Campagnolo EPS unhook

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Posts: 92
Joined: Mon Aug 21, 2017 7:40 am

by Cemicar

In short:
anybody know how to unhook EPS rear derailleur by hand?

A bit Longer Story:
Apparently I did something awful with the zero setting process of my Record EPS, and the rear derailleur is stuck around the 6th sprocket by default. It can shift up 5 times but now down anymore.

Am told we can move the rear derailleur to the desired position in such a case or when the battery dies. ... _07_12.pdf
There is even an instruction video.

However, I still can't figure how to move the rear derailleur manually. It feels like a rock, and is likely to be broken if we push it so hard...

by Weenie

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Joined: Sun Sep 29, 2013 4:34 pm

by androidavies

If the system is still sort of working, there's an "electronics re-set" that you can perform, using your battery charger and a stop watch….

-Plug the charger into the mains socket, with the mains socket switched off.
-Plug the charger into the battery charging port, then turn on the power at the mains socket switch.
-Leave on charge for 1 minute, then switch off the power at the mains socket switch.
-Leave the power OFF for 1 minute.
-Switch the power back on at the socket switch.
-Leave the power on for 2 minutes.
-After 2 minutes, unplug the charger wire from the battery whilst the power is still switched ON.

Repeat the above a 2nd time, just to be sure.

Then have another try with the set up from zero position.

This takes 4 minutes each time. I've had it work successfully on two different bikes that seemed to have had the electronics go haywire.
It doesn't restore function of genuinely faulty components though.

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by Miller

Cemicar wrote:In short:
anybody know how to unhook EPS rear derailleur by hand?

I think I had to do this once. That video is not very helpful in explaining what's happening so I will try.

If you look at the rear der, the actuation mechanism runs through it in a straight line. At the bottom end there's a thing that looks like one side of a front suspension fork with a thinner rod connecting into the main body of the derailleur. On the bit that looks like one side of a suspension fork, the derailleur connects into this part by a small black cylinder at right angles which may have an exclamation mark sticker on the end of it. I think this part contains a spring-loaded ball to lock onto the suspension fork part. It should lock onto the suspension fork part at the end of that part closest to the main body of the der. Check this on your derailleur. If it's out of place, that's your issue, and you're just going to have to use a bit of force to get it back in position, as per the video.

I should just have taken a photo...

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by graeme_f_k

Can we back up a bit, Cemicar?
Why exactly do you want to unhook?
You may be able to just do a new zero set to fix the setting issue.

You may not need to use the Ride Back Home function at all and doing so won't help you do anything much more than just that - Ride Back Home.

If you can get into zero set mode, then Androidavies method works OK though the stopwatch is not necessary, you just need to wait more than about 40 sec or so in "switched off" state and strictly, you don't need the charger although there are some extremely uncommon circumstances where it helps. It's applicable usually in cases with Firmware version 37 or 44 (see the white tag on the Interface cable, can usually be pulled clear of the frame unless the extension cable has been used).

If you have a later v2 (FW version 50), this process does no harm but it doesn't help, either.
A Tech-Reps work is never done ...
Head Tech, Campagnolo main UK ASC

Posts: 92
Joined: Mon Aug 21, 2017 7:40 am

by Cemicar

Hey, first off, thanks for your great supports, all three of you.

I will have some time this weekend and try your suggestions and post feedbacks. Yeah, perhaps I may end up solving my issue with reset, or zero settings.

Meanwhile, this is a photo of my rear derailleur.

Looks like the same state in the figure below, thus it's hooked so I can't move it.

Posts: 92
Joined: Mon Aug 21, 2017 7:40 am

by Cemicar


I kinda solved my issue. It appears that, if we keep pressing the levers in zero setting mode despite some warning 'beep' sounds, we can move the rear derailleur anywhere... My derailleur was stuck at the middle of the chain stays, and by holding the thumb lever, it successfully came back to the upper position.

Thanks everybody.

I may see why Campy EPS setup is ostensibly limited to the some licensed shops, although in this case I was just a moron.

by Weenie

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by spookyload

There is a get home disconnect, but also don't forget if it takes a blow, it can disconnect itself to prevent damage as well. The procedure for resetting it is equally vague, but I found Youtube videos that show it very well.

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