The posted speed is 50 mph, but the signs posting the speed are few and far between. There were four of us in our car looking out the windows last weekend, and none of us saw a sign posting the speed limit for approximately 25 miles as we entered Idaho driving West on Highway 12 from Lolo Pass. Even after I was ticketed, we went another 8-10 miles before seeing a sign posting the speed. And another 8-12 miles after that before the second sign. 50 mph is under the 55 mph we consider the “basic rule” speed for rural 2-lane roads in many Western states, so it should be posted conspicuously and frequently. And 55 mph would be a safe speed on the section of Highway 12 where I was ticketed—at least in the summer with dry pavement. The lack of signage is especially misleading since the yellow caution signs for curves included some that recommended a speed of 50 mph! There were a lot of these caution signs for curves, but few signs posting the speed limit. And I suspect we passed none before I was ticketed.