Shimano launches carbon crankset

Jeff Jones

News from Eurobike:

http://www.bikeradar.com/news/article/shimano-launches-carbon-dura-ace-crankset-12255

Interesting that they decided to keep an aluminium spider.

LangerDan

If I got some of that fake carbon fibre wrap from Halfords, I think I could probably do the same to my crankset . Still it probably saves 30-50g over the current set and puts a more fragile material on the outer surface, which is the important thing.

Probably just part of a new, improved carbon groupset with electronic shifiting option for 2009.

shockedsoshocked

Anyone else agree it looks better than the current DA cranks?

wildmoustache

no ... i think it's much less attractive than the current DA crankset which is a work of art.

DA does need to get lighter and this helps. still some way off Record and even heavier than chorus

maddog 2

now we just need a compact version.

cougie

I never saw the point of CF cranks. Looks like Shimano think similarly, but have to do it for fashion.

Garybee

I like the look of the aluminium alloy Dura Ace cranks personally, and i've got Campag on all my bikes.

pliptrot

Shimano have a huge investment in aluminium forging equipment, and can probably do things with aluminium that no-one else can. It does seem, therefore, that this is more a nod to fashion than a real step forward. Nonetheless, it does look quite attractive, and as Shimano spend more on R&D than Campag's total turnover we must infer that they consider it worthy.

APIII

I think they look nice. The weave is certainly better looking than Campag's.
Agree that from a funtional point of view, it's difficult to see what the improvement will be over the current version.

Rob Sallnow

APIII wrote:

I think they look nice. The weave is certainly better looking than Campag's.
Agree that from a funtional point of view, it's difficult to see what the improvement will be over the current version.

Campag carbon cranks don't have a weave as they use a form of carbon fibre better suited to the application. It looks like it has been chiselled from a lump of black marble and is a thing of beauty.

Shimano have gone for the fashionable bling looking unidirectional weave and that may explain why they can't get the required strength and stiffness and need an alloy frame inside it.

drenkrom

Not bad! I'd never shell out the required cash for them, but I'll gawk a few seconds the first time I see some out on the road. Then, I'll remember how much I don't like carbon crankarms and look somewhere else. I want the matching STI levers, though. When are those due?

giant_man

Ahh yes Shimano carbon cranks, only about 4 years behind Campagnolo. That's innovation for you! :roll:

kevin_stephens

not available in 165 so irrelevant. come to think of it, does anyone do 165mm carbon chainsets?

pliptrot

Do you think those of us who have Campag carbon cranks from BEFORE they made them from a more suitable material, i.e. with a woven design, can get our money back? Or did we pay handsomely to be Campag's guinea pigs? Certainly, judging by some comments on this forum, that would be OK, as it is evident that some folk think a dog turd -suitably embossed with the C word of course- would be a thing of beauty.

pliptrot

Do you think those of us who have Campag carbon cranks from BEFORE they made them from a more suitable material, i.e. with a woven design, can get our money back? Or did we pay handsomely to be Campag's guinea pigs? Certainly, judging by some comments on this forum, that would be OK, as it is evident that some folk think a dog turd -suitably embossed with the C word of course- would be a thing of beauty.

pliptrot

Gosh, I just can't get the forum to accept t*rd. Guess I'll have to use SRAM instead.

Smokin Joe

ShockedSoShocked wrote:

Anyone else agree it looks better than the current DA cranks?

A fresh dog turd covered in vomit looks better than the current DA chainset.

Rob Sallnow

giant mancp wrote:

Ahh yes Shimano carbon cranks, only about 4 years behind Campagnolo. That's innovation for you! :roll:

Campag carbon cranks first saw the light of day in 2002.
Back in those thankfully long gone days they were trying to emulate the distinctive look of their top of the range alloy crank by using unidirectional carbon fibre round an alloy insert....nobody would try that these days!!!

acorn_user

"Shimano spend more on R&D than Campag's total turnover we must infer that they consider it worthy."

Ouch, that's a lot of money! Pity it's not as elegant as the 9 speed cranks were.

Dorian Gray

wildmoustache wrote:

no ... i think it's much less attractive than the current DA crankset which is a work of art.

