Bicycle Mechanics - FD change on a Trek 7.3 FX

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jgjulio
10-17-09, 07:51 AM
I am changing the gearing on my 2009 Trek 7.3 FX.

http://www.trekbikes.com/us/en/bikes/bike_path/fx/73fx/

It started with: Shimano EF60 trigger, 8 speed, Shimano M191 Front Dérailleur, Deore Rear Dérailleur.
I have changed the shifters to: Shimano Deore LX SLM580Sram PG970 Cassette (11-34) - Shifters, Sram PC971 Chain (9 speed), and I am trying to install and adjust a Shimano FD M510 Front Dérailleur.

http://www.universalcycles.com/shopping/product_details.php?id=6902&category=71

Here is where my problem is. Either I am doing it wrong or the part is the wrong part for this bike.
I read on the Shimano website that this is a top swing (pull) FD but I also read on other sites that these can be either top or bottom pull. The Trek is a bottom pull FD setup.

Question: 1. What is the correct FD for this bike?
2. Do I have the wrong part?

Thanks

blasternot112
10-17-09, 09:28 AM
elaborate on the problem please
desertdork
10-17-09, 10:44 AM
Your M510 FD may be used with "top-pull" or "bottom-pull" cable routing. When your cable is routed through the pulley on the back of the seat tube, you'd use the bottom-pull routing. Some people may suggest just bypassing the pulley and using the top-pull routing to avoid the lower pulley altogether. The correct routing is in the directions that should have been included with your FD.

omdemarseille
10-18-09, 11:42 AM
Did you replace your crankset? If it is still the original 8 speed setup, there might be issues with the new 9 speed system, as the chain is thinner and spacing different.
JiveTurkey
10-19-09, 01:03 AM
I read on the Shimano website that this is a top swing (pull) FD but I also read on other sites that these can be either top or bottom pull. The Trek is a bottom pull FD setup.

Question: 1. What is the correct FD for this bike?
2. Do I have the wrong part?

Thanks

Short answer: You are using the correct part, so what exactly is giving you trouble?

Have you installed a FD before? FDs are much more finicky than RDs. Follow these directions: http://parktool.com/repair/readhowto.asp?id=75

Byt he way, "swing" and "pull" are not the same thing. Pull is where the cable is coming from. Swing refers to where the FD's body is in relation to the pivot; the current and new FDs' bodies swing above the pivot, so they are top-swing.
jgjulio
10-20-09, 06:25 AM
OK problem solved. I went to my local Bike Station and the very nice mechanic adjusted the FD in about three minutes. I watched and theoretically I was doing what he did but his adjustment worked great.
I really don't get what I was doing wrong but nevertheless my bike now shifts fine.
joejack951
10-20-09, 06:37 AM
Did you replace your crankset? If it is still the original 8 speed setup, there might be issues with the new 9 speed system, as the chain is thinner and spacing different.

The chain is thinner but the chainring spacing is the same. He won't have any issues using the 9 speed chain on an "8 speed" crankset.
jgjulio
10-20-09, 07:15 AM
Yep the "8 speed" chainring spacing did not cause any problems.