I'm planning to ride around Mt Hood in a couple of weeks and have hear conflicting opinions on the I-84 sections and specifically the Tooth Rock Tunnel. Anyone have thoughts?
First off, which direction are you heading on 84, westbound or eastbound? Only the eastbound section goes through the tunnel, and I would definitely NOT ride it
as there is no shoulder there. But the old Historic Columbia River Hwy is closed to cars and bypasses the tunnel. That's the preferred bike routing through there. (You'll have to navigate a large flight of stairs, though.)
I would use the Historic Columbia River Hwy as much as possible between Troutdale and Hood River. With it, you get to stay off 84 except for the last 10-15 miles east of Cascade Locks, and a section around Bonneville Dam. (As for the latter, they are finishing up a section of the old highway from Yeon State Park and Bonneville. It should be done very soon.) And all sections of HCRH east of Bonneville are closed to cars!
If you haven't already checked it out, you should look at the Columbia Gorge Bike Map put out by ODOT: http://www.oregon.gov/ODOT/HWY/BIKEPED/docs/ColumbiaGorgeBikeMap.pdf
If your heart is set on riding 84, it's not too bad (besides Toothrock Tunnel.) The shoulder is pretty wide except for right around Shellrock Mtn (which is unavoidable as the old road is not open around there.) Expect a fair amount of debris in the shoulder, though.
I was thinking of riding over Lolo Pass rather than route 35 to Government Camp. Anyone have thoughts on Lolo Pass and the possible dirt sections (also conflicting reports).
Lolo Pass is a great route! Quiet and scenic. It can be steep in sections, and the west side will have high tension powerlines overhead. The "dirt" section is about 5 miles of gravel road. I found it rideable with only a few parts where the gravel felt loose. And it wasn't bad for descending, either. Of course, people's tolerance of gravel roads vary widely. I have 700X35C tires on my touring bike, so if you had 28mm wide tires you might not enjoy it as much.
Here's a few photos from Lolo Pass Road.