Setting up middlebu...
 

[Closed] Setting up middleburn duo cranks

 Bazz
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I may be putting some middleburn duo cranks on one of my bikes next year, now i set these up on my mates bike and although it was working i wasn't entirely happy with the set up. I was using a standard 3 speed front shifter and when i've done this in the past with a 3 ring crankset with the outer removed just setting the hi/lo stops has worked out. With the middleburn though this doesn't seem to work quite as well.

Any pointers please?


 
Posted : 23/12/2011 10:46 pm
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I would index the outer duo ring with position 2 on the shifter so the tension is removed when I drop to the inner ring.
Use the front mech outboard limit screw to prevent it going further outboard if you press the shifter again.
Use the front mech inboard limit screw for the inner ring.

Merry Christmas from PaulD


 
Posted : 23/12/2011 10:51 pm
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What Paul said.


 
Posted : 23/12/2011 11:19 pm
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Agree with the above, when I tried to treat the duo rings as middle and big my three speed shifter didn't have enough throw. Setting as if small and middle has been fine, just use the upper limit as advised.


 
Posted : 23/12/2011 11:31 pm
 Bazz
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Mmm.. thanks for the replies, what is said above is what i tried, however when the limit screw were set the shifter still went all three clicks, with the middle one neither going from small to big or big to small, you had to in affect shift twice for each change.

Shimano XT mech and shifter btw in case it makes a difference.


 
Posted : 23/12/2011 11:51 pm
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Ah, I'm using old X9 shifters and a shimano XT front mech. I bet different combinations do make a difference.


 
Posted : 23/12/2011 11:58 pm
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A lot of double set ups prove difficult with standard triple mechs. You never seem to get a decent shift.


 
Posted : 24/12/2011 12:24 am
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I go with what bill boy said, u never get it totally right!
But I would set it up the other way and set the mech up on the inner ring, then put the shifter into the 2nd click (middle) and then clamp the cable to the mech.
I find doing it this way you can adjust the cable via the barrel a bit better than the other way and if you do use the granny shift on the shifter all you get is slack cable and one click that doesn't do anything. so no fear of shifting over the outer ring.


 
Posted : 24/12/2011 12:51 am
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^^ Paul's method works for me ^^


 
Posted : 24/12/2011 9:21 am
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Hmmm, fair points - I use Gripshift which doesn't have indexing.


 
Posted : 24/12/2011 11:09 am
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I do the total oposite to paul:

chainrings in "middle" and "inner" positions. limit screws set for both top and bottom... 3 speed shifter;
"outer" position shifts to ring in "middle" posn, "middle" to "inner" ring and shifters "inner" posn just des nowt mech hits limit screw and cable goes slack... works fine.

I did try the other way and found I did on occasion try to "overshift" do it often enough and you just stretch and bugger the cable...

Last pair if gripshift I had were indexed. How old are yours?


 
Posted : 24/12/2011 2:02 pm
 69er
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Ive got Duo/ Sram XO shifters/ XTR mech set up. I've found using middle ring position on the shifter for the 29t (inner), and big ring position for the 44t (big) ring gives absolutely fautless performance.


 
Posted : 24/12/2011 2:14 pm
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What I mean is the front mech Gripshift just has clicks - so you just wind it to where you want rather pushing paddles to a certain position.


 
Posted : 24/12/2011 2:57 pm
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I have X0 Gripshift running a double front. I use the inner for the inner and position 2 for the 'outer'. This works ideally.


 
Posted : 24/12/2011 3:07 pm