Front derailleur adjustment? Chain won't shift down.

[JamesTaylor02]

Hello everyone,

I've just got back from my commute and I've noticed that the chain won't shift down to the smallest ring on my compact chain ring. The bike is a Cube Peloton.

The chain seems to want to stay in the biggest ring and won't move. The front derailleur does move, but the chain does not, causing the chain to scrape along the derailleur when it is positioned for the smallest ring.

I've had a very brief play with the high - low screws but they haven't really made anything change drastically enough to make me investigate further.

I'm tempted to take it to the LBS but don't really want to if it's something I can do myself? Any help will be gratefully received.

James.

 

[uclown2002]

Need to loosen off the cable a touch. If you have a down tube barrel adjuster, turn it clockwise a little until it drops.

 

[bpsmith]

High and Low screws literally only set the Highest and Lowest point that the chain can go. They have no impact on shifting gear. above advice is spot on in respect of getting it sorted. Could also be a dry cable if that doesn't work.

 

[raleighnut]

Dry cable or sticky mech, although we did have someone earlier with a snapped spring.

 

[mrandmrspoves]

If the high low settings were working correctly they are unlikely to have come out of adjustment. Move the front gear shifter to the position to move the front derailleur onto the smallest chain ring. Now rotate the crank as if pedaling....If in this position the cable is slack but the mech doesn't move the chain onto the small ring, try manually pushing the derailleur over to move the chain. If this works, the derailleur is sticking and may have grit or rust stopping it moving all the way over. A good clean and lube and repeated up and down should slacken it off so it works again. (This assumes that the Low stop screw is not too far in and restricting inward movement)
If on the other hand the cable does not slacken and the derailleur doesn't move inwards, this would indicate a binding gear cable. To confirm this, disconnect the gear cable and if the cable is the fault, the derailleur will move inwards to move the chain onto the smallest chain ring. If this is the case, don't bother cleaning and lubing the cable - just replace it, because they are a cheap item that should be regarded as a consumable, and trying to revive the old cable will almost certainly lead to continued problems.

 

[JamesTaylor02]

Thank you for your replies, I'll have a proper look the weekend!

 

[Mike_P]

Had the same problem ever since the front derailleur fixing screw worked loose. Although it worked fine one afternoon in the heatwave it has played up ever since. Anyway after an hour of getting no where with it this afternoon I suddenly noticed what the problem was, during that heatwave my cheap Sports Direct bottle cage had broken and I had replace it that evening with one from Halfords - that was the cause of the problem as it was just bearing on the mechanism and stopping the cage from moving its full extent.

 

[raleighnut]

Had the same problem ever since the front derailleur fixing screw worked loose. Although it worked fine one afternoon in the heatwave it has played up ever since. Anyway after an hour of getting no where with it this afternoon I suddenly noticed what the problem was, during that heatwave my cheap Sports Direct bottle cage had broken and I had replace it that evening with one from Halfords - that was the cause of the problem as it was just bearing on the mechanism and stopping the cage from moving its full extent.

HALFORDS