Bending Front Derailleur Cage

[Robert Lee]

I ride a Specialized Roubaix Expert, with FSA compact cranks and Ultegra
components. I have chain rub that can't be removed by setting the limit
screws or rotating the front derailleur. My bike shop wants to bend the
front derailleur cage, but I have resisted letting them do that. Should
I agree to it?

 

[Qui si parla Campagnolo]

Robert Lee wrote:
> I ride a Specialized Roubaix Expert, with FSA compact cranks and Ultegra
> components. I have chain rub that can't be removed by setting the limit
> screws or rotating the front derailleur. My bike shop wants to bend the
> front derailleur cage, but I have resisted letting them do that. Should
> I agree to it?

FIRST, ensure that when in biggest cog and small ring, the chain is
almost tickling the cage, then make sure the cable is TIGHT, then see
if the FD goes over far enough, in smallest cog and big ring. It's all
based on start postion and tight cable, or elsewise the FD doesn't go
far enough. I have adjusted many 6500/6600 FD on FSA cranks as well as
others and haven't had to bend it yet.

 

[Stephen Greenwood]

Robert Lee wrote:
> I ride a Specialized Roubaix Expert, with FSA compact cranks and Ultegra
> components. I have chain rub that can't be removed by setting the limit
> screws or rotating the front derailleur. My bike shop wants to bend the
> front derailleur cage, but I have resisted letting them do that. Should
> I agree to it?

If the crank, chainwheels, derailer, and bottom bracket are the
original equipment that came with bicycle, it should be possible to
achieve proper function by proper adjustment. If any of the above
components have been replaced, it's possible that you have a
combination that doesn't work. For example, a replacement bottom
bracket with too long a spindle might move your outer chainwheel past
the range of your derailer. This is not the most likely explanation,
but it's something to consider.

Stephen Greenwood