[RunningForT3]

In a couple of weeks I'll do a TT... it's an out-and-back course with very strong winds. On the way back, I'll probably have a 20-30mph tailwind.<br><br>
In this situation... do I need to stay aero, or is it more beneficial to stay as upright as possible?

 

[LeftRightRepeat]

I'd think it rare that you'll have a consistent tailwind that's faster than you're moving. More likely you'll have gusts and lulls and constantly changing direction. Winds seldom blow steadily in one direction. But if that *is* the case, by all means, be a sail!!!!

 

[Doug33]

I have wondered about this myself. I would be curious to see some real evidence proving one way is better than the other.<br><br>
It seems to me that the less frontal area exposed would mean moving thru the air with less resistance. Wind pushing on the tail would be just an extra push. Kind of like a tractor trailer vs a corvette as far as cutting thru the wind?

 

[jroden]

I think if you have your bike setup properly you might open your hip angle up when you sit up and make less power. The larger issue is budgeting your energy right in the tailwind section and maintaining your focus in the headwin and not goofing off when you see the slow speeds.

 

[LeftRightRepeat]

Unless the wind from behind is as fast as (or faster than) you are (i.e. a 20 mph wind and you're doing 20 mph), then you are <i>still</i> moving <i>through</i> air at a reduced velocity.<br><br>
If it's a 10 mph tail wind and you're doing 20 mph, you get the same wind resistance that you would doing 10 mph in still air. It's a lot less (resistance changes proportional to the cube of velocity. So at half the speed, there's 1/8 the resistance) - but it's still resistance - and you want to minimize it by staying aero.<br><br>
Once the wind is faster than you (it's doing 30 and you're doing 20), you want it to pull you along!! Then, it makes sense to be a sail. Even if you increase speed to 25 mph from the tailwind "push", you're still traveling slower than the air and not worried about frontal area.<br><br>
Of course, if you're able to outpace the wind with the extra "push", you're now back to the first situation.<br><br>
Of course, this all ignores the biomechanics that JR alludes to. If you change your position, you may be able to make less power.

 

[RunningForT3]

I think the best thing to do will be to look at what the big boys are doing, and do the same. I'm just hoping to hit my first ever 20mph average. Over there, 20-30mph is a steady wind, gusts go up to 40-50. I rarely stay aero in training, because I'm afraid to fall.<br><br>
JR, is there less power if I'm more upright? I thought that the more aero you are, the less power you get, but it's compensated by decreased resistance. Then why do people climb on the hoods?

 

[jroden]

People climbing on the hoods are not riding a tri bike with a 78 degree seatpost and 6 inches of drop to the bars, it depends on what you are riding and at what point you have the optimal hip angle.