Lightweight RD carbon fibre rear derailleur

Discuss light weight issues concerning road bikes & parts.
Ole
Posts: 212
Joined: Wed Jan 12, 2005 6:29 pm
Location: Oslo, Norway

by Ole

I replaced the stock pulleys on my Red RD with Extralite, and it brought the weight down to 138g. After replacing the Ti cable clamping bolt with alu, it was 137g.


Ole.

by Weenie


dynaserve
Posts: 272
Joined: Fri Jul 18, 2008 8:25 pm
Location: UK

by dynaserve

rward325 wrote:It's a slow day at the office:

RD Carbon Fiber 120g $1149.90 $9.52 per gram
Red 153g $299.99 $1.60 per gram
Record 187g $279.99 $1.49 per gram
DA 180g $159.99 $0.89 per gram

I know there is a price to pay for weight savings and I can live with that. But I think I just found my limit.


Seen the date of the post... But surely rward325 logic is not correct. Taking ultegra as benchmark the $/gram saving would be:
Ultegra 210
RD Carbon 120 1149.9 $12.8
Red 153 299.99 $5.3
Record 187 279.99 $12.2
DA 180 159.99 $5.3
Interestingly DA & Red identical and Record as much as a rip off as Lightweight!!! :D

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Szczuldo
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Joined: Tue Aug 12, 2008 2:22 pm
Location: Salt Lake City, UT

by Szczuldo

dynaserve wrote:
rward325 wrote:It's a slow day at the office:

RD Carbon Fiber 120g $1149.90 $9.52 per gram
Red 153g $299.99 $1.60 per gram
Record 187g $279.99 $1.49 per gram
DA 180g $159.99 $0.89 per gram

I know there is a price to pay for weight savings and I can live with that. But I think I just found my limit.


Seen the date of the post... But surely rward325 logic is not correct. Taking ultegra as benchmark the $/gram saving would be:
Ultegra 210
RD Carbon 120 1149.9 $12.8
Red 153 299.99 $5.3
Record 187 279.99 $12.2
DA 180 159.99 $5.3
Interestingly DA & Red identical and Record as much as a rip off as Lightweight!!! :D


Your logic is also flawed since you have to take into consideration the cost difference as well, not only the weight difference. If people gave out free Ultegra I'd be ok with that though.

Ultegra...............210......109.99
RD Carbon........-90......+1039.91........$11.55
Red..................-57......+190.00.........$3.33
Record..............-23......+170.............$7.39
DA...................-30.......+50..............$1.67

Being unable to use tab instead of a ton of spaces or in this case periods in these posts is quite frustrating...

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coloclimber
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by coloclimber

Image
I haven't even touched the cable tension bolt yet. ~6-8 grams.

Red RD- ebay $220 (minus 25% cash back with live search)= $165
dark_albert pulleys and plate- $100= $265 for a 128 gram RD

Thats $2.01/gr compared to LWs $1039/gr
-Deacon Doctor Colorado Slim

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coloclimber
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by coloclimber

Image
Image
-Deacon Doctor Colorado Slim

109er
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Location: Oklahoma City

by 109er

shite thats good...
green jacket, gold jacket...who gives a sh*t


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djconnel
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by djconnel

Szczuldo wrote:Your logic is also flawed since you have to take into consideration the cost difference as well, not only the weight difference. If people gave out free Ultegra I'd be ok with that though.

Ultegra...............210......109.99
RD Carbon........-90......+1039.91........$11.55
Red..................-57......+190.00.........$3.33
Record..............-23......+170.............$7.39
DA...................-30.......+50..............$1.67

Being unable to use tab instead of a ton of spaces or in this case periods in these posts is quite frustrating...


Your logic is flawed because $/gram should be relative to the next cheaper/lighter option, not versus Ultegra. For example, given two derailleurs, one $10 more and 5 grams heavier, the second would be a terrible choice, even if relative to Ultegra it was a similar $/gram difference, because it's incremental $/gram is negative.

That said, relative to Red, the LW becomes $25.76/gram. Outrageous? I agree, but within a factor of two the number you get from the Trek Madone Black->Red series upgrade, which is popular. (Pez says there's a quality difference in this upgrade, as well, however)

Tillquist
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Joined: Fri Dec 30, 2005 3:33 pm
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by Tillquist

Principia wrote:Image

LW RD introduction :wink:


Very nice looking, maybe my Impulse need one :D
See all my bike h e r e

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Tubes6al4v
Posts: 225
Joined: Sat Feb 24, 2007 5:45 pm

by Tubes6al4v


:shock: .... :lol:

Holiday
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Joined: Thu Jul 24, 2008 12:50 am
Location: FAR EAST
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by Holiday

I got 1 for my DA Gruppo about a year+ ago and the shifting is way
to sensitive. Needed to fine tune after every long ride. It looks
great but would prefer the great to come with effieciency also, its now
sitting in a box.

Apparently the new ones are Campy and Shm compatible now but I
don't think they'll work with DA 7900 or Campy 11 spd.
Attachments
LightWeight Rr D.jpg
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BmanX
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Joined: Thu Nov 10, 2005 5:31 pm

by BmanX

coloclimber wrote:Image
I haven't even touched the cable tension bolt yet. ~6-8 grams.

Red RD- ebay $220 (minus 25% cash back with live search)= $165
dark_albert pulleys and plate- $100= $265 for a 128 gram RD

Thats $2.01/gr compared to LWs $1039/gr


I have to agree that I think the SRAM RED is the best for the money option if you can get one for just over $200 like I have done.

All I have done with my SRAM RED is put on a pair of Fibre-Lite pulleys and the weight went from 145g stock down to 131g but I also changed out the stock pinch bolt to a black anodized that was still a bit lighter.

I have to agree with Colo that if I can get the cable tension bolt sorted out that I could get this down to about 120 if I sorted this out and picked up a Dark Albert inner plate. I will see if Fibre-Lyte have a carbon outer plate for Red yet as I have some other parts on order from them.
BIG DADDY B FLOW
AERO & LIGHT is RIGHT

Cervelo SLC 5960g/13.13 lbs

BmanX
Posts: 3844
Joined: Thu Nov 10, 2005 5:31 pm

by BmanX

Does anytong on here have a good suggestion on how to eliminate the rear derailleur cable tension bolt as Sram has made it a beast to tune. I have heard that you have to drill and tap it too a bigger bolt then you can drill and tap that to use a lighter aluminum bolt but is there a better way of doing this :?:

Cheers.
BIG DADDY B FLOW
AERO & LIGHT is RIGHT

Cervelo SLC 5960g/13.13 lbs

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HammerTime2
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Location: Wherever there's a mountain beckoning to be climbed

by HammerTime2

Regarding LW RD, Holiday wrote:Needed to fine tune after every long ride. It looks
great but would prefer the great to come with effieciency also, its now
sitting in a box.
Hey, what do you expect for 750 euros? Picky, picky. :roll:

Principia
Posts: 226
Joined: Sat Jun 25, 2005 11:16 am
Location: Germany
Contact:

by Principia

tuned version from s.roth
http://www.light-bikes.de/website/new/2 ... t-rd-tuned

Image

Dura Ace 7800 black ultralight - 107.3g! ;)
http://www.light-bikes.de/website/new/2 ... ultralight

Image

Campa Record black 119.6g

Image
Light- Bikes news for weightweenies | Light-Bikes on twitter

by Weenie


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