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Old 02-09-08, 08:39 AM   #1
Versa2nr
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Did I break it already?

Hey all,

I have currently employed my 03 Hardrock as my day to day commuter and have run into a problem. I have an older XT crankset that has served me for many years flawlessly. But here is the problem. I recently replaced the front derailleur with a Deore since the alivio that I had was dying a horrible death. Now when I am running the middle ring in front I run into an issue when I am in the smallest 2 rings and the largest 2 rings on the cassette. I have the most annoying rub on the inside and outside of the cages. It almost seems like the travel of the chain up and down the rear cassette is too wide a movement for that derailleur. I cant romp on the cranks when I am sprinting otherwise my chain rubs on the the outer part of the derailleur cage and drops down to the smaller ring. It is so frustrating that I am about to convert it to a 1x9. Is this a derailleur issue or a bottom bracket issue I am sick of spending nights trying to adjust this front derailleur.

Thanks
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Old 02-09-08, 08:58 AM   #2
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Is the BB loose?Can you wiggle the crank at all?Sounds like something is flexing.Maybe try opening up the spacing of the front derailleur.Physically bend it open a bit more.Might give you the space you need.
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Old 02-09-08, 09:38 AM   #3
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no nothing moves but I do notice that when I am standing and pedaling that it is a more pronounced rubbing. I wonder if there is a derailleur that has a wider cage on it? I had already taken it to the bike shop and they cant find anything wrong with it. Maybe I am too fat for these cranks?? 6'4" and 250 lbs???
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Old 02-09-08, 09:56 AM   #4
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Quote:
Originally Posted by raleighrider75 View Post
Is the BB loose?Can you wiggle the crank at all?Sounds like something is flexing.Maybe try opening up the spacing of the front derailleur.Physically bend it open a bit more.Might give you the space you need.
i agree with physically spreading it but when you compare the two, if you still have the old alivio, check to see how much wider if at all the cage is. if desperation sets in that bad you could get a friction or one of those clicky friction shifters but that is a pain in the arse to deal with but it would work.
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Old 02-09-08, 10:05 AM   #5
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http://www.parktool.com/repair/readhowto.asp?id=75
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Old 02-09-08, 10:24 AM   #6
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I already followed the Park tool site recommendations on the adjustment. Still no dice. Its like the travel on the rear cassette is too much. Gotta love the disclaimer on the bottom of the page about exceeding the specifications of the manufacturer....
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Old 02-09-08, 10:28 AM   #7
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Yes tou could be heavy, I have the same issue but am shorter 5'10 240, the causes are varied but most common is the design of the overall gearing, you should not be useng the extreme ranges in any of the front chain rings.

In general

Outer Ring = 1st position thru 5th on most systems
Middle ring = 3rd position thru perhaps you can get the second to last but hardly ever the last .
Inner Ring = 4th thru last.
Sheldon's gear chart will allow you to work out the progressions for your specific drivetrain,but no your bike is never going to "work" in every/ any gear combination.
You should "never" respace the front deralieur with the minor exception of after a crash,somebody worked really hard on the Physics and it should work right if set up and used properly.
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Old 02-09-08, 10:37 AM   #8
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Sorry did I see that you had an OLD alivio like a 7 speed and you put a New deore 9 speed spaced ft der on?
If so theres yer prob.
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Old 02-09-08, 12:31 PM   #9
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well the derailleur that I just took off was original to the bike which came standard with the 9 speed drivetrain. everything is set up with the 9 speed in mind. rear der is an XT however I do have a dura ace 9 speed rear cassette. Not sure if that would make an issue. I just prefer a road casette on my commuter. I will probably take it apart again this coming week during my day off.
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Old 02-10-08, 11:35 AM   #10
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Before you get drastic, pull the FD completely and reinstall it according to Park's instructions. Don't just adjust it. I often find this is the only way I can troubleshoot triple FDs.

That said, you could have some play in your BB or a flexy BB shell, causing more extreme rubbing when mashing.
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