Hi Mark -
Google Earth does show a trail called 'Yellow Banks' but I'm not sure if it actually gets you to the surf spot. The cliffs on that part of the island would make getting down from the top damn tough if not impossible if the beach trail didn't get you there.
If you rounded up a few guys with some $$$ and time off on a good swell, you might consider chartering a dive boat or private yacht. There are definitely some charter boats available and if YB isn't breaking (and it rarely is), you could head elsewhere.
I've been to several of the islands and surfing wasn't usually the objective. Getting dropped off at Prisoner's and backpacking over the mountain to Scorpion is unbelieveable. We overnighted at Del Norte campsite and watched humpback whales from the top. The 15 mile hike out to Point Bennett and back (San Miguel Island) takes you to one of the world's finest pinniped haul outs... a true 'National Geographic' experience.
Everysurfer , years ago some fishing boats would run surf trips from Channel island harbour out to the islands , they would leave around midnight , get to the backside of the islands about dawn , you got to surf all morning , they moved the boat to wherever you wanted , you could take as many boards as you liked and they had a kitchen to feed you and a few bunks for sleeping I think it was a min of twenty surfers to make it viable and we all got to fish on the way back. I dont know if they still run the trips ? Remember I said it was fishing boats no luxury involved dont take your wife , but a lot of fun.
expect people at most every south swell spot. anymore, when souths hit, a whole lot of boats converge on the islands-running out of three harbors in the vicinity. there are some private boats that charter for surf expeditions.
try to go before any major swell is predicted.
a google search for "yellow banks channel islands" brought up this site - http://www.adventuresailingventura.com/surf-trip-charters-to-the-channel...
i have no idea if they still exist
there is no need to name spots, even marginal ones that rarely break, and are hard to get to. Take this stuff to Private Messages, please.
Orale` Mr. Melville.