My two cents...

My Jib and main halyards are 5/16" tapered down to 3/16" core on the last 20' of the working end. However I also pulled the core out of the first 10' of the tailing end (just short of the spinlock jam cleats when hoisted)...not a good decision. With the core removed the cover is very soft/pliable and tangles very easily when tryig to douse. Also, when I replace my spinnaker halyard I will no longer use a shackle. It lets go every once in a while. I'd rather tie the halyward to the spinny as I do the sheets. Tieing has never failed me.

George

:: Roger,
::
:: Currently the majority of the fleet is using 5/16" line
:: tapered down to 3/16" core. I usually have the last 20'
:: just the spectra core to save on weight aloft when it is
:: hoisted. This is the case for the jib and the main
:: halyards. On the spinnaker I have recently gone down to
:: 1/4" line tapered down to 1/8" core. This is plenty
:: strong enough for our boats and still not too small to
:: handle.
::
:: A halyard 3/8" is going to be way too big for our boats.
:: Some clutches do have a hard time with the smaller 5/16"
:: line, but there are ones that work. We have a halyard
:: tensioning system, so if it slips through the clutch a
:: little it is not hard to adjust. Without this system you
:: are far more sensitive to the line slipping through the
:: clutch.
::
:: Hope that helps.
::

:: -Jason

::
:: :: I'm looking at Scott Easons helpful list of line sizes
:: :: but am still confused. My boat has old Lewmar rope
:: :: clutches which require 3/8" line to hold. I tried an
:: :: extra halyard 3/8" tapered to 5/16th. Its too large to
:: :: pass through the sheave at the top which is small and
:: :: has a guard.
::
:: :: Im assuming the answer is to use a thinner taperd line
:: :: and replace the rope clutch. What are others using? The
:: :: tuning guide says 3/16th technora but doesnt say the
:: :: cover size