# Front Derailleur woes



## jfd986 (Jul 17, 2011)

Front derailleur won't shift bicycle into the big chainring. I tried adjusting limit screw, didn't help.

Then I physically tugged on the bottom end of the derailleur and the chain shifted. Is the derailleur bent out of shape? What's the best way to fix this?


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## AndrwSwitch (May 28, 2009)

It's probably that your cable isn't installed correctly. On a contemporary drivetrain, I'd say it's an indexing problem. Since you don't have an indexed shifter, that's not it exactly. But, same diff.

Park Tool Co. » ParkTool Blog » Front Derailleur Adjustments

I highly recommend book marking Park Tool and reading their article on any subject before you start messing with it. At least for a while - this stuff does become more intuitive.


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## jfd986 (Jul 17, 2011)

Yeah I looked at the big blue book before I touched the limit screws. I guess I'll look again, and take a look at the website. The thing is, it would shift fine in the past, but NOW it doesn't shift. I think it may have been caused by me dropping the bike, just not sure what exactly is wrong and how exactly to rectify.


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## AndrwSwitch (May 28, 2009)

OK, well at least you looked at the book.

I highly doubt the limit screws have anything to do with the problem you're having.

Since it was previously working and it isn't now and you dropped the bike, I'd bet that has something to do with it. Does the derailleur line up nicely with the chain rings? If you damaged the cage, it probably won't anymore.

The thing about tugging on the derailleur still suggests a problem with the indexing, to me. So if you think the cage looks okay, set the lower limit screw correctly, reset the cable, and see if that takes care of it. The cable doesn't need to hang loose when the shifter is all the way in the low gear position - it just needs the tension off it. Then you won't run out of range of motion on it when you go to shift up.


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## cxwrench (Nov 9, 2004)

jfd986 said:


> Yeah I looked at the big blue book before I touched the limit screws. I guess I'll look again, and take a look at the website. The thing is, it would shift fine in the past, but NOW it doesn't shift. *I think it may have been caused by me dropping the bike*, just not sure what exactly is wrong and how exactly to rectify.


maybe hold it up to the computer so we can see, yeah? 

if you ask for help w/ problems like this, pictures can help us out a lot. how can anyone on an internet forum provide the correct answer to your question if we have never seen the bike?


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## jaegs (Jul 15, 2006)

Is the derailleur a clamp on? If so, it may have been knocked/twisted out of alignment. Happened to me and it looked like it was aligned, but didn't shift well.


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## jfd986 (Jul 17, 2011)

I solved this one by moving my front derailleur down a few mm so that it's vertically more properly aligned with the big ring. I can thank the big blue book for that one, look at the "Bent Chainring" thread for a discussion of my latest problem.


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## acidrane (Aug 13, 2011)

i don't think id want to touch derailleurs again! lol. i got my bike on tuesday and the FD wouldn't shift, like yours. i spent over an hour on it trying to adjust it. i read the shimano instructions, the park tools instructions, watched your tube videos. nothing. yesterday, i got a chance to take it to my lbs. best $8 ever spent (FD and RD)! lol i guess i don't have the hang of it yet.


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## PlatyPius (Feb 1, 2009)

jfd986 said:


> Front derailleur won't shift bicycle into the big chainring. I tried adjusting limit screw, didn't help.
> 
> Then I physically tugged on the bottom end of the derailleur and the chain shifted. Is the derailleur bent out of shape? What's the best way to fix this?


A. NEVER, EVER adjust the limit screws if you don't know what you're doing. The fact that you CAN move the derailleur to the proper position by hand, but still adjusted the screws, tells me that you don't.

B. If the derailleur will move to the big ring by hand, but won't with the shifter, what does that tell you?





Answer: the front derailleur/shift cable is too loose/has "stretched". Adjust as needed.


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## jfd986 (Jul 17, 2011)

acidrane said:


> i don't think id want to touch derailleurs again! lol. i got my bike on tuesday and the FD wouldn't shift, like yours. i spent over an hour on it trying to adjust it. i read the shimano instructions, the park tools instructions, watched your tube videos. nothing. yesterday, i got a chance to take it to my lbs. best $8 ever spent (FD and RD)! lol i guess i don't have the hang of it yet.


What was the problem with your derailleur?


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## acidrane (Aug 13, 2011)

as far as i saw, he made adjustments to the adjustment screws and the cable tension. both of which i played around with as well and couldn't get it to work properly.


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## Mike T. (Feb 3, 2004)

I fixed two non-shifting front derailers last year by re-aligning them. They had both been crashed on the right side and had swiveled slightly. Please don't *ever* touch limit screws (as Platy says also) unless you *know* what's stopping the der from shifting. Limit screws don't mysteriously turn themselves.

Pull the cable by hand (along the DT) and if it shifts then find the problem - slipped or swiveled der or cable length (some incorrectly call it cable tension). Hold the cable and operate the shifter. Does the cable move? The issue must be diagnosed before any fiddling happens. Most people fiddle with adjustments without having a clue as to what they're doing.


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## SFTifoso (Aug 17, 2011)

I have a feeling your cable might have stretched or come loose from the bolt that anchors it, and it has lost the necessary tension.


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## cxwrench (Nov 9, 2004)

SFTifoso said:


> I have a feeling your cable might have stretched or come loose from the bolt that anchors it, and it has lost the necessary tension.


just to be clear on this...cables do not stretch. housing compresses, ferrules get more fully seated on housing. these both give the end result of the cable being 'loose', but it's not because the cable actually 'stretched'.


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## Smokeydave (Sep 14, 2011)

cxwrench said:


> just to be clear on this...cables do not stretch. housing compresses, ferrules get more fully seated on housing. these both give the end result of the cable being 'loose', but it's not because the cable actually 'stretched'.



I didn't know this. I have heard stretched cable so many times I believed it. Thanks.


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