Originally Posted by
wrk101
I think you misunderstood the advice. Leave the cable attached to your derailleur. Then pull the cable manually, find a spot where it is exposed, like on the downtube. From the highest gear (smallest cog), you should be able to manually pull the cable enough to reach all of the gears while moving the pedals (a bike stand works best for this, or have a friend raise the rear wheel into the air for you). If it doesn't reach the biggest cog, then either something is bent or your low limit is stopping you. Loosen the low limit a lot, and see if you can reach it. Remember to readjust the low limit before you ride the bike, so you do not risk throwing the chain and derailleur into the wheel and either crashing, or doing serious damage to the bike, or both.
Take close up pics and post if you want someone to guess whether something is bent.
Ah, I had misinterpreteted the OP's response and hadn't caught that he was simply retensioning the cable. Good catch.
OP: Once you check for full movement across the cogs by pulling by hand, as other posters said, loosen up the low limit screw and try again.
Additionally, on Apex RD's, if you stand behind the bike and look directly at the largest cog, try ( somewhat gently ) to move the RD so that the it is directly under the large cog. Check to ensure that the large cog, and the two pulleys ( gears ) on the RD are *exactly* lined up. That should give you perfect shifting into the large cog.
As a further sanity check - I presume you're not hearing any grinding when you try to move to the largest gear? If so, check and make sure that the upper pulley is not striking the large cog. If it is, you need to back off the 'B' adjustment screw so that there is a 6MM gap between the pulley and the cog.
And that makes me think - are you absolutely positive that you're using the low limit screw ( i.e, the upper one on the side of the derailler ) and not the B screw ( the one that comes out of the back of the RD )?