Bicycle Mechanics - Crank Arms Help how to

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View Full Version : Crank Arms Help how to


nismosr
11-19-07, 08:27 PM
Below is my crank - is there a special tool I need to pull the crank ?

http://img.photobucket.com/albums/v444/nismosr/crank.jpg


vasracer
11-19-07, 08:30 PM
http://www.parktool.com/repair/readhowto.asp?id=122#shimano

No tools just loosen all the bolts and uses a little bit of force. the website above explains it better

nismosr
11-19-07, 08:48 PM
Thank got it .. now what kind of adjustment do I need to do on my FD ? I just replaced my crank with the FSA Compact installed already but its not shifting to the big ring..


vasracer
11-19-07, 08:51 PM
Was your crank a regular 53/39?

nismosr
11-19-07, 08:55 PM
THank got it ..

I just installed an FSA Compact crankset ... how do I adjust the FD - it's not shifting to the big ring and I need to shorten the chain also.

nismosr
11-19-07, 09:01 PM
52/39 was my regular front new one is 50/34 and cassette is 12-27. How much should I take out on the chain ?

vasracer
11-19-07, 09:06 PM
I believe you might have a problem with your FD because it is meant for a normal crank. The curvature of your FD might not be compatible with the smaller diameter chainring. Usually when we change out cranks to compacts we recommend changing the FD to a compact compatible FD. If not we gently bend the FD down slightly just to better match the profile of a smaller chainring. Then it's a matter of adjusting with the set screws.

As for chain length it's something that you have to judge because every set up is different.

nismosr
11-19-07, 09:14 PM
really ? Does Shimano makes a special FD for compact cranks ? I've seen new bikes with the same 105 FD just like on my bike with FSA Compact Crank.

vasracer
11-19-07, 09:19 PM
Shimano FD are made to work with compact and normal cranksets. If you have a Shimano 105, ultegra, or Dura-Ace you should be a good and then it's just a matter of adjusting the position. If it's a braze on (which i assume it is) lower the FD until it is about 2mm from the chainring teeth. This should give the FD the ability to pull the chain up onto the large chainring.

nismosr
11-19-07, 09:46 PM
Hey Vas thank you I did some adjustment this if my first time doing it .. finally figure out the High Low screw. now its shifting perfect. below is the new crank - did I set the FD just about right or too low ?

http://img.photobucket.com/albums/v444/nismosr/crank2.jpg

http://img.photobucket.com/albums/v444/nismosr/crank1.jpg

operator
11-19-07, 09:57 PM
http://www.parktool.com/repair/readhowto.asp?id=75

vasracer
11-19-07, 10:09 PM
If it's shifting right leave it where it is. Thats a nice crank hope you enjoy it.

nismosr
11-19-07, 10:17 PM
Thanks vasracer for the Help - Thank You - I've replaced my 105 crank to this FSA SL-K Compact Crank.
One more - when I'm on the 34 and 27 the chain is touching FD cage. now how do I adjust that so the cage would move back a bit.

vasracer
11-19-07, 10:22 PM
The low adjustment screw, loosen it slightly and you will see the FD move back. Adjust it with the chain in the position so you don't over adjust

nismosr
11-19-07, 11:11 PM
Just did works perfect .. now I need to shorten the length of the chain - whats the rule of thumb in doing this ? big cog big chain ring ? or smallest cog and small chain ring ?

operator
11-20-07, 06:31 AM
http://www.parktool.com/repair/readhowto.asp?id=26

nitropowered
11-20-07, 06:35 AM
I generally put it in small/small and take out enough so the chain doesnt rub on the bottom of the pully cage.

nismosr
11-20-07, 09:38 AM
I will try that .. now I need to get me a chain breaker ..