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Lightest 83mm cranks?

kidwoo

kidwoo

Artisanal Tweet Curator
Aug 25, 2003
42,149
13,358
Squirtin ketchup n' mustard on charred flesh
toodles said:
In one case the end of the crank arm was bent from the pedal insert out. The hole was basically 50% longer than original so I don't think it could be repaired. When the other one bent, udi stole the remaining good crank arm and used it to make a good set out of the surviving arm from a set he owned. Come to think of it, pretty sure he owes me beer for that....
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Damn you got all kinds of creative on those things.

screw the t bolt, get that beer!

Trade him a sandwich or something, that boy needs some meat!
 
C

-C-

Monkey
May 27, 2007
296
10
I like carbon, but for cranks on a DH bike? Not here at least.

Way too many stories about X0 cranks snapping. Yes you can rip a pedal out of a Saint, or similar, but how many snapped Saints have people seen? I think that's one place for me that's not for weight saving.

3 ride old bike:
 
D

dilzy

Monkey
Sep 7, 2008
567
1
Why would anyone seriously run anything but Saint on a DH bike? I run first gen Saint cranks on my Demo and apart from new BB bearings, they're perfect. Anything with ISIS is provably worse in the long run than the clamped spline interface shimano uses, that's just a fact.

I run SLX on my SX trail and they're as perfect as any product that I don't notice can be. Running uber light cranks just isn't advisable.

Seriously, Saint, don't even think about anything else.

As an aside, that XO crank, the aluminium insert is square at the back (if I'm correct in thinking the insert pulled out) which is totally pro, having a square edge running accross the axis of the crank, super engineering there broskis.
 
D

Deano

Monkey
Feb 14, 2011
233
0
i love all the new carbon cranks.. and the other light stuff coming.

everytime i try and convince myself to get new shiny stuff, i consider the price diff vs weight and performance.

and i stick to my saints.

i might have to get the NEW saints tho.. i cant really use the excuse i broke my old ones tho.

Saints have been setting the standard for a few years now, and looks like they will keep doing that.
 
mtg

mtg

Green with Envy
Sep 21, 2009
1,862
1,605
Denver, CO
Lelandjt said:
So the new Raceface SixC and Sram XO are the current lightest cranks?*
How much lighter are they than my old Gravity Lights?

*Not counting BBs and ignoring Clavicula.
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It appears that way.

I have a new set of the Gravity Lights made from the 7050 alloy, and they are about 840g w/ BB, but no ring, if that helps. But, the SIXC cranks are en route, and destined for my new frame I'm building up. If you want weights of any of the individual parts, let me know.

The X0 seems to be of questionable durability- I was riding right behind a guy that clipped a rock with his pedal, and the crank arm snapped right off. It wasn't that hard of a hit, either.

As far as interface on the Race Face, it is their EXI system, which appears to basically be a combination of X Type and ISIS. The BB is the same as X Type, but I think it has ISIS spines for the interface with the crank arm. I'll find out soon.
 
p-spec

p-spec

Turbo Monkey
May 2, 2004
1,278
1
quebec
theres a reason shimano hasn't bothered making carbon cranks for dh,xc,road

Who would want something flexing were your power transfer is.
 
Bikael Molton

Bikael Molton

goofy for life
Jun 9, 2003
4,088
1,235
El Lay
mtg said:
As far as interface on the Race Face, it is their EXI system, which appears to basically be a combination of X Type and ISIS. The BB is the same as X Type, but I think it has ISIS spines for the interface with the crank arm. I'll find out soon.
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Please let us know if that perpetually-loosening scenario is still happening with the RF.
 
Lelandjt

Lelandjt

adorbs
Apr 4, 2008
2,653
1,008
Breckenridge, CO/Lahaina,HI
p-spec said:
theres a reason shimano hasn't bothered making carbon cranks for dh,xc,road

Who would want something flexing were your power transfer is.
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Shimano made a carbon Dura-Ace crank. Shimano has the most sophisticated aluminum forging technology so they stick with what they're good at. Doesn't mean there aren't plenty of carbon cranks that are stiffer and lighter. Toughness is something that's still being sorted out so I'd say your previous history with cranks should dictate whether carbon is ready for you yet. I've never damaged a crank and I've been using the same pair of "weak" Gravity Lights for 4 years so the only thing holding me back is cost.
 
William42

William42

fork ways
Jul 31, 2007
4,029
789
ilfreerider said:
Shimano also doesn't use sealed bearing in their hubs, so would you say its the way to go ?
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their hubs also feel really good, last a long time, and are incredibly easy to repack.

There is more the one way to skin a cat.
 
