trouble with the current one.

I get your logic that upgrades will be carried forward. Still, I'd save up as the bigger improvment comes when you go from a 28 pound bike to an 18 pound one which is more task purposefully built.

Pedals might be a good start. Aerobars would be too. Nothing more. As for the aerobars, can you get them mounted on the handlebar tops? Or are those Revo shifters there? Isn't that handlebar actuallys plt at the shifter on those bikes? It might be a very tricky install....

It is going to be a very tricky install with the shifter the way it is... that is why I was considering changing the shifter.  But I do agree that putting a lot of money in this bike would be a waist. 

why not just buy the pedals and forget the areo bars. one less thingto get rid of if you decide not to persue triathlon. however we all here know you will continue with tris. but seriously waitf on the bars. my .02