|Dura Ace front mech/ Ultegra Triple crankset problem.||goat29|
May 20, 2002 4:46 AM
|I'm building up a largely Ultegra Triple Group equipped bike but I went for the Dura Ace triple front mech cause my LBS didn't have the 31.8 clamp Ultegra unit and I figured what the hell, no compatibility issues, right?
Well, here is the thing, the DA triple crankset has a 53/39/30 combo while the Ultegra crankset has a 52/42/30. When I tried to set up the DA front mech in the usual way, the inside trailing edge of the mech hits the 42 chainring when shifting to the 52. So I moved the mech up the seat tube far enough so there is clearance over the 42, but now the mech is moved back relative to the BB cable guide so far that the cable rubs off the lower part of the mech below the cable fixing bolt!
Anyone seen this before? Am I missing something obvious? Should I just swap for the Ultegra?
I always thought these groupos were interchangeable.
|re: Dura Ace front mech/ Ultegra Triple crankset problem.||davet|
May 20, 2002 5:03 AM
|I am given to understand that the Dura-Ace triple front derailluers are NOT compatible with anything else. You will have to use Ultegra or 105.|
|re: Dura Ace front mech/ Ultegra Triple crankset problem.||grzy|
May 20, 2002 8:22 AM
|It's fairly important (critical in your case due to the cable issue) that the front der. cage arc match the crank. You see this a lot in the MTB world between XTR front der. and non-XTR crank/chainrings due to the standard vs. compact sizing. Usually you can get away with it, but it sounds like you have a cable lead problem and your only relief is going to be to get the correct der. You really want the advised 1 mm of vertical spacing above the large CR. Also, the DA triple front shifter does not work the same as the Ultegra and the Ultegra cage has a special shape. Triples are more sensitive to setup so you will be better off sticking to one group - mixing nad matching components will never be optimal.|
|DA triple der is 14 tooth (53-39) Ultegra is 10 tooth (52-42)||snuggleman308|
Jul 3, 2002 4:42 PM
|This makes all the difference in the world. Unfortunately, I've spent hours, days, weeks, staring at my drivetrain while spinning it on the workstand.
For example, inside the Ultegra cage there are numbs that fit (any) 10 tooth difference. Now I'm using 48-38-28.