New Red crank info, must read! :)

Discuss light weight issues concerning road bikes & parts.
Post Reply
thisisatest
Shop Owner
Posts: 1980
Joined: Sat Jun 13, 2009 4:02 am
Location: NoVA/DC

by thisisatest

156mm is what sram quotes for their mountain double cranks.

CamW
Posts: 206
Joined: Mon Jan 17, 2011 10:26 pm
Location: New Zealand

by CamW

This SRAM Doc ( http://www.sram.com/sites/default/files ... _rev_b.pdf" onclick="window.open(this.href);return false; ) states 145mm for the q factor which fits with the measured 146mm.

jooo
Posts: 1510
Joined: Wed Feb 02, 2011 3:48 am

by jooo

@thisisatest - not all XX cranks are 156mm. There are 3 versions, 156mm, 164mm and 166mm...

thisisatest
Shop Owner
Posts: 1980
Joined: Sat Jun 13, 2009 4:02 am
Location: NoVA/DC

by thisisatest

Yea- i was going to mention that, decided to not confuse the issue. Never heard of the 166 model though- was it made for one particular company's chubby bike with some junk in the trunk?

Boralb
Posts: 113
Joined: Sat Aug 22, 2009 11:44 pm

by Boralb

pdlpsher1 wrote:I just put the new Red cranks on my bike today. The old FC-R700 came off (762 g.) and the Red went on (576g.).


Is your crank 50/34 compact version? I've seen 53/39 standart on scale as 607g...

jooo
Posts: 1510
Joined: Wed Feb 02, 2011 3:48 am

by jooo

@thisisatest - I saw the measurements on the SRAM website a while ago. Memory is a bit hazy but have a feeling the 164/166 difference was GXP vs. BB30/PF30 or something like that :noidea:

tonytourist
Posts: 1186
Joined: Sat Oct 10, 2009 7:13 am
Location: 93306

by tonytourist

I run a 166 GXP on my mtb. They barely cleared on my old bike (08 Stumpjumper FSR) but there is plenty of clearance on my 2011 Stumpjumper FSR. My friend was rubbing his 156q arms on his SC Blur LTC :idea:
Last edited by tonytourist on Mon Jul 21, 2014 7:42 am, edited 1 time in total.

pdlpsher1
Posts: 1542
Joined: Thu Jul 19, 2012 6:09 pm
Location: CO

by pdlpsher1

Boralb wrote:
pdlpsher1 wrote:I just put the new Red cranks on my bike today. The old FC-R700 came off (762 g.) and the Red went on (576g.).


Is your crank 50/34 compact version? I've seen 53/39 standart on scale as 607g...


Mine is a compact GXP version. The BB30 compact should be even lighter (~520g. if I recall).

I could really feel the reduction in rotational weight (166g.) I love the new Red crank.

MikeMiranda
Posts: 70
Joined: Tue Nov 29, 2011 10:07 pm

by MikeMiranda

terzuya wrote:The Q factor on my exogram bb30 50-34 is 146 mm.



^ how does it shift with extralite rc2? And did you have to rotate the rings?

177
Posts: 7
Joined: Mon May 02, 2011 12:05 pm

by 177

Just received some compact bb30 cranks for the GF's bike.
Interestingly, they are within 40grams of my Vumaquads and would likely be lighter than without the super heavy chainrings.

Sram Red 2012 172.5 50-34
Image

VumaQuad 175 50-34
Image

timzcat
Posts: 315
Joined: Thu Sep 30, 2010 5:50 am

by timzcat

So the new Red is lighter then my Hollowgram SL cranks.
For 172.5 50/34 with Praxis rings I am at 543g

I am building a second bike and have been looking for another set of Hollowgrams and am having no luck. At this point I should probably try the new Red, my biggest issue being the increased Q-factor over Hollowgram.

pdlpsher1
Posts: 1542
Joined: Thu Jul 19, 2012 6:09 pm
Location: CO

by pdlpsher1

timzcat wrote:So the new Red is lighter then my Hollowgram SL cranks.
For 172.5 50/34 with Praxis rings I am at 543g

I am building a second bike and have been looking for another set of Hollowgrams and am having no luck. At this point I should probably try the new Red, my biggest issue being the increased Q-factor over Hollowgram.


By going with lighter rings on the Red you'll save an additional 50 g. This will put the Red at 472 g. which is very light. I have the GXP version of the new Red and I love it. I got it for less than $400 from a LBS.

Boralb
Posts: 113
Joined: Sat Aug 22, 2009 11:44 pm

by Boralb

And finally here is my compact gxp 172.5mm on scale.
92g savings over my 7900 duraace crankset :mrgreen:

Image

User avatar
Gearjunkie
Posts: 779
Joined: Tue Feb 19, 2008 5:17 am
Location: NZ

by Gearjunkie

Thanks Boralb - scale pic, nice :thumbup:

I wonder how much heavier for a standard 130BCD?

:?

GJ

MichaelB
Posts: 439
Joined: Tue Apr 22, 2008 4:31 am

by MichaelB

Boralb wrote:And finally here is my compact gxp 172.5mm on scale.
92g savings over my 7900 duraace crankset :mrgreen:



Can you please confirm which rings that is with please ?

Post Reply
  • Similar Topics
    Replies
    Views
    Last post