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Probably shouldn't have or didn't need to, but I started jacking with my front derailleur. Bottom line, I'm now at square one.

I have an e.thirteen bash guard, so the original thought was to lower the derailleur so that the outer cage just clears the top of the guard (36T). I don't want to, however, have the rear swingarm nail the derailleur at full travel. So, the first question...

1) When in the smallest chainring (and most likely the smallest cog), does your chain rest on the flat portion at the rear of the derailleur cage?

I'm not convinced that the derailleur can be lowered to the point where it doesn't rest on the flat portion, yet the swingarm clears that same portion of the cage. Thoughts?

John
 

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savechief said:
Probably shouldn't have or didn't need to, but I started jacking with my front derailleur. Bottom line, I'm now at square one.

I have an e.thirteen bash guard, so the original thought was to lower the derailleur so that the outer cage just clears the top of the guard (36T). I don't want to, however, have the rear swingarm nail the derailleur at full travel. So, the first question...

1) When in the smallest chainring (and most likely the smallest cog), does your chain rest on the flat portion at the rear of the derailleur cage?

I'm not convinced that the derailleur can be lowered to the point where it doesn't rest on the flat portion, yet the swingarm clears that same portion of the cage. Thoughts?

John
There is really only one optimal position (height) for the FD to function precisely. A new Shimano FD comes with the little see-through tag that you are supposed to use to set the clearance over the teeth of the big chainring. When set per this guide the FD works at its best for all three rings.

If you then remove the big ring and replace it with a bash guard, you do not change the height of the FD. It is still optimally positioned for the small and middle ring. You simply adjust the hi limit screw so that the FD does not respond to the attempt to shift onto the big ring, and becomes essentially a two position derailleur.

If you ever had the FD postioned correctly, go back to where it was originally positioned. Usually there is a nice "dirt tatoo" left on the seat tube showing exactly where is used to be.

John W.
 

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Arf, he said.
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savechief said:
Probably shouldn't have or didn't need to, but I started jacking with my front derailleur. Bottom line, I'm now at square one.

I have an e.thirteen bash guard, so the original thought was to lower the derailleur so that the outer cage just clears the top of the guard (36T). I don't want to, however, have the rear swingarm nail the derailleur at full travel. So, the first question...

1) When in the smallest chainring (and most likely the smallest cog), does your chain rest on the flat portion at the rear of the derailleur cage?

I'm not convinced that the derailleur can be lowered to the point where it doesn't rest on the flat portion, yet the swingarm clears that same portion of the cage. Thoughts?

John
Don't be concerned if the chain rests on the flat lip of the FD when the bike is on a stand. Don't forget that when you sit on the bike, all the angles change due to the rear suspension pre-load. Check if the chain hits the FD lip while you ride it. If it's properly adjusted it shouldn't.
 

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No, that's not phonetic
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If you can't see the dirt tatoo Papajohn mentioned, the safest and most accurate way to get the f der positioned is to quickly mount a 42 tooth outer ring, and set things up as if you were going to run it. This is going to save you a lot of guessing and trouble.
 
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