Finally got a chance to ride from Xindian to Toucheng via Bei Yi up to Fulong and back via the 106. I’ve done the clockwise version, which is a biotch bc all the elevation gain is in the last 60km from Toucheng back to Helen’s Coffee in Shiding.
If you’re out on BeiYi from Helen’s Coffee down to Ping Lin early enough, you may get a glance of the fog covering the reservoir.
Otherwise, lots of fun, definitely worth taking a nice (not so sunny day) to attempt. Happy to give more details over on The Taipei Cycling Routes thread if you guys are curious about the checkpoints and feed stations.