Dura Ace 12speed Firmware update, not so wireless...

No quite the stuff I normally cover on the main channel, but I thought this might help some people out there trying to update the firmware on the new Shimano 12speed shift levers (Dura Ace 9270 and Ultegra 8170). Even though they are wireless, you can't update the firmware wirelessly ...which might cause some confusion.

Part used for connecting the levers:
EW-SD300 (1400mm in my case)
EW-JC302 Junction

Check https://bettershifting.com for the latest information
(This video might be outdated when you watch this)

Main Channel:    / ridesofjapan  
Instagram:   / ridesofjapan  

Timestamps:
0:00 Wireless STI shift lever firmware update not possible
0:43 Three ways to update the STI's Wired
1:59 Update by connecting the STI directly to the battery
3:05 WARNING, don't forget to plug the battery!
4:05 Update by connecting the STI directly to the FD Cable with a a junction
5:17 Summery