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Discussion Starter · #1 ·
So i just installed a new to me shimano 6600 crankset to replace another set I had. I'm using this with shimano 5500 (105) brifters, frt and rear deraileurs. Spent some time setting up the shifing, and it seem that when i'm in the small chainring, and in a lower gear (12, 13, 14) on the casette, the chain is rubbing the inside of the large chainring. Its not rubbing the frnt. der, its definately the big chainring... once i shift a bit and get to the 4th gear on the casette, the rubbing goes away... cant seem to adjust anything to keep it from rubbing...

question, i noticed on the install instruction from PARK, it discussed small spacers that were supposed to be used in some instances (i didn't have any), would these help, was i supposed to use a spacer on the BB, or is there something else. Thanks all in advance!
 

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Road bikes are not really designed to allow you to ride them in the highest rear gears with the lowest front. You don't need to, it's a duplicated gear combination.

However, you may have a chainline issue if it rubs even in the 14. Check it by reading this:
http://www.sheldonbrown.com/chainline.html

The spacers Park mentions are usually to make 73mm BBs work in 68mm frames. A better question is: Which BB are you using, and is it the correct size for this crank?
 

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Rub it............
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The 6600 BB is an external bearing BB. So there is no size. Since the BB shell is probably 68mm, no spacers are required. When running the small ring up front and the smallest 2-3 gears on the cassette, rubbing on the big chainring can occur. Some bikes do it, some don't. It really depends on the size of the chain ring - a compact 50 won't rub as much - and the length of the chain stays due to the size of the bike.

A smaller bike will have more rub than one that is of larger size.

Your options are this. If needing to ride in the highest gears (smallest) when in the small chainring, your going to have to double shift. Shift the front to the large chain ring, and shift up a gear or two in the rear till you find the gear that you need.
 

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Discussion Starter · #4 ·
Sounds good... i dont plan on being in those gears anyways... just didn't have that with my old crank.. i pretty much stay in my large chainring except on steep hills when i'll downshift, but i'm in a much higher gear on the casette... just wanted to make sure there wasn't something i was missing on the install...

it is a 68mm shell by the way, so i think i'm all set...
 

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thats a 10 speed crank and 9speed chain which can make this problem worse than usual
 

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BikeFixer said:
thats a 10 speed crank and 9speed chain which can make this problem worse than usual
There's no difference between 9 and 10 speed cranks.

I ride small bikes, and none of mine rub until the last cog.
 

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rx-79g said:
There's no difference between 9 and 10 speed cranks.

I ride small bikes, and none of mine rub until the last cog.
Maybe no difference in some 9 and 10 speed cranks but there is a difference in many 9/10 speed and 10 speed chainrings. I had the same chainrub problem on a crankset that had FSA 9/10 speed 50/34 chainrings where the chain would 'clip' the pickup pins on the big ring when I was in the little ring and the last two small cogs. A change to Shimano compact chainrings cured that problem.
 

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rx-79g said:
There's no difference between 9 and 10 speed cranks.

I ride small bikes, and none of mine rub until the last cog.
Actually YES there is :thumbsup:
 
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