Gears adjustment. Is LBS lying to me?
08-05-11, 09:33 AM
#1
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Gears adjustment. Is LBS lying to me?
OK. So I bought brand, shiny, new Trek 1.5. I opted for the compact crank as here in Netherlands there are no hills at all.
As soon as I started riding I noticed that I need 2 clicks of the shifter to switch from the big to the small chain ring in the front. In the shop they told me that this is normal, because the same shifters are used on the triple cranks and this is impossible to change. Is that correct? On the lever itself i clearly see "Tiagra Double".
My second question is regarding chain rubbing. I noticed that there is some chain rubbing in the front derailleur far from the chain cross gears. I.e. when the chain is on the big ring in the front the chain started rubbing in the 4 ring of the casette. Rings 5-9 are fine. I know that bigger ring in the back and bigger in the front should be avoided, but if i have to avoid half the casette it is a bit too much. Similar issue with the small ring in front, it starts rubbing after 5th ring in the rear to 9th.
I brought the bike back to the shop for tuning, they said everything is flawless now, but the issues persist. So basically, is it true that on compact crank it is normal to use 2 clicks to shift gears in the front and is it normal for the chain to rub in to the front derailleur when it is only slightly crossed?
As soon as I started riding I noticed that I need 2 clicks of the shifter to switch from the big to the small chain ring in the front. In the shop they told me that this is normal, because the same shifters are used on the triple cranks and this is impossible to change. Is that correct? On the lever itself i clearly see "Tiagra Double".
My second question is regarding chain rubbing. I noticed that there is some chain rubbing in the front derailleur far from the chain cross gears. I.e. when the chain is on the big ring in the front the chain started rubbing in the 4 ring of the casette. Rings 5-9 are fine. I know that bigger ring in the back and bigger in the front should be avoided, but if i have to avoid half the casette it is a bit too much. Similar issue with the small ring in front, it starts rubbing after 5th ring in the rear to 9th.
I brought the bike back to the shop for tuning, they said everything is flawless now, but the issues persist. So basically, is it true that on compact crank it is normal to use 2 clicks to shift gears in the front and is it normal for the chain to rub in to the front derailleur when it is only slightly crossed?
08-05-11, 09:38 AM
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The shifter has intermediate clicks that allow you to "trim" or fine-tune the position of the front derailleur cage to eliminate chain rub on the cage. That may be the extra click you're noticing. It's a feature, not a bug 
but it isn't there to shift a triple, so the LBS came up with the wrong explanation for its presence.
Anyway, use the trim clicks to solve your chain-rub problem.
but it isn't there to shift a triple, so the LBS came up with the wrong explanation for its presence.Anyway, use the trim clicks to solve your chain-rub problem.
08-05-11, 09:16 PM
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Sounds like a shoddy shop, not knowing the difference between a double and a triple shifter, and consequently failing to get yours set up properly.
The trim click should allow you to use 6 or 7 of your 9 without rubbing.
The trim click should allow you to use 6 or 7 of your 9 without rubbing.
__________________
Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list
Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list
