What os the point of three bottle bosses

I have a bike with three bottle bosses on the top of the downtube. I used a wolftooth brad to attach two bottle cages successfully for 6 months or so. Today one of the bottles snapped off when the Brad broke.

Anyone know what use the three bottle bosses is? They are all evenly spaced so you can mount a bottle cage with either two. Anyone know a good way to use it to mount an extra bottle? The brad-4 is not a very good option in this case it seems.

Suspect it is to offer two alternative mounting positions for a single bottle. Lower set for aero position, upper set for easier access or when the seat tube cage is also in use. Sorry no suggestions as to how to use for two cages simultaneously.



I vaguely remember seeing, many years ago at a bike show, a very Heath Robinson looking contraption that consisted of 2 cages, each angled at about 30 degrees, to facilitate this idea.

EDIT: see M-Wave Adapter for 2 Bottle Holders | Bikester.co.uk - this is quite similar

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Use lower two to accommodate taller bottle or partial frame bag, upper to make room for wider seat-tube-mounted bottle or make dt bottle easier to reach. But better one larger bottle than attempting two of any size on the dt alone imho.

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Simple Answer is bikepacking or touring. The three lugs means you can carry larger items, while not damaging the bosses or frame.

On my 2014 Cervelo S5 I have 3 bolts on the downtube. If I was only running one bottle i’de have the downtube cage in the lower position.