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Discussion Starter · #1 ·
i have been working on my xc bike recently (new cassette, new cables, der. hanger, chain, etc.) as i haven't ridden in a long time due to a blown fork. it is equipped w/ 2004 xt dual control levers / shifters. however, for the rear (right side), i can't get the shifter to change gears.

as a test, should i be able to shift through the gears without having the cable inserted? it seems like i should be able to as it would rule out the cable not being properly seated. i have taken all of the covers off and screws out to see what is going on in there and it almost seems like it is seized up. on another note, it doesn't look like there is a specific place for the end of the cable to sit on the white resin / plastic piece (the part that has the groove for the cable to run through). maybe that is my problem.

thoughts?
 

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Yes with any indexed shifter.....

you should be able to run through the gears just working the lever both up and down. This is not an uncommon problem with shimano shifters. The factory lube becomes quite with a little dirt and dust added, and disuse, becomes quite sticky over time. What we do at the shop when we run into this problem is pretty simple. Remove all of the covers that you can without actually disassembling the shifter mechanism, you'd never get it back together right if you did. Now you have two choices, either douse the mechanisim with degreaser and use an old tooth brush and scrub it out, carefully. Then if you have compressed air blow it dry then relube everything heavily with something like Triflow or other light oil. Or just douse it with Triflow (and I mean get it dripping). From there work the shifter until it frees up. What happens is, there are little spring loaded pawls that engage ratched cogs inside the shifter. When the lever is moved in one direction, usually the down shift, the pawl engages the ratchet and moves the cable by moving the cable seat. When moved the other way a pawl moves a lever that disengages the down shift pawl from the ratched cog and allows it to move one nothch before spring tension snaps the pawl back into place. This releases tension on the cable. This is highly over simplified as there are a couple of other items involved as well, but it's the general idea. So when the factory lube gets sticky and stiff, it prevents these pawls from engaging as they should. The springs that provide the tension on the pawls and other bits are quite small and not overly stiff. So when the lube gets sticky it prevents the springs from doing their job and the pawls can't move as they should. That's why you're not hearing any clicks when you shift, things aren't engaging properly. I know we've done several dozen bikes this season at the shop with the same problem, more than in the past. Likely because of the high gas prices. People are diggin out the 10 year old clunker that hasn't been ridden in 2 or 5 years and wanting to get it in shape to ride. So we've seen allot of them.

Anyway, a good cleaning/degreasing and a relube should solve your problem. Just one trick that I've learned that helps. Get a pice of old shift cable and cut it to about 4 feet long. Once you've cleaned and lubed the shifter, mount it back on the bar without the covers installed. Insert the cable in the seat as you would a new cable. Then wrap the cable around your hand once and run through the gears putting mild tension on the cable like your derailleur would. You'll be able to feel the shifter working and you'll be able to feel any sticky spots and you'll be able to feel any hesitation in engagement. If it feels crisp and positive though the range both up and down, you've done it right.

Good Dirt
 

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Discussion Starter · #3 ·
That's Exactly What I Need! One More Question

that's perfect. this bike has been sitting for about 1.5 years as my coilair is much more fun. now that i have a new fork and want to trade out the coilair for a covert or rune, i want to get this one back on dirt.

my next question, is there a specific place within the dual control mechanism, such as on one side of the white resin / plastic piece, where the end piece of the cable should sit? when i insert it into the shifter, should i be in the lowest or highest gear to ensure it sits correctly? i can't remember what the zinn book recommends.
 

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You should be in the...

highest gear when you insert cable. Unless it's a rapid rise system. You'll be able to figure it out once you have the shifter working. You want the cable seat as close as possible and as much inline with the outside opening as possible. And yes there is a place for the cable head to sit. Usually it's on one side of that white resin piece. It should have a hole through it. Just slide the cable though the hole toward the outside opening. The cable head will stop the cable when it's fully seated. The cable stop may or may not enclose the cable head when everything is in place. Just depends on how the cable stop was desigened.

Good Dirt
 
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