Tour de France time trial question

[Salad Dodger]

Forgive me for asking a real dumb question, but I am a mountain biker, not used to the subtleties of road racing.

I was watching the time trial from TdF this afternoon, and several of the riders had saddles with what looked like a big plastic ring sticking out at the back, where I would have a little saddlebag attached to my dirt bike. What is the purpose of that, please? And surely, if they are so fanatical about saving grams of weight with carbon components etc, couldnt they have cut this (apparently) redundant fitting off the saddle to save a few grams?

I should be grateful if someone could put me right about this. Thanks.

 

[Steve H]

Yes I saw these. Would love to know what they are for

 

[Crackle]

I thought I saw someone with a bottle in one.

 

[Chuffy]

Didn't see one, but some TT saddles have a bottle cage fitted at the back of the saddle as it's more aero than a regular cage on the frame. Not they would need a bottle on such a short course.

As for weight, it's not such an issue on TT bikes. Being aero and stiff matters more than being incredibly light.

 

[Salad Dodger]

Thank you for comments. I had wondered if it would be a bottle holder, but not knowing much about road bikes I thought there might be some technical, aerodynamic purpose....