How comfy are time-trial bikes for long distances?

[samwilliams]

If you were going to spend 12 hours/day for about 8 consecutive days on a bike, a large portion of which will be on the flat, would you use a road bike with aerobars or a full-on time-trial bike?

I want to save energy where possible, but am a bit concerned that spending this much time on a time-trial bike might not be manageable.

Does anyone have any experience of this kind of thing?

[samwilliams]

Thanks for the suggestions. The roads are mostly fairly straight and quiet, so it should be possible to stay in a tuck position for quite lengthy periods.

I'm definitely leaning towards the road bike with aerobars approach, especially having seen the neck problems people in the past have faced, and they weren't even on tt bikes (although they were doing the race solo, so spent considerably longer in the saddle than I will).

That's a good point about the deep rims too. I'm going to have two bikes, so may have one set of deep rims and one not-so-deep, so I can pick the best ones depending on the conditions!

[samwilliams]

It does sound like it does need to be some kind of compromise.

If you were building a bike for this kind of thing, and aiming for somewhere in the middle of TT/road bike, would you start with a TT frame and set it up more relaxed, or start with a road bike and set it up more aggressive?

(I would ask in more specialist forums, but they slightly terrify me and generally seem to descend into arguments between two people about nothing - have you seen what happens when you ask a car-related question on here?!)