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Discussion Starter · #1 ·
I recently had my derailleurs adjusted by my LBS after trying to mess with them a bit and failing miserably. I noticed yesterday that there is still some chain rub on 2 gears. The rub occurs (it's a triple 9 speed) when the front derailleur is in the middle ring and the rear is either in the largest or smallest rings. Are there any minor adjustments I can make to fix this or should I take it back into the LBS and make 'em fix it?
 

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Someone can correct me if I'm wrong (and I'm sure they will!) but in my experience with a tripple, (have 2 bikes with tripples) this is going to happen when I insist on staying in one gear up front when I should shift up or down to avoid the cross chaining.

For example when in the middle ring up front, and you hear the rubbing in either 1 or 2, you should shift down to the smaller ring up front, and shift the rear derailer up a gear or two (or more) to find the comfortable cadence you desire.

When in the middle ring up front, and you hear the rubbing in a high gear in the back (7, 8, 9? depends on how many cogs you have in the back) you should shift up to the big ring up front, and the rear derailer down to a smaller gear till you are comfortable.

If I'm wrong, I'll be in line behind you at the bike shop, becuase I sure would like to have free use off all my rear cogs while in the middle ring.
 

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'brifter' is f'ing stupid
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exactly right, you should be able to run the large cog/middle ring, but not the small cog middle ring. the 'half-click' in the shifter should make this possible.

and tripple is beer, triple refers to drivetrain parts :D
 

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Discussion Starter · #5 ·
Aaah, okay, that's good to know. I thought cross-chaining only applied to large/small and small/large; I thought the middle cog had free reign on all the rings. Though I recall the large cog rubbing, I rarely use the gear, so I may be mistaken.

Thanks much.
 

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I am running a Campy Veloce triple front, 9 spd veloce rear on my Bianchi. I have absolutely no rub on the rings, cage or cogs in any gear regardless of cross-chaining. I have full use of all 27 gears with no rub.
 

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Some info on trimming ("half-clicks")

Pehaps you can run all cogs from the middle ring, but as cxwrench said, you probably have to do some so-called trimming ( those "half-clicks" he mentioned). Trimming is moving the shift lever just enough to move the derailleur cage away from the rubbing chain a millimeter or two, but not so much as to push the chain onto the adjacent chainwheel. Here's an example instruction sheet for Shimano 105.
http://techdocs.shimano.com/media/t...01/SI-6SW0A-001-ENG_v1_m56577569830670796.pdf
 

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Discussion Starter · #8 ·
Sorry to drag up an old post. I seem to still be having the problem on the middle cog / small chainring. I can't seem to get the trimming feature to work, so I've been avoiding the smaller cog all together (I only ever shift into it when I'm removing my back wheel). Are there any other minor adjustments I could make?
 
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