You should take Xinguang Rd. instead of 106. If you’re heading east from directly in front of the zoo, turn right onto Xinguang Rd. instead of crossing the bridge and following the 106. If you follow Xinguang (which basically runs parallel to 106 but across the river), it will hit the 106 just before that Hi-life/7-11 intersection. This avoids a lot of the potholes and traffic through Shenkeng.
Also, for a shorter route than going all the way to Pinglin, turning right at that Hi-Life/7-11 intersection, when you get to that next Hi-life where you turn left to go past Huafan Daxue and onto Pinglin, take the right instead. Going about 2km along this road, there’s another intersection where going either left or right (the left is steeper for the first 5km and then flat for the next 4km while the right is a steady and not as steep 7km) will eventually bring you to the No. 9 and back down to Xindian. This is my typical “training” route that I do twice a week: not much incline warming up to that last Hi-life, get some food, push as hard I can uphill, then have fun whizzing down to Xindian and the bike path back home to cool down.
“going 2km along this road, there’s another intersection”: that’s when you’re in a small cluster of houses that looks like its own mini village.
those two choices are the 42-1 to the left and the 42 to the right. the 42-1 requires a right turn at the T junction at the very top of the climb, when you’re in the black pine forest. that’s about spot on 500m if you have an altimeter. Very pretty road, recently resurfaced, but no lights. the 42 is a bit bigger and less steep.