Front derailleur fu: ditch my mechanic?

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Hi Lee,
I have a 2006 Stumpjumper FSR Comp. I love the bike ‘cept for one thing: the Deore LX front Derailleur will not drop into the granny ring under a load (my 175lb load…) The mechanics at my LBS tell me it is tuned perfectly, but all they are doing is riding around the parking lot where of course it works fine. Nothing is worse than railing a nice turn into a steep climb, trying to drop the chain…please, puh-lease, ohhh Gawd Puh-leeeease drop, only to have it stick in the middle ring. Find a different mechanic or ditch it for XT or SRAM?
Michael

Hey Michael,

When you apply your awesome power, the bottom half of your chain is loose, but the top half gets super tight. Make sense?

Because your rear derailleur adjusts the bottom/loose half of your chain, shifting the rear under load is no big deal (not since about 1990). But since your front derailleur is trying to nudge the top/tight half of your chain, shifting the front under load is a huge deal. Especially if you’re 175 pounds of pedalling fury. The solution here is about 15% equipment/85% technique. OK, maybe 5/95.

Equipment – A higher end derailleur (XT, X.9, XTR) uses a stronger return spring than your LX. It’ll do a better job of coaxing your chain onto your small ring.

Technique – Learn to shift without chain tension.

Entering a corner:

1. Anticipate the gear you need for the corner exit.

2. Downshift and soft pedal into the right gear (BEFORE you enter the turn).

3. Brake if needed.

4. Rail the corner.

5. Hammer outta there (in the right gear)

Climbing:

1. Pedal, pedal, pedal.

2. Anticipate when you’ll need the small ring. Shift BEFORE you need it!

3. Give it a very hard pedal stroke.

4. Back off and make your shift. You shift at the “loose” moment.

5. Pedal, pedal, pedal.

If your mechanic is an experienced rider, he probably backs off automatically. Keep him and your money. Anticipate those downshifts!

— Lee

6 replies
  2. Michael says:

    Thanks Lee – Anticipating shifting makes sense. Being somewhere on the low end of the skills scale I have found myself trying to unsuccessfully shift, stall, slightly panic when I cannot immediately get my feet out of the pedals, and feel like Wily E. Coyote after he has just gone over the edge of a cliff. This will help. Hope you do a skills clinic in the central Sierra Foothills sometime.

  4. Peter S says:

    Single speed sounds like a great fix. Not for you? Get a pair of pliers and bend the derailleur cage (toward the small ring) where it contacts the chain during the middle to small shift. Bend a little at first, then some more, until you get the shift you want. You may have to adjust the big ring (outer) stop if it takes a large adjustment. Bend it with a wrench, hit it with a hammer, do whatever it takes to make it work, it’s just a bike.
    Good luck!

  6. John I says:

    Excellent advice about shifting before you need to. I’m sure someone out there is saying, “yeah but if I shift early then I’ll lose my momentum before I hit the bottom of the hill”.

    When you shift down into granny, shift up into a higher (smaller cog) in back. Then when you really need to grunt it out, just shift the rear back to the easiest gear. As it was mentioned above, you can shift down in back more easily than in front.

    John

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