After you leave Yosemite, get on hwy 49 and head north, it's a great ride and it conects to hwy 89 just north of Sierra City. from there head north on hwy 89 to Quincy, then Greenville. At Canyon Dam take hwy 147 to Westwood, there is a great place to eat Called The Old mill Cafe, in Westwood there is a county road A-21 that connect to Hwy 44. That turns into hwy 89 and cuts over to Interstate 5, you are only on 5 for a short distance. Take hwy 97 to Klamath Falls, and it's a short hop to Crater Lake from there. If you only have 3 days it's mostly going to be riding not exploring, but this is a great route and lots of great views. Have fun, and maybe I'll see you at the Old Mill Cafe, by the way my son owns the cafe!!!!!
Any fool can criticize,condem and complain and most fools do. Ben Franklin