New Red crank info, must read! :)

Discuss light weight issues concerning road bikes & parts.
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Juanmoretime
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by Juanmoretime

So with a ceramic bottom bracket ( regular bottom bracket as in 68mm threaded) and a ring transplant you could have a sub 600 gram crank and bb combination?

Also does anyone know what the q-angle is on the new Red?

CBRE We would all still like to know what modification had to be made to the ring to make it work? :beerchug:
RESIDENT GRUMPY OLD MAN.

by Weenie


CBRE
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by CBRE

Juanmoretime wrote:So with a ceramic bottom bracket ( regular bottom bracket as in 68mm threaded) and a ring transplant you could have a sub 600 gram crank and bb combination?

Also does anyone know what the q-angle is on the new Red?

CBRE We would all still like to know what modification had to be made to the ring to make it work? :beerchug:



Simple, remove catch pin on big ring, unbolt old rings and install Paxis rings, 10 minute job, 50 grams less.
Curt Brown

2016 Cannondale EVO Etap 13.8#'s
2012 Cannondale Supersix EVO etap 13.7#'s
2017 Cannondale SUPER X Force 16.0#'s
2016 Cannondale FatCad2 28.1#'s
2011 Cannondale Carbon Flash 1 17.9#'s

alexalecu
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by alexalecu

CBRE wrote:Simple, remove catch pin on big ring, unbolt old rings and install Paxis rings, 10 minute job, 50 grams less.


Does that mean that any standard 5 bolt rings will work on the new Sram Red crankset? Speaking of which, which BCD is yours?
One more question: how did you position the shifting ramps?

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prendrefeu
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by prendrefeu

^^^^^ Yes.
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CBRE
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by CBRE

alexalecu wrote:
CBRE wrote:Simple, remove catch pin on big ring, unbolt old rings and install Paxis rings, 10 minute job, 50 grams less.


Does that mean that any standard 5 bolt rings will work on the new Sram Red crankset? Speaking of which, which BCD is yours?
One more question: how did you position the shifting ramps?



Yes, any 130bcd will work, mine are 180 out, works perfect, now about 1000 miles perfect shifting.
Curt Brown

2016 Cannondale EVO Etap 13.8#'s
2012 Cannondale Supersix EVO etap 13.7#'s
2017 Cannondale SUPER X Force 16.0#'s
2016 Cannondale FatCad2 28.1#'s
2011 Cannondale Carbon Flash 1 17.9#'s

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prendrefeu
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by prendrefeu

Just got in the GXP version of the crank, compact.
Initial weights revealed remarkably light arms & spindle, competitively light 34t ring (that was already known from SRAM), heavy-ass 50t (as CBRE hinted with his finding of the 52t) and overall great quality.

Rough calculations on some components that are still arriving, based from documented weights, indicate a total crankset weight of ~590g (including BB).
I'll set up a thread when I have everything in, with scale shots.
Exp001 || Other projects in the works.

durkonion
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by durkonion

Not any 5 bolt will work. The outer ring has to be the same thickness: 4mm. Otherwise you will get runout issues.

pdlpsher1
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by pdlpsher1

Bump. I'm looking to shed some weight from my current R700 compact cranks (760g. w/o BB). My understanding is that by going with the 2012 Red compact cranks I would see somewhere about 520g. w/o BB? Assuming the GXP press-fit BB weighs about the same as my current press-fit Shimano BB this would result a weight drop of 240g :shock: Please let me know if I'm in the right ball park. My crank is a 170mm.

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prendrefeu
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by prendrefeu

GXP Compact 172.5 (170 will be the same)
Arms (L+R+spindle) is ~ 402g
The 50T chainring from SRAM is rather heavy at 128g.
34T is 28g
Bolts are all aluminum, ~9g for the set

That should give you proper calculations, everything else you can look up.
If you play your cards right, you can go to ~580g complete (ready to ride including BB) without using CF chainrings.


GXP crankarms are heavier than the BB30 crankarms because the GXP uses a steel spindle. The BB30, being a larger diameter, allows for the use of alloy spindles. This results in a lower crankarm weight. I wasn't in the mood to change my frame though, and later on the GXP can be applied to other frames I have on hand, so I went with the GXP/BSA variety.
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pdlpsher1
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by pdlpsher1

prendrefeu,

Thank you for the speedy reply. So I added up the numbers and it looks like the complete crank minus the BB is 567g. That is more than 200g. lighter than my current crank 8) The price on the new Red crank is dropping and I can't see any other competition to the new Red crank in terms of value.

My future diet plan
BR-7700 to 2012 Red Aero Link 74g. savings
Ti spindle for my Speedplay X2 50g. savings

Total cost for the three changes is $700 for a total weight saving of 324g.

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prendrefeu
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by prendrefeu

Right on! :beerchug:
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Gearjunkie
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by Gearjunkie

Does anyone have weights for the GXP std, 53/39? Some good prices out there just now for the 2012 crank, so looking to see if it's worth upgrading from my old Red GXP std to 2012.

Thanks in advance

GJ

MikeMiranda
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by MikeMiranda

Will the praxis rings need to be rotated also on the 50/34 crank set?

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prendrefeu
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by prendrefeu

Yes.
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gospastic
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by gospastic

Gearjunkie wrote:Does anyone have weights for the GXP std, 53/39? Some good prices out there just now for the 2012 crank, so looking to see if it's worth upgrading from my old Red GXP std to 2012.

Thanks in advance

GJ


I think BikeRumor weighed them at 588g, excluding BB, not sure of the length though.

by Weenie


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