Horner's front derailleur problems

[graviT]

Sorry if this has been posted before but I am curious if anyone knows what gruppo Horner is riding. Unable to downshift on the front twice in one race? I'm just curious if this is a Di2 issue as it seems unlikely to happen with a mechanical front derailleur.

graviT

 

[Magnus]

It seems unlikely to happen with Di2 as well.

I think he is on Di2. At least he was in the Tour of California. And on stage 13.

 

[Badeend]

It seems unlikely to happen with Di2 as well.

Not really. If the cable isnt tight enough in the shifter and you hit a bump when your hand is resting on the shifter, its possible it comes lose, more people have experienced this problem.
Horner rides DI2, i think Cancellara was the only rider (from radioshack) to ride the mechanical version at this Tour

 

[Magnus]

Not really. If the cable isnt tight enough in the shifter and you hit a bump when your hand is resting on the shifter, its possible it comes lose, more people have experienced this problem.
Horner rides DI2, i think Cancellara was the only rider (from radioshack) to ride the mechanical version at this Tour

What do you mean by the cable not being tight enough?
Either it's plugged in or it isn't. I don't see how the hand resting on the hood or not would make a difference.

If it was a mechanical front derailleur I could see how you could pull the cable loose when shifting if it isn't properly fastened.

 

[graviT]

Not really. If the cable isnt tight enough in the shifter and you hit a bump when your hand is resting on the shifter, its possible it comes lose, more people have experienced this problem.

I've read about that as well. Seems that most of the time if a mechanical derailleur is good at the start of the day it will be good all day, barring crashes or other incidents.

Di2 not so much.

graviT

 

[graviT]

Either it's plugged in or it isn't. I don't see how the hand resting on the hood or not would make a difference.

It is a socket connection. A pull on the cable can unplug it. I've read reports of people unplugging the cable while gripping/twisting under hard efforts, probably aided by not enough slack in the cable under the tape. That's not going to happen with a mechanical system.

If it was a mechanical front derailleur I could see how you could pull the cable loose when shifting if it isn't properly fastened.

Hard to believe a professional mechanic, or any competent mechanic for that matter, would fail to tighten the cable retention bolt. Not to mention that if that happened, it would shift into the smaller chain ring, not get stuck in the big ring.

graviT

 

[Magnus]

It is a socket connection. A pull on the cable can unplug it. I've read reports of people unplugging the cable while gripping/twisting under hard efforts, probably aided by not enough slack in the cable under the tape. That's not going to happen with a mechanical system.

I could see that happening I guess. But to use your own words it's hard to believe that a mechanic would fail to install things with enough slack. Especially considering how little you twist the handlebars when cornering.

I'm convinced that Horner was riding with Di2, but I still think it's unlikely to happen using Di2 that you can't shift with the FD. I've never experienced it before (nor heard of it).

 

[avanti]

Is it possible that water got into the system - either on the road or during nighly washing.

Did Horner get a replacement bike after the failure?

 

[Badeend]

You can press the cable in by hand, but there is a tool to firmly connect it into the shifter

Its impossible the mecanics dont use it but it's always possible he thought it was in 100% when it wasnt.

When the connectors of the cable and shifter have contact it will shift (even when not 100% correctly installed), it can shift for a very long time like this. But if your hands are on the shifters and you hit a hole in the road it's maybe just a millimeter that your shifter moves, but that could be enough to lose contact. If the cable is too much tightened it can also lose contact when its not connected properly.