double vs. triple rear derailleur

I am setting up a road bike from old parts and it will have a double crankset at first. But I might
want to experiment with a triple down the road.

I need to buy a new rear derailleur for the bike.

Is there any serious performance difference between a 'double' (Shimano's SS?) and 'triple'
(Shimano's GS?) rear derailleur when used on a double setup? I'm looking at the Shimano 105 or
Ultegra level.

(I know that I will need different front derailleurs and different chain lengths; using bar end
shifters so front indexing isn't an issue.)

Thanks.

> Is there any serious performance difference between a 'double' (Shimano's SS?) and 'triple'
> (Shimano's GS?) rear derailleur when used on a double setup? I'm looking at the Shimano 105 or
> Ultegra level.

If you think you might either go to a triple down the road *or* a wider-range rear cassette (toss an
11-32 mtn bike cassette on, for example), the triple rear derailleur makes sense. In theory it might
not shift quite as quickly, although I haven't found that to be an issue... and, of course it might
weigh an ounce more.

--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com

"Dan Daniel" <ddandaniel@pacbell.net> wrote in message
news:e4b4svsmgtdfkjdimttt90ph2p69th4hdo@4ax.com...
> I am setting up a road bike from old parts and it will have a double crankset at first. But I
> might want to experiment with a triple down the road.
>
> I need to buy a new rear derailleur for the bike.
>
> Is there any serious performance difference between a 'double' (Shimano's SS?) and 'triple'
> (Shimano's GS?) rear derailleur when used on a double setup? I'm looking at the Shimano 105 or
> Ultegra level.
>
> (I know that I will need different front derailleurs and different chain lengths; using bar end
> shifters so front indexing isn't an issue.)
>
> Thanks.

Dan Daniel wrote:

> I am setting up a road bike from old parts and it will have a double crankset at first. But I
> might want to experiment with a triple down the road.
>
> I need to buy a new rear derailleur for the bike.
>
> Is there any serious performance difference between a 'double' (Shimano's SS?) and 'triple'
> (Shimano's GS?) rear derailleur when used on a double setup?

No. The only difference is 2 grams (Ultegra) or 4 grams (105)

I'm looking at the Shimano 105 or Ultegra level.
>
> (I know that I will need different front derailleurs and different chain lengths;

Actually, you don't need different chain lengths.

Sheldon "Like The Spam Sez, Length Is Good" Brown
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dddandaniel-<< I am setting up a road bike from old parts and it will have a double crankset at
first. But I might want to experiment with a triple down the road.
>><BR><BR>
<< Is there any serious performance difference between a 'double' (Shimano's SS?) and 'triple'
(Shimano's GS?) rear derailleur when used on a double setup? I'm looking at the Shimano 105 or
Ultegra level. >><BR><BR>

Nope, get the long cage......

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"