I just replaced all the halyards on Jalapeno (#46). I used 5/16" Yale
Crystalyne for the Jib halyards, and 5/16" Yale Vizzion for the
Spinnaker halyards. I left them coated the whole way for longer life,
though many (most?) folks strip the cover. I've had uncoated halyards
break after 3 seasons due to UV exposure and chafe, so I figured I'd
pay for the weight aloft to have them last longer. I had to make a
couple mast changes to leave them covered: The sheaves in my mast
were for wire, so I got new ones from Ballenger for rope, and the
halyard sheave box was too too narrow for the splice on 5/16" rope. I
had to file out the spinaker sheave area (the jib was OK, partially
due to a different kind of eye splice on the Technora rope).
You'll want to stick to Technora or something equally low stretch for
the Jib Halyards. The Spin halyard can deal with slightly stretchier
material. You'll want at least 5/16" at the working end; 1/4" is too
skinny for most crew to be very happy with, and may not hold well in
cleats and line clutches.
I used 1/4" Yale Crystalyne for the main halyard. This has plenty of
strength and cleats fine in my spinlock clutch.
I used #5 Tylaska Trigger release shackles on the jib and spin
halyards. These are expensive ($100 each), but your foredeck will
love you for them. I use them on my spin sheets as well. If your
foredeck has fragile fingers (long fingernails?) you can buy them a
fid and make life really easy. A plug for these shackles: I've done 6
seasons and many hundreds of races on my Santana 35 with the same #8
Tylaskas and never had any issue with them. The ability to release
them under load with a fid has saved us serious trouble before.
I just used a Wichard key pin shackle for the main.
Lots of other opinions out there--I resorted to the gear above based
on experience with my Santana 35. I use the same stuff (slightly
larger) on the Santana and it has been well tested.
hope this helps,
--brendan