This idiot changed to some new wider tyres and in doing so has rubbed the front mech 8150 di2 cable. One minute I had gears, next minute the entire system is dead..no lights on rear mech, and nothing in app. Could this broken cable have caused the entire system to shut down to the point of having no power at all? I thought the rear mech was the brains in the new system, which makes me concerned I might have done some permanent damageš¬.
I guess next steps are replacing the cable..what length would I need? It's a 2025 Cube Agree C62, but I have no idea where the battery is to work out the length! The shortest they do is 150mm. Any ideas?
by goatkarma
6 Comments
I would check the manual, sometimes they detail the cable / wire lengths in the build instructions.
Failing that, remove the old, measure and buy a replacement.
If not confident, local bike shop will be able to sort it out
The battery is under a plastic cover underneath the bottom bracket. Flip the bike over, you’ll see a black plastic piece with two bolts and a lightning symbol on there. Unscrew the two bolts and that’s where the battery is.
On 6870 if a component lost connection the whole system needed detaching from the battery and then re-initialising using the dongle and Etube, maybe that’s the issue
As to length measure it with a piece of string. It’s probably not long, depends on where your B junction connector is
Thought I just saw some pics from Unbound Gravel this year where someone ran their Di2 cable in front of the FD to avoid rubbing on wider rear tires and race muck. They also taped it down if I recall correctly. Sorry, not sure which site I saw this on.
Don’t worry, you haven’t ruined the whole system. Just pull the damaged wire out, measure and replace it.