Last year my Di2 front der. went out. I didn’t think too much about it and replaced it. Now, about 8 months later the replacement is broken. The product is a FD-R8050 ULTEGRA DI2 Front DERAILLEUR.
Yes, the battery is charged.
My LBS theorizes that I sweat so much that it is rusting out the components, but that is just their guess. I do sweat heavily, about 3 qts per hour on the bike and a little on the salty side, but surely Shimano realizes that people are going to to sweat while using their products. Has anyone heard of problems with the front der.? Any ideas what could be causing this?
It’s might be possible that the FD is fine, but there is a kink in one of the DI2 cables, especially the battery cable. If the battery cable kinks, it can transmit weaker power to the FD, so it shifts only partway, or not at all. Even when the battery is fully charged.
This can be hard for the LBS to figure out as well - mine didn’t even figure it out, but they diligently went thru the entire cable by cable computer check for system integrity (which I’m guessing unkinked my cable) and it suddenly worked fine. I had the problem again when I shipped and reassembled my bike; this time I fixed it myself.
Note that my cable wasn’t horribly kinked or anything like that - it was bent just enough to cause FD trouble (and eventually charging trouble, but it still charged.)
Good point. At the LBS, we plugged in a new der. to my bike and it shifted fine. But to complete the test, I should plug my bad der. into my wife’s bike and make sure that the problem is really the front der.
Sweat rate is just a rough estimate. Weigh yourself before and after a workout. Subtract the weight of anything you consume. I did it a couple times after a 1 hour workout and consistently got 3 qts on the bike and 4 qts while running.
Good point. At the LBS, we plugged in a new der. to my bike and it shifted fine. But to complete the test, I should plug my bad der. into my wife’s bike and make sure that the problem is really the front der.
You need to plug it in to a PCE1 to do an error check. LBS should have one. Only way to figure out whether a cable is actually the problem. Bad cables can cause all sorts of weird issues.
Don’t forget that you are also losing water through the respiratory process, as the by products of combustion are CO2 and H2O, so not all weight loss on the bike can be directly attributable to perspiration. 3/4 of a gallon in sweat is astonishing if that’s accurate.
Brought it to the LBS. They:
Took off anything they could, which wasn’t much. Sprayed it down with White Lightning Clean StreakSprayed it down with Tri-FlowUsed an air compressor on itSprayed alcohol on the contacts
It appears to be working better now. At least it moves when they plugged it into a bike at the shop. They agreed that it looked like corrosion from sweat. I’ll give it a try on my bike as soon as I can.