PatrickGSR94

I usually ride my road bike commuter several times per week. Last week it sat from Thursday until the following Friday. Friday morning I rode to work, and shifting to the big ring seemed to get progressively harder and harder, until finally it got stuck and wouldn't shift back to the small ring unless I physically pushed the derailleur cage in the small ring.

My first thought was cables. But with the cable removed the shifter internals and the cable seemed to move freely. The FD cage was very hard to move by hand, however. The spring was quite dirty. I sprayed some degreaser and a little silicone spray onto the pivot areas of the FD, and that freed it up a little. But after connecting the cable, it's still extremely hard to get it to shift up. I'm afraid of breaking something in the 105-5700 brifter unit.

Is there something else I should apply to get this thing to move easier? I tried loosening the cable tension slightly, but no change, still very difficult to shift.

Guess I'll be riding to work tomorrow with only the 34 front ring and 11-28 10sp cassette.

ypsetihw

if cleaning and lubing the FD springs and hinges seemed to help, then I would continue to do so until it fixes it. honestly if the cable and shifter are free, that leaves only one thing, which is the FD itself. take it apart, clean it thoroughly, then clean it again. a little elbow grease goes a long way. if you are riding in the rain and don't have a front fender (or have a fender but no mud guard) then all manner of crap is getting thrown up into your drivetrain, and it's only a matter of time. corrosion could be the culprit as well, and if that's the case, then cleaning and lubing might not fix it. only way to know is to try.

post some pictures if you get a chance.

PatrickGSR94

Yeah I did get caught in a rain shower on Thursday week before last, without my clip-on fenders that I normally use.

I just removed the FD and put a few drops of Tri-Flow on all 8 pivot points, tried to move it in and out a bunch of times, then put it back on. Reconnected the cable and it still feels pretty stiff. Maybe part of the problem is the cable. I'll have to pick one up at the LBS tomorrow and see if that + new housing helps. These are drop bars with under-tape routing.

dsbrantjr

Carefully check the shift wire inside your brifter for fraying. If you catch it before it breaks you will be spared the exquisite torture of getting the broken-off end out. Check this often, especially when there is a sudden change in shift behavior, like you have experienced. The wire may seem to move freely when it is not under tension.

cyccommute 

While the cable could be fraying and it would be worth inspecting, I suspect the outer cable. I've had lots of outer cable housing where the rods making up the housing break loose from the plastic cladding and jam the cable. It looks a bit like this




As you shift, the rods try to slip through whole in the ferrule with the cable and jam things up.

bikecrate

I had this happen to my FD a couple of weeks ago. I had vacationed at the beach and I believe the salt air and extra sand on the road added to an already gunked up FD. Extensive cleaning fixed it. Also my rear brake cable seized up the following week for the same reasons. Lubing fixed that.

PatrickGSR94

Thanks guys, I'll be checking out the cable and housing soon. Didn't ride today due to heavy rains.

PatrickGSR94

Just replaced the cable and housing. Shifting still feels VERY stiff. I wonder if the plastic guide underneath the BB needs to be replaced. Maybe the cable has been cutting into it too much. It's got nearly 11,000 miles on it since I bought the bike.

Dyskolos

I had a similar issue when sand and dirt fouled up the guide tubing under the BB. I bought a roll of the tubing and now replace it every time I replace cables and housing.

fietsbob

Un hook the cable.. a high normal FD will have the spring push it into the big ring.

PatrickGSR94

So apparently the issue was two-fold. Part of it was that I had installed the FD cable incorrectly on the FD fixing bolt. There's a little tab next to the washer on the fixing bolt, and I routed the cable in between the bolt threads and that tab. That reduced leverage on the FD and made it more difficult to shift. Guy at the LBS noticed it immediately and said he sees it a lot. The FD-5700 instruction sheet isn't clear on that part. He put the cable back in going OVER the tab, which moves the cable away from the fulcrum point on the FD, and makes shifting much easier.

However, that doesn't explain why it started getting sticky/stiff-feeling in the first place, last week. I think it was a combination of the FD being quite dirty from riding in the rain with no fenders the week before, then the bike sitting for a week, AND a worn BB shell cable guide. I went ahead and installed a new guide anyway.

So now, front shifting is LIKE BUTTA once again. Almost feels like new Ultegra 11-speed!

joejack951

Similar thread posted here recently and the answer was basically the same, a dirty front derailleur. It doesn't take much grit inside of a tightly wound, square wire torsion spring to cause it to bind.

PatrickGSR94

I still think the worn cable guide was part of it. And my stupidity for not putting the cable back on correctly.