giant integrated rack mount seat collar

[hugh stone]

Does anyone have experience with the 'giant integrated rack mount seat collar'?

I'm riding a 2013 Giant Defy 1 which doesn't have any rack mounts on the seat stays so I currently have the rack fitted with a single stay to the brake mounts.

I thought this looked like a more robust option but am interested to hear people's thoughts - particularly on which way it goes (suspect the bolt ends up towards the front and the rack mounts towards the back).

[DavidL]

That one does look like a true seat clamp with the machined flange. Bolt does go to the front.

There are many brands that make these, Salsa is one of them. But most of them are designed as clamps that go on the seatpost tube, and not to replace the seatpost clamp itself.

Depends on the geometry of you frame and where you want the clamp.

- David.

[hugh stone]

Thanks David.

[DavidL]

Just happened to stumble across this Ambrosio MC76 Seatclamp while looking for cassettes of all things:



You really must have the split in the clamp in alignment with the slit in the seat tube. Seeing as most frames have this slit at the back this option would work much better than the Giant one you have found.

- David.

[hugh stone]

Just happened to stumble across this Ambrosio MC76 Seatclamp while looking for cassettes of all things:

You really must have the split in the clamp in alignment with the slit in the seat tube. Seeing as most frames have this slit at the back this option would work much better than the Giant one you have found.

- David.

I was thinking that there could be an issue with having the split in a different spot as it would lead to the two metals rubbing against each other as it tightens. Maybe it's not a problem but it does seem strange.

[DavidL]

Not having the two slits align will result in more damage to the frame surface as there will be a small amount of movement as the clamp it tightened (though in practice this is nothing compared to the general damage seen on frames by the clamp) and because of the small amount of surface friction a little more tension would be required to ensure the clamp is tight.

In all, either options would be fine in practice. But aligned slits would be the only option for perfectionists and engineers.

I would align the slits or get a separate clamp that didn't matter where the slit was.

- David.