Front derailleur problem

[langobee]

Hi,

I have recently installed a new gear cable as the old one had frayed. I took the opportunity to start from scratch and learn a bit about my bike.

I had adjusted the front derailleur so that it is about 1mm from the largest front chain ring and lined it parallel with the frame. I adjusted the low limit screw so it has a small gap between the derailleur and chain. I then connected the new cable while pulling it taut.

When i shift up it shifts fine onto the middle front chain ring but then jams the chain when trying to shift up to the largest ring. I have tried to adjust the height of the derailleur but not joy.

Any ideas guys? Really don't want to take it to a shop as don't want to be beaten!!!!!

Thanks in advance

[cyclerUK]

Have you also adjusted the "Hi" limit screw to make sure the derailleur moves far enough outwards over the big ring?
Also you could try adjusting the cable if there is too much slack.

[langobee]

(06-16-2010, 10:36 AM)cyclerUK Wrote:  Have you also adjusted the "Hi" limit screw to make sure the derailleur moves far enough outwards over the big ring?
Also you could try adjusting the cable if there is too much slack.

Thanks.

I think the high limit screw is ok as the derailleur seems to want to push past the chain but just jams it between the middle ring . Also the cable seems pretty tight.

Could the far left of my derailleur be too close to the chain ring? (Obviously keeping the far right about 1mm from the top)

[cyclerUK]

If it was O.K. before the new cable then I would suspect that the dérailleur is a fraction to low if you lowered it. Try lifting it a 1mm to give a 2mm gap.
You say you adjusted the dérailleur to run parallel to the frame?
It should be parallel to the chainrings if it already isn't.