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Old 09-05-10, 09:39 AM   #1
bradtx
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600 8S RD brifter questions

Hi All, Last week I disassembled the 600 FD brifter and it's repaired and fine... at the moment. I then discovered that the RD brifter, which worked fine a few days ago had locked up!

Not wanting to go through another disassembly, not to mention the RD shifter is bound to have more teeny, springy parts I have used aerosol brake cleaner followed by LPS1 to unlock the shifter. It's still a bit ratchety, but I'll relube with LPS2 and see if it improves.

Now to what I'm not sure is a problem. With the shifter fully relaxed in the small cog position there's a small piece blocking the hole where the shifter cable goes. I can move it with a small allen head wrench to install a shifter cable, but is this indicative that something else inside is broken? I'd hate to install the brifter and have a failure just a few hours later!

TIA for any help,
Brad
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Old 09-05-10, 11:25 AM   #2
bikeman715
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it can be a sign something is broken, but if you run a cable thou it and shift it thou all your gears down to your lowest gear you should be able to see the cable get shorter. When you up shift you'll need to pull on the cable as the dérailleur would for it to move. After all of this and it does work yes it broken and need replacing. What does the piece look like ? can it be dirt ?
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Old 09-05-10, 07:25 PM   #3
bradtx
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bikeman715, I put it away for a few hours and then looked at it again with 'new eyes'. While I can get a cable to nestle properly, it's a real PIA to remove. It looks like something broke that is preventing the selector to fully home and that is preventing the downshift to index properly (8 to 7 is a bit premature). I can shift through all of the gears, but downshifting is unacceptably stiff (just not going to work with even an aggressive shove with my fingers) while upshifting is now normal.

I think it's just toasted, probably my fault since it isn't my primary bike it will sit for extended periods of time without being used.

Brad
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Old 09-05-10, 07:39 PM   #4
Fred Smedley
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Sounds like you still have grease gumming things up, Barnett says to partially disassemble, , separate shift mechanism from levers and use solvent and then compressed air. I like brake clean as it evaporates. You might need to do this several times to get all the old grease out. Tri- flow is working well on my shifters so far, again the solvent evaporates leaving lube.
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Old 09-06-10, 09:07 PM   #5
bradtx
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FS, I think that you're right, I just can't always get the shifter to go to the fully released position. When it is fully released lever travel is normal to the second position shift and all the way through to the eighth position (Shimano calls the most outward position number 1 and the innermost position number 8). If it isn't fully homed the shift to the second position is too early in the lever's travel and the shifter gets out of sequence and locks up at fifth or sixth position going inward, but it does work sometimes so there's still hope.

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