Ultegra 6870 Di2 rear mech issue
Trying to get to the bottom of a problem on my wifes bike.
I upgraded it to Di2 a couple of months back and it's been performing great.
However after coming back from a weeks training camp where the bike was taken in a hard box over to Spain, the rear mech lunched itself into the wheel and bent the replacable hanger whilst on a turbo ride changing down to low gears.
The theory is it got slapped about a bit on the way home as two of the internal straps are broken and corner of the box was greasy where the mech would have come into contact with it. I know, forgot to remove it, but it was wrapped in bubble wrap well and nothing really untoward noticed whilst unpacking.
I've bought and fitted a new hanger, checked it for alignment and find that the Di2 rear mech seems to be damaged as it won't shift correctly in the larger rings at the back (rattles like it isn't positioned correctly), and requires the adjustment to be on 13/16 to get it to change half decently.
At first I thought the cage was bent so swapped it (the cage) with a normal Ultegra rear mech as they are identical. Still looked twisted on the Di2 and the Di2 cage looks square on the std mech.
All in all I am a bit stumped as I'm struggling to believe what has happened.
Anybody had a mech get damaged and twisted and it wasn't the cage, and any ideas of what might fix it.
I've also checked the mounting bolt on the mech and that seems square, so the problem must be in the parralellogram mechanism somewhere.
Pics are included below if it helps, although they are difficult to take precisely.
https://www.dropbox.com/sh/vxiebj75b0p4 ... u_Pma?dl=0
I upgraded it to Di2 a couple of months back and it's been performing great.
However after coming back from a weeks training camp where the bike was taken in a hard box over to Spain, the rear mech lunched itself into the wheel and bent the replacable hanger whilst on a turbo ride changing down to low gears.
The theory is it got slapped about a bit on the way home as two of the internal straps are broken and corner of the box was greasy where the mech would have come into contact with it. I know, forgot to remove it, but it was wrapped in bubble wrap well and nothing really untoward noticed whilst unpacking.
I've bought and fitted a new hanger, checked it for alignment and find that the Di2 rear mech seems to be damaged as it won't shift correctly in the larger rings at the back (rattles like it isn't positioned correctly), and requires the adjustment to be on 13/16 to get it to change half decently.
At first I thought the cage was bent so swapped it (the cage) with a normal Ultegra rear mech as they are identical. Still looked twisted on the Di2 and the Di2 cage looks square on the std mech.
All in all I am a bit stumped as I'm struggling to believe what has happened.
Anybody had a mech get damaged and twisted and it wasn't the cage, and any ideas of what might fix it.
I've also checked the mounting bolt on the mech and that seems square, so the problem must be in the parralellogram mechanism somewhere.
Pics are included below if it helps, although they are difficult to take precisely.
https://www.dropbox.com/sh/vxiebj75b0p4 ... u_Pma?dl=0
0
Comments
-
If it was well wrapped in bubble wrap it seems far from certain that it was damaged in transit. Are you sure the bike didn't move when on the turbo and get damaged in the resulting incident you describe? It can be easy to clamp it slightly sub-optimally....FFS! Harden up and grow a pair
0 -
Not sure what happened or when to be honest. Finally threw the towel in and ordered a new rear mech. Fitted it an hour ago and the shifting is back to normal.
Oddly enough, out of the box the mech (Ultergra 8050 SS) has a slight kink in the cage but when on the bike it is square. At least a lot more square than the old one.
Still have a bit of a grinding noise when in higher gears but, through a combination of swapping cassettes and rear wheels on 2 bikes it seems the noise is only generated with the new Ultegra 11-32 cassette on her 'best' mavic wheels and when on this bike with Di2. Any other combination of cassette, wheel and bike doesn't make any noise.
She'll be riding it out on the road this coming week so will see if it beds in ok.0
