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Discussion Starter · #1 ·
Regarding performing a triple to double conversion. I'm in the process of ordering the BB and crankset. Is the Triple derailuer compatible? I'm assuming it is and it is merely a matter of resetting the stops but have no experience with this.

Thanks in advance,

TCN

PS. components are all ultegra 6600 with the exception of the crankset (DA 7700)
 

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Same cassette, same shifters? Should work

I don't see how the rear d is going to know whether there's a granny ring on there or not. Should work fine.
Just out of curiosity, though, why are you making the swap? That' s a fair amount of money to spend to make your bike less versatile. But maybe that's because I NEED a granny gear.
 

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Discussion Starter · #3 · (Edited)
Sorry, I should have specified... I'm refering to a triple front deraileur. It is the older version of the Ultegra triple (6603 I believe). I'm assuming the only difference between this and the double version is a longer throw to accomadate the greater distance it must travel. Thus setting the limits for a double should not have any effect but I wanted to ask given I've never done this.

As for you other question, the current long cage rear deraileur is being replaced with a spare short cage that I have on hand. It will be paired wiltha 12-25 cassette. As for making it less versatile. Hardly. I never use the triple which means I'm always in the two biggest chainrings. Because of the extremely screwed up chainline, it is very difficult to get the front deraileur adjusted such that it does not rub in the big ring. This means for me this setup is actually less functional than a double as I cannot use the entire gear range without an annoying rub. IMHO triples paired with a 130 mm rear hub are just plain bad ideas because of the extreme chainline they create relative to a 135 MTB hub (which just works better) and I'd just rather not deal with it.

Thanks for the reply and sorry for the confusion.
 

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Cory said:
I don't see how the rear d is going to know whether there's a granny ring on there or not. Should work fine.
It has more to do with the amount of chain the rear der can suck up. The long cage rear der's (the ones found on triple drivetrains) can eat up more chain than the short cage ones. Since a double has less chain, the short cage can suck up the extra chain (since it has less to worry about). However the short cage doesn't have enough to suck up the extra chain in the triple.

Putting the long cage on the double is less than ideal, but it will work.
 

· NeoRetroGrouch
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TCN said:
Sorry, I should have specified... I'm refering to a triple front deraileur. It is the older version of the Ultegra triple (6603 I believe). I'm assuming the only difference between this and the double version is a longer throw to accomadate the greater distance it must travel. Thus setting the limits for a double should not have any effect but I wanted to ask given I've never done this.

As for you other question, the current long cage rear deraileur is being replaced with a spare short cage that I have on hand. It will be paired wiltha 12-25 cassette. As for making it less versatile. Hardly. I never use the triple which means I'm always in the two biggest chainrings. Because of the extremely screwed up chainline, it is very difficult to get the front deraileur adjusted such that it does not rub in the big ring. This means for me this setup is actually less functional than a double as I cannot use the entire gear range without an annoying rub. IMHO triples paired with a 130 mm rear hub are just plain bad ideas because of the extreme chainline they create relative to a 135 MTB hub (which just works better) and I'd just rather not deal with it.

Thanks for the reply and sorry for the confusion.
The cage on the FDs are shaped differently for the double and triple. Whether it works to your satisfaction is up to you.

As far as the chain rubbing the big ring, since you are moving the two largest rings inward it will rub more.

TF
 

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Discussion Starter · #6 ·
I'm sorry, You lost me...

You're saying that moving the chainrings inward, more inline with the center of the cassette, with an improved chainline will make the chain rub the front deraileur more???

Seems to be counter intuitive.

Thanks for the information regarding the shape of the front deraileur.

TCN
 

· NeoRetroGrouch
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TCN said:
I'm sorry, You lost me...

You're saying that moving the chainrings inward, more inline with the center of the cassette, with an improved chainline will make the chain rub the front deraileur more???

Seems to be counter intuitive.

Thanks for the information regarding the shape of the front deraileur.

TCN
Sorry, I thought you said 'rubs the big ring', not 'rubs IN the big ring'.

But as far as rubbing the FD, that's just adjustment. I set mine so that I can run all the way across the cogs without rubbing using the two trim positions in the center ring. Then fine adjust the big and little ring to use all but the opposite extremes.

TF
 

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Discussion Starter · #8 · (Edited)
Thanks!

For some reason I've always found this very difficult to align properly. I've set it up essentially as you describe with but I can never get either the big ring or the granny aligned such that it doesn't rub on the front deraileur cage. It is possible that this is an issue regarding the positioning of the deraileur, but if it is I've never been able to nail it down. So I've set is up such that the middle ring runs rub-free and the big ring and the granny rubs only in the largest cog or smallest, respectively.

I've conceded this with the idea that if I'm using these cogs I should probably be in the next chainring anyway. I double checked the type of front deraileur, and it is a 6503 not the 6603 as I originally thought. I'm also noticing that the deraileur cage was significantly re-designed between the two. The 6503 looks much more like a double with the inner portion of the cage smaller and closer in alignment with the outer. I'm wondering if the redign wasn't a fix for the issues I have experienced.

Regardless it's a mute point now as I decided to suck it up and replace the deraileur. Picked up a DA 7700 for 44.00 at icycles.

Thanks again, I learned a bit from this.
 
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