Take the 6:43 am Amtrak from Solana Beach to San Juan Capistrano, $17 and use the option to add a bike $0.
Last weekend rode the train to Irvine and biked back to Solana beach through Camp Pendleton. Beautiful day and ride down the coast highway!!
I'm up for doing that again if anyone is interested. It was 60 miles total, not to hilly!