I

ilfreerider

Monkey
Oct 3, 2003
268
1
israel
from my experience they are heavy, the engagment is poor and they need constant attention when riding hard or in poor conditions.i guess there is a reason why they are the only (high end) manufacturer using it.
 
William42

William42

fork ways
Jul 31, 2007
4,029
789
ilfreerider said:
from my experience they are heavy, the engagment is poor and they need constant attention when riding hard or in poor conditions.i guess there is a reason why they are the only (high end) manufacturer using it.
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no idea what the climate is like in israel, where I am I don't see a lot of slop - even when it rains its not super mucky. I also work at a shop, and don't mind spending 5 minutes pulling my wheel off, opening my hubs, dropping grease and new bearings in, and putting everything back together.

and that said, I'm currently running sealed bearing hubs.

edit: anyway, back ot
 
Dogboy

Dogboy

Turbo Monkey
Apr 12, 2004
3,221
646
Durham, NC
ilfreerider said:
from my experience they are heavy, the engagment is poor and they need constant attention when riding hard or in poor conditions.i guess there is a reason why they are the only (high end) manufacturer using it.
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Engagement is better than Hope and DT Swiss (both fine hubs) as well as others. Weight is competitive with all but the lightest hubs. Need constant attention? Nope.
 
no skid marks

no skid marks

Monkey
Jan 15, 2006
2,511
29
ACT Australia
Are. Ranks really the right place for carbon? Due to size restrictions can carbon cranks actually be made lighter while still being at least as tough? Carbon bars and seats seems like a bad idea due to their diameter not meeting the carbons needs for a larger box section to maximize strength. Yes there's no clamping force issues with cranks like bars and stem, but they still. Red pedal inserts and bb connecting and also they need to be kept thin for q factor etc.
 
4130biker

4130biker

PM me about Tantrum Cycles!
May 24, 2007
3,884
450
I'm sold on my carbon cranks and am a bit surprised at all the people breaking them. The point about how hard you are on cranks in the past is a good one- I've never had issues in the past with cranks that some would say suck...
 
mtg

mtg

Green with Envy
Sep 21, 2009
1,862
1,605
Denver, CO
no skid marks said:
....Due to size restrictions can carbon cranks actually be made lighter while still being at least as tough? Carbon bars and seats seems like a bad idea due to their diameter not meeting the carbons needs for a larger box section to maximize strength...
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Using composites allows for an anisotropic structure vs isotropic; combining that with high stiffness and strength along the direction of the fibers, that's where the structural advantage of carbon lies. Make it strong where you need it, and light elsewhere. It's not increasing cross-sectional area; that's what you do when you switch to lower strength, but lower density materials (i.e. steel to aluminum).

Anisotropic: not the same strength in all directions (eg. composites using unidirectional tapes or woven fabric, not the randomly oriented chopped fiber stuff)
Isotropic: same strength in all directions (eg. metals)
 
jonKranked

jonKranked

Detective Dookie
Nov 10, 2005
89,422
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media blackout
ilfreerider said:
Shimano also doesn't use sealed bearing in their hubs, so would you say its the way to go ?
Click to expand...
William42 said:
their hubs also feel really good, last a long time, and are incredibly easy to repack.

There is more the one way to skin a cat.
Click to expand...
ilfreerider said:
from my experience they are heavy, the engagment is poor and they need constant attention when riding hard or in poor conditions.i guess there is a reason why they are the only (high end) manufacturer using it.
Click to expand...
to touch on what leland said, shimano is really effing good at forging/casting things. as much as i've always wondered about why they never switched to sealed bearings, i've never, ever, had major issues with a shimano hub.
 
no skid marks

no skid marks

Monkey
Jan 15, 2006
2,511
29
ACT Australia
mtg said:
Using composites allows for an anisotropic structure vs isotropic; combining that with high stiffness and strength along the direction of the fibers, that's where the structural advantage of carbon lies. Make it strong where you need it, and light elsewhere. It's not increasing cross-sectional area; that's what you do when you switch to lower strength, but lower density materials (i.e. steel to aluminum).

Anisotropic: not the same strength in all directions (eg. composites using unidirectional tapes or woven fabric, not the randomly oriented chopped fiber stuff)
Isotropic: same strength in all directions (eg. metals)
Click to expand...
I must admit my carbon knowledge is pretty limited, but surely the larger the diameter the more ease for carbon design. In the case of bars and stem, surely that's why we got 31.8 and now Easton are pushing 35mm. As for cranks with the limited space it doesn't appear a big enough surface area is available for bonding in the pedal threads or making the cranks both stiff, strong, tough, and light.
Wouldn't trying to build it light be much the same as low density metals, so stiffness etc can be gained by larger diameter. Also flatter surfaces would add to strength etc wouldn't it?
 
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