I am an avid cyclist, 8000 km/y.
My bike frame is entirely aluminum, the rims and spokes are aluminuim, the bearings are sealed cartridge bearings 316 SS with ceramic balls.
Stepping through all the parts
, all are corrosion resistant, except for.
The chain, I am quite sure that slathering some vasoline on it would work, I would just remove the chain, and seat and store them below. I do have a 100% titanium chain but that ain't staying outside anyway.
I think for a 7 day sail I would remove the wheels, and store in a locker, I have wheel
I would get a couple of quick release clamps and attach these to the outer hull
, then I would clamp the bike on and go.
For an ocean passage
I would get a bike case, and store in a locker.
The bike transport cases are for airplanes, these cost about $150 I think and are robust plastic cases, that have fittings for all the wheels etc inside. See JensonUSA.
Lastly there is a Lapierre Mountain bike that is designed to fold into a case, This bike is a very good bike, not to be compared with the classic foldable bike.
I have not done this as yet because all of my sailing vacations have been very sail oriented, and all of my bike vacations have been very bike oriented, and neither have been for very long times. (I guess I am a little too focused at times)