If the weather isn't great on the west side, I'd be tempted to go up to Alturas. Just west of town on 299 is a county road #73 (aka Crowder Flat Road). 50 miles of gravel through the Modoc NF into the Fremont NF of southern OR. Lots of pot hole lakes for fishing. NF Lofton Reservoir CG is a nice area. A lot of the development roads in the Fremont area are paved, so nice road bike riding. Most CG in this area don't have water. Plenty of back routes to get you to Bend.
2x Newberry Crater National Monument. A very large obsidian flow hike inside the crater is really amazing. Little Crater CG on Paulina lake is very nice if you can get a spot.
After all the usual activities in Bend and Sisters, consider heading west over McKenzie Pass (Hwy 242 out of Sisters) very pretty, with an impressive lava flow at the top of the pass. Narrow curvy road, but very doable. Take some FS development roads to the south and east through the Willamette and Umpqua NF back over to the Diamond lake area. Time will go fast, jump on 97 south but when you get to Klamath Falls consider taking 39 SE toward Hatfield, or just north of Doris head east on 161 toward Hatfield. Then back route it to the Lava Beds National Monument Caves before heading home.
If you use a charting/mapping program on a laptop, like Delorme or MS that can import waypoints, I have an excel file or text file you can PM me for which will locate 566 NF, State Park and National parks and monuments in Oregon by GPS position. Makes free form trips in the region easy.
Everybody on the west coast should be checking out central / eastern Oregon as the last total eclipse of the sun in the US, until almost 2050, will happen on 8/21/2017
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