Harold,
Others may disagree, but if you are not a serious racer, I really don't see the need for a fourth halyard. For me, the main and jib halyard get used all the time, and the spinnaker halyard only occasionally. The spinnaker halyard is my "spare". I use it to hoist the dinghy to the foredeck, to get to the masthead in a bosun's chair, and oh yeah, fly the chute! If I were you, I would carefully check the condition of each of your current halyards, and replace if necessary. Also, don't go "up" a size thinking you are doing a good thing. You will only add chafe in a bunch of places. The boat is designed for 3/8" halyards. I would just replace the sheaves that are in use with roller bearing types. If/when you add a halyard, then you can change the other sheaves. Regarding the VHF, I would upgrade the coax going to the antenna. From memory I can't tell you what a good or bad coax is, but an electronics expert can easily do so. A high quality coax will greatly improve your VHF performance, even more than replacing the antenna. Hope this helps.

Hi, Tom. When you say 3/8 inch, do you mean for the mainsail halyard as well? I think mine is fatter, but that was the size when I purchased the boat.

Ben,
Yes, I do. If you look in the Owner's Manual for the MkI and/or MkII, you will see that all of the halyards are spec'd at 3/8" low stretch. Some owners have tried going up a size (to 7/16"). It has sort of worked, but those who have looked at all of the blocks and sheaves carefully have found that the 7/16" halyards don't quite fit, and create additional chafe and additional friction. Sheets on the other hand, are spec'd at 7/16". On my MkI (without a turning block) I went up to 1/2" for the genoa sheets without a problem. Your boat, your choice.

[QUOTE=TomSoko;15427]Ben,
Yes, I do. If you look in the Owner's Manual for the MkI and/or MkII, you will see that all of the halyards are spec'd at 3/8" low stretch. Some owners have tried going up a size (to 7/16"). It has sort of worked, but those who have looked at all of the blocks and sheaves carefully have found that the 7/16" halyards don't quite fit, and create additional chafe and additional friction. Sheets on the other hand, are spec'd at 7/16". On my MkI (without a turning block) I went up to 1/2" for the genoa sheets without a problem. Your boat, your choice.[/QUOTE]

With mid-spec lowstretch lines like VPC you could go the other way and go down a size. I went with VPC for my main but out of caution stayed with the standard size. I defintely recommend VPC and if I did it again would likely go down a size.

I give, what is vpc?

Never mind didn't check the web for vpc

[QUOTE=ciscocat;15455]Never mind didn't check the web for vpc[/QUOTE]

Sorry should have said New England Ropes VPC to make it a bit clearer. It gives performance much closer to expensive high performance lines targeted to pure racers at a price point cuisers with a performance craving can tolerate.