China Hat/East Fort Rock are an absolute blast if you ride the right trails. It will be very dusty this time of year, but spread out 30 sec. and you will be fine. I just rode there 2 weeks ago and we had a blast. My personal favorite is: stage at 2150, take trail#70 to #80 to #90 and then back. It is 40+ miles loop and we call it Disneyland. It is not technical, but 3rd gear flying through berms and weaving through Juniper is a blast. Staging area 2510 is about 30 min. out of Bend on Hwy 20.
If you are around Portland Metro, then Hood River is some great singletrack, but may be closed due to fire season.
Diamond Mill is the most technical on the coast, but is hard to navigate without someone who knows the area. Jordan Creek is also a blast and can be easy to navigate with the maps at the OHV.
I like Capitol Forest, especially this time of year with it being dry because it is mostly in the timber. It a bit hard to navigate, but you can hit most of the trails with a good map. Probably the best place to stage out of is Rock Candy or Straddline. These are both in Washington State about 2 hrs. north of Portland near Olympia.
If you want to tackle an event, the is a great Poker Run at Capital Forest, or a 6hr race at Straddline with endurocross, mx and singletrack sections. I think these are both tomorrow.
Have a blast and enjoy the PNW! We have a paradise to ride in, just dont tell anyone!