Front derailleur not shifting UP.

Caiser
Caiser Posts: 9
edited March 2011 in Workshop
Hi, I'm having some problems with my new bike.

The bike is less than two weeks old and has done less than 100 miles. When i first got the bike from the warehouse the front derailleur wasn't set up properly and shifting with it just didn't work. I managed to fix it up no problem and it worked fine for a few days. Then my brand new chain snapped... I complained and got a new one sent out straight away. The new chain was slightly longer than the previous chain so I took a few links out, it's currently 110 links long. Since I've put the new chain on the front derailleur wont shift up to the big ring. I've made all the adjustments correctly and adjusted it from the ground up. The strange thing is that it shifts fine when pedalling with my hands and under no resistance. As soon as i start pedalling with my feet or put any resistance on the pedals it just refuses to shift up, instead the chain grinds against the inside of the front derailleur.

I'm at a loss here, i've tried everything. I've looked on other forums and people have suggested chain suck, but the whole chainset is brand new and hardly riden. Any help or words of wisdom from you guys would be much appreciated.

Thanks.

Comments

  • sungod
    sungod Posts: 16,878
    if the fd can't get the chain onto the big ring, and it's correctly aligned, then there might not be enough cable tension, or maybe something is bent/broken

    if the various bits are shimano, go to http://techdocs.shimano.com and read the instructions on chain length and fd adjustment (although, if you've already done this, no point)

    but tbh if it's a new bike, take it back and demand they sort it out, it should not be badly out of adjustment when brand new
    my bike - faster than god's and twice as shiny