Ok I am training for IMLOu and I get awesome speed going down the hills but when I hit the hills I shift to the smallest gear and spin up but I lose so much momentum and go up slowly. When going up the hill from a down hill do you shift one gear lower and lower as the % grade get steeper to keep momentum and if so how do you keep yourself from NOT using too much energy and keep doing it over and over the next few hills coming up. I hope I made sense.
Sometimes it’s good to anticipate the hill, and shift several gears easier if you are coming into the uphill with lots of speed. Most of the time, just shift one/two/three gears at a time as the grade goes up. You’ll find the more you ride hills, the better you’ll get at matching the gear to the effort required.
Face Palm
So, you cant shift your bike but you are ready for Ironman?
Don’t be an asshole, dude. Why do you need that? Explain that to me please? What gives with you?
I hope you’re not using a TT bike. I believe you need time on a road bike before moving to a TT bike.
Your question tells me you just need more time on your bike to get a feel for shifting.
Have a good race!
Gradually shift as the loads on the pedals get more and the cadence gets less.
Ease up on power for just a tiny fraction when you shift under load.
If the drivetrain still makes a GIANT THUNK when you shift even when easing off power, well congratulations you’ve chosen SRAM and that’s perfectly normal behavior. 
Yup. Never ready for an ironman but I am trying.
Okay - this person can not shift his bike - not with out loosing all of his momentum (as he/she clearly states). That tells me that this person is not adept at riding their bike. As pointed out in the OP’s question. Proper training would have easily been “proof in the pudding” if you will for proper riding safety. If a rider suddenly is coming to a halt up a hill…you want to be the guy behind them coming up into the zone fast?
So, if this poster who states that they do not know how to properly shift their bike - who is going to a course that they are not confident that they can ride in a safe manner - I dont get it. Rather on the bike than on the swim of course - but would YOU enter a race when you do not know how to properly shift your bike?
Proper shifting is EASY, and a skill that is quickly learned. No one needs to know gear inches and on and on - but I imagine that the reason the OP has issues is that he or she is climbing on bullhorns and not aero - I get that - cool. But, the OP (again, me presuming) can not ride no handed (as most Tri bikes dont do that easily for novice riders) - So, when shifting the OP takes one hand, grabs a shift lever and thus spins out - not able to go down the front, and down the rear in a single swing - momentum gone in a flash. However, if I am correct, the OP needs to already be in their small ring BEFORE they get to an incline - and go gear to gear from there. Dropping from big - never fun unless you can do down in the rear as well. (Again, a skill that should be aparent before someone enters an Iron distance race.)
You have bar end shifters or STI?
Here’s an article on the bike course along with a description of the swim and run:
http://www.active.com/triathlon/Articles/11-Keys-to-a-Successful-Ford-Ironman-Louisville.htm?page=2
The bike course doesn’t appear to be too difficult. You have plenty of time to train for your IM and get comfortable on the bike.
You can do it. Don’t listen to Record10Carbon.
He already said he cant shift.…pretty clear evidence to me 
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loosing all of his momentum
it’s lose bro. loosing aint no word american word brodi.
You do not want to shift too soon because you will lose lots of speed and power. I watch my cadence. I want to be right around 85-90 on a hill. If the hill starts to get steeper, my cadence will drop below 80 and that when I know to shift to an easier gear. Sometimes you get to an easier portion of the hill and cadence goes to like 95, thats when I know to shift to a harder gear and bring it back to 85-90. Pretty simple concept. As your legs get stronger, you can keep a higher cadence at a harder gear.
Tel mah speel cheque - and get over it. I hope you fel betta fuer pointing that out. Occams Razer, yew ant gots a point soyas finds eh speeling arror.
Pathetic. I hope you have met your goal for the day…
Now, onto shifting.
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He has about 30 days to get comfortable shifting. I just hope he’s not using a TT bike. That would be silly!
Competing in a tri is not that difficult. He can do it!
He has about 30 days to get comfortable shifting. I just hope he’s not using a TT bike. That would be silly!
That you are right about. The time lost trying to get proper shifts on a TT bike, weaving and the fact that he is not comfortable tells me that there would be a huge time savings on a Road bike - if my theory is indeed correct that it is reaching the levers that is at issue. Throw on some clip ons and you are set - split shifting even on 105 is easily handled with the two handed operation. If that is not an option, the OP needs to potentially twist his shift lever in so that one handed he can grasp both levers with out the bike veering hard to one side or the other (as often happens when reaching out for a bar end one handed). Hell, just in the past week there have been how many posts about blocking on the bike courses? (Door, LP and others) - I am sure the OP would feel terrible if he made an inadvertent swerve and got hit from behind or the side by another participant.
My guess - like most newbie tri folks, their first and only bike is a full on Tri rig that they were never taught how to properly shift (being as they dont ride in groups).
Agreed. This is very helpful.
Don’t be an asshole, dude. Why do you need that? Explain that to me please? What gives with you?
I think his boyfriend stopped giving him reach-arounds. Not that there’s anything wrong with that.
There are alot of Assumptions begin** **made here and alot of great advice. I have NO problem shifting between grears and I never weave when going for my gears or have handeling issues. The ST`er who provided some great advice thank you. You made me realize timing and cadence is key and I will pay closer attention to that.