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1st time I tried... what did I do wrong ?
#1
1st time I tried to replace a rear derailleur...

I have a Trek 7200 that I bought used ( for $30!!! ), it came with SRAM Max Comp Shifters (7sp grip ) and a Shimano Acera Rear Derailleur. Not sure if these were the original units?

The bike had a pretty rusty handlebar and cables so I decided to replace them. Also I noticed when inspecting the bike that the front derailleur was so corroded it was amazing that it worked. so I decided to replace it as well. All went fine until I installed the new rear derailleur, (which I only replaced because it was cheap enough and I was paying for shipping for all the other stuff anyways...).
I can not get it to move across the gears to shift at all ! Any Ideas what I screwed up ?

Should I give up and reinstall the old one,,,which was working fine before I took it off ? I feel stupid, like IF IT AINT BROKE DON'T FIX IT !!!!!!!
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#2
Now I have replaced the old one and it is doing the same thing.. The derailleur does not move across the gears when I twist the shifter. The cable is tight enough. WTF did I do wrong installing thr derailleur ????
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#3
1st make sure that the derailleur will move without the cable by pushing it with your hand; it should spring back to the highest gear (smallest cog).

Next grab the end of the cable that was attached the derailleur, and pull with moderate force - about the same as was required to move the derailleur, and then shift between gears, the shifter should pull the cable as you downshift. It should be smooth between the clicks.

Re-read the instructions. http://techdocs.shimano.com/techdocs/index.jsp

make sure you have the cable routed in the correct place - this is an easy oops.

What kind of derailleur did you get? What did you have?

Note, you have a SRAM MRX shifter; not max
Nigel
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#4
(08-06-2011, 08:01 PM)nfmisso Wrote:  1st make sure that the derailleur will move without the cable by pushing it with your hand; it should spring back to the highest gear (smallest cog).

Next grab the end of the cable that was attached the derailleur, and pull with moderate force - about the same as was required to move the derailleur, and then shift between gears, the shifter should pull the cable as you downshift. It should be smooth between the clicks.

Re-read the instructions. http://techdocs.shimano.com/techdocs/index.jsp

make sure you have the cable routed in the correct place - this is an easy oops.

What kind of derailleur did you get? What did you have?

Note, you have a SRAM MRX shifter; not max

1st,, Yep did that , Next,,, when the cable is connected to the derailleur it only moves the pulley gears back and forth but not sideways across the gears.,,,

I don't have the exact model # next to me right now but the derailleurs are the same model.

roger the mrx not max...

Guess I'll just have to bite the bullet and take it to the shop....

Thanks anyhow..
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#5
(08-06-2011, 11:29 PM)kimi Wrote:  when the cable is connected to the derailleur it only moves the pulley gears back and forth but not sideways across the gears.,,,

I also think you must have the cable routed wrong. There's normally a cable housing stop with a barrel adjuster. The housing stops there and the inner wire goes through to clamp at a small mounting bolt. (But just guessing without a picture.
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#6
(08-07-2011, 10:29 AM)DaveM Wrote:  
(08-06-2011, 11:29 PM)kimi Wrote:  when the cable is connected to the derailleur it only moves the pulley gears back and forth but not sideways across the gears.,,,

I also think you must have the cable routed wrong. There's normally a cable housing stop with a barrel adjuster. The housing stops there and the inner wire goes through to clamp at a small mounting bolt. (But just guessing without a picture.

GOOD GUESS! I looked at it again this morning and the bottom cable sleeve was not placed into the stop on the frame. Once I put it where it belonged everything mystically began to work ! lol

The how to video did not include this minor but important detail.

Thank you to both of you for your time.
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