Front derailleur problem

[Spoked Wheels]

I started preparing my winter bike so I replaced the gear cables. I noticed that the old 105 triple 5603 derailleur, I think, H screw doesn't do anything. One can have it all the way out or all the way in and the outer plate does not move at all. I took the derailleur off and lubricated every area that I think needed lubricating and it moves better under load which is good but it doesn't help the H adjustment. The L screw works fine BTW.

It's still locked it the position that was originally so I can still use it (kind of) but I'd like to make a little adjustment to the outer plate.......

Any suggestions......?

 

[bpsmith]

Do you have your cable attached when doing the adjustment? If you have, then perhaps there is not enough tension?

The H Screw limits how far the derailleur travels past the big chainring. Obviously, this can only happen if there is sufficient tension to reach the point where the screw limits the travel.

 

[bpsmith]

This may help:

http://www.parktool.com/blog/repair-help/front-derailleur-adjustments

 

[Yellow Saddle]

I started preparing my winter bike so I replaced the gear cables. I noticed that the old 105 triple 5603 derailleur, I think, H screw doesn't do anything. One can have it all the way out or all the way in and the outer plate does not move at all. I took the derailleur off and lubricated every area that I think needed lubricating and it moves better under load which is good but it doesn't help the H adjustment. The L screw works fine BTW.

It's still locked it the position that was originally so I can still use it (kind of) but I'd like to make a little adjustment to the outer plate.......

Any suggestions......?

The H screw will just move up and down in fresh air when the derailer is in the L position. Ditto for the L screw when the derailer is in the H position. In other words, the derailer has to be installed and cable tensioned enough to change gears, when fiddling with those screws.

Further, it is such a simple device that even a novice will figure it out if they just look at it and fiddle a bit. Your answer is right in front of you somewhere, you'll figure it out.

 

[Spoked Wheels]

The H screw will just move up and down in fresh air when the derailer is in the L position. Ditto for the L screw when the derailer is in the H position. In other words, the derailer has to be installed and cable tensioned enough to change gears, when fiddling with those screws.

Further, it is such a simple device that even a novice will figure it out if they just look at it and fiddle a bit. Your answer is right in front of you somewhere, you'll figure it out.

Thanks for the post.

Mmm not sure what I have to figure out...... I have the chain on the largest chainring and the smallest cassette sprocket and the chain just touches the outer plate of the FD. I tried to undo the screw a little and ended up with the screw all the way out and the plate didn't move at all..... down to the middle and up again and chain still touching the plate just a little, so I changed down to the middle ring to test if screwing the H screw all the way in made it worse..... so chain up to the largest ring again and it's not worse.... still in the same position..... I was expecting the chain not be able to go up or at least be harder but not.
The tension is spot on, it changes up and down without hesitation.

The L and H screws must be touching something inside that makes the plate move..... unlikely but if the material was plastic then it's possible that the screw made a whole so when I turn the screw all the way in nothing happens.

Anyway.... it's not a big problem cause I hardly use that combination on that bike..... 11T sprocket and 52T chainring..... the good thing is that the chain wont drop off the big chainring

 

[Tim Hall]

That sounds like the cable tension needs increasing, as the travel of the FD from small to big ring is governed by how hard you pull the cable. As the H screw isn't affecting the travel, it suggests the cable can't pull it enough to (a) hit the screw and (b) move the FD over enough to clear the chain when it's on the small sprocket. Tighten the cable a tadge by unscrewing the the barrel adjuster a quarter of a turn. I'd also look at the alignment of the mech, to make sure it's parallel with the chain rings.

 

[lpretro1]

If a bike has been left for a long time and if it was put away dirty/wet then the FD can just seize up - the corrosion gets to all the little pivots. Might be new fd time

 

[andytheflyer]

^^^ what TH said. There's no magic here. When you shift to a bigger ring it's only the cable tension that controls how far the FD moves, the tighter the cable, the more the movement - up to a point. If the H screw does not stop the mech pushing the chain off the big ring then the shifter may do just that. If the cable tension is too tight and the FD moves up to the H stop the shifter will be really stiff - too stiff - something may break.

Provided that nothings broken or stripped, take the H screw out, clean it, run it in and out of the hole a couple of times and lube it with Copaslip or similar so it won't seize up. Back it right off and then play with the cable tension to satisfy yourself that the shifter can indeed dump the chain off the big ring. Then it's only a matter of setting the H screw to limit the travel and getting the cable tension just right. It wants to be just tight, and only just, when on the small ring. If it's bar tight on the small ring it's too tight.

There's not much to these - have a play so that you understand how it works - no magic here! And keep it clean and serviced!

 

[bpsmith]

Did I not say the tension is too low, in the first reply? Just saying...

 

[themosquitoking]

Did I not say the tension is too low, in the first reply? Just saying...

Looks like everyone agrees with you


OP, have you checked the cable tension is correct?

 

[Spoked Wheels]

That sounds like the cable tension needs increasing, as the travel of the FD from small to big ring is governed by how hard you pull the cable. As the H screw isn't affecting the travel, it suggests the cable can't pull it enough to (a) hit the screw and (b) move the FD over enough to clear the chain when it's on the small sprocket. Tighten the cable a tadge by unscrewing the the barrel adjuster a quarter of a turn. I'd also look at the alignment of the mech, to make sure it's parallel with the chain rings.

Actually, I did increase the cable tension and then I drooping to the middle and granny ring wasn't as good. a bit of hesitation which I definitely don't need......

But it's all sorted now.... nothing that I did other than taking the bike for a ride. All I remember is that I was shifting up and down and then I climbed a hill and on the way down I selected 11 - 52 and it was fine.... no chain rubbing anymore

My thanks for all the replies.