A friend has an ebike with Di2 Alfine 8 gearing that is having intermittent shifting issues between Gears 5-6 in both directions.
I have not played with Di2 hub gears before and most of the information on the net (remarkably little) doesn’t refer to the Alfine 8 version. I understand that the Di2 actuator is the same for 8sp and 11sp hub gears. The Shimano dealers manual doesn’t give any useful troubleshooting advice, effectively saying “tweak this and see if it makes better, otherwise tweak it the other way and see.”
Because this hub has the same issue changing up and down, I don’t think this adjustment will solve things and, if unlucky, may make it worse. The tweaking is effectively the same as tightening or loosening a gear cable. There is also an adjustment for speed of shifting but I don’t know what is the best shift speed for an ebike.
Does anybody here have experience with diagnosing and adjusting Di2 hub gears?