Hypno Toad

I got my first carbon fiber bike this year, 2021 Bianchi Infinito.

The seat clamp slipped, cutting my ride short on Tuesday, I finished my ride at the LBS to have them help me with a torque wrench. Today the seat clamp slipped again .... WTF?!?

This week has been my first rides in cold temps with this bike, 13°F today. But that shouldn't effect the seat clamp, should it?!?

I'll contact the shop where I bought the bike this weekend. Just interested to know if this is a common issue, or just a personal issue.

masi61

You say the seat clamp slipped? Or was it the seat post that slipped? Not sure if the Bianchi Infinito uses a round post or some special cross section (such as a D shape) post. Definitely contact the shop again to let them know it is still slipping. This is one of those types of things that you just have to keep looking at until you resolve the problem. They can put carbon fiber grip past on the post and also torque the seat collar up to the torque spec. Different seat collars have different torque specs. Some factory seatposts are not of the highest quality and may be slightly undersized.

Could you post a photo of the seat collar and the seatpost?

Airfehr

Get some carbon grip from your local bike shop.
https://www.rei.com/product/801108/f...-gel-175-fl-oz

Hypno Toad

It's an integrated seat clamp that isn't holding, letting the seat post slip down. It's a D-shaped seat post.

Here's the integrated seat clamp



And the strider set up

Hypno Toad

Thanks! As a n00b with carbon fiber, I didn't know this was a thing.

masi61

Hypno Toad - the shop will know the correct procedure to tighten up the internal wedge (or they should). You hear about slippage issues with internally wedged seat posts quite a bit.

Sy Reene

recommendation:
apply the paste to inside of the frame, just about 1" depth should be fine. wrap some tape around the seatube, where the bottom edge of the tape is at where you want to install the seatpost down in in the seatpost. This will prevent going too far and having to back out. Assembly paste can scratch or mar surfaces, so this would prevent any marring in a visible area on your exposed seatpost.

rsbob 

I have that bike and have not experienced that issue, but I do torque the bolt to spec listed next to the bolt. I am guessing when your bike was assembled, they used some type of anti-seize instead of the paste recommended above so make sure all the old gunk is completely cleaned out first.

freeranger

Same ? popped up not too long ago: Sinking seat post Giant Revolt Advanced 2, D-fuse. - Bike Forums

Sy Reene

It's part of progress https://www.bikeforums.net/road-cycl...-slippage.html

Hypno Toad

Ok ... So I didn't work very hard to search for other threads on the subject ... ... meh

Sy Reene

That's not so much the point. I think the point is that if you read both of the linked threads (and there could be more for all I know), sometimes the solutions don't work (such as the CF paste). Before messing with paste yourself, you may want the shop to suggest and do this in case it were (god forbid) to become a warranty issue.

EDIT: for sake of convenience, this post in one of the threads seems to outline what worked in this particular instance. May be worth considering if applicable to your circumstance https://www.bikeforums.net/20653228-post22.html