DA does need to get lighter and this helps. still some way off Record and even heavier than chorus

Agree that the aluminium Dura-Ace crank is rather special. It exudes purpose, and the form-follows-function appearance is somehow very satisfying from an engineering perspective. It's not elegant, perhaps, so it might not suit all bikes, but it certainly suits a racing bike. As for weight, doesn't Record weigh 692 grams (including the bottom bracket "overboard cups"), and Chorus 728 grams? The alloy Dura-Ace crankset is 740 grams, and this new half-carbon one is 709 grams. Seems like a decent advance to me.

cougie wrote:

I never saw the point of CF cranks. Looks like Shimano think similarly, but have to do it for fashion.

Cranksets are one of the heaviest bits of a bike, so if carbon reduces the weight there, which it seems to do, it very much makes sense!

Truthfully, I dislike this step by Shimano. The carbon looks like the bling bonnet of a boy-racer's Corsa: definitely a bit tacky compared to the Campy stuff that, as someone above said, looks like it was hewed from a solid block of marble. The knowledge that it's just carbon over aluminium doesn't help matters. Shimano are undeniable masters of aluminium, but it would seem that Campagnolo are streets ahead of them in carbon. Browsing through the new Campagnolo catalogue (PDF file) one cannot help but be impressed with the engineering innovation over the last couple of years. Skeleton brakes, Ultra-Torque cranks (with the Hirth joint), several kinds of carbon fibre, titanium and aluminium alloys, even cheap plastic composites where appropriate (Xenon levers, Xenon and Mirage rear mechs). This is not a company resting on its past glories.

rustychisel

Dorian Gray wrote:

wildmoustache wrote:

no ... one cannot help but be impressed with the engineering innovation over the last couple of years... even cheap plastic composites where appropriate (Xenon levers, Xenon and Mirage rear mechs). This is not a company resting on its past glories.

No, you're right, and you've certainly convinced me that Campagnolo is a force to reckoned with for it's pioneering work in cheap plastic composites. :twisted:

cougie

Dorian - I seem to have clunked all my cranks on the pavement somehow - for me certainly - CF isn't a good choice for cranks.

aracer

Well nobody's forcing you to get them - I'd suggest that if you clunk your cranks on the pavement a top end crank isn't for you, and there is now and will be for the forseeable future plenty of choice in low-mid level alu cranks. Doesn't mean those of us who do look after our top end kit won't benefit.

Nowt wrong with cheap plastic composites for certain applications - just a shame people get all snobby about it, as they're actually a better material for some jobs from a strength/weight perspective than alu. Of course cf is better, but a lot more expensive.

cougie

Sure - I'll just stick to my 'top end' alloy DA cranks then aracer. I'm v happy with them.

Niland

Nice cranks, if it pushes down the price of campy cranks a bit that would be even nicer!

and eh Pliptrot? What the heck are you on about?

maddog 2

surely all carbon cranks have alu inserts to some degree....?

for the pedal threads, the c/ring bolts and to bond to the main axle.

being picky about the Shimano cranks being "carbon-wrap" seems a tad harsh. Feel free to correct me.... 8)

kmahony

They're nicer to look at than the previous DA, 105, R700 chainsets, but I think the new Ultegra SL has the best look (from Shimano)

wastelander

Hmmmmm....to my eye it's just plain wrong. If you want it to look pretty get the Italian stuff, but if you want it to work (and work well!) get Shimano. Is this a nod to the marketing men in the company perhaps? Be it yay or nay, I'll be keeping my FCR600 crankset firmly in place...until they do a compact version, perhaps!

HungryCol

I'm a Shim head but to me it looks like carbon for the sake of carbon. It weight really an issue with the UCI restrictions anyway?
--

drenkrom

Seeing as it is the primary recipient of the Watts coming out of my legs, the crankarm is the component on my bike that gets the "screw the weight" treatment. You can niggle on about saving 20 grams all you want, but it's worth nothing if it starts flexing when you sprint, which is what I've experienced with all carbon crankarms I've jammed power into, Campag included. If I was sponsored, I'd ride them, but til then there are some things good old metal does better than super-fly carbon.

Dorian Gray

Carbon fibre has the potential to be significantly stiffer than aluminium. As always, the key is in the design. If stiffness were automatically proportional to weight then any old Joe in his garage could come up with a great crankset. The truth is, some designs are better than others.

Here's a PDF file from FSA about their K-Force Light crankset, which has a hollow carbon fibre design. It contains the following relevant graphic:



The numbers come from a test by independent German laboratory EFBe, though I couldn't find them on EFBe's website. From these stiffness-to-weight ratios and the published weights of the cranksets, we can work backwards to find the relative stiffness of the cranksets, from stiffest to most flexible:

Campagnolo Record (carbon) - 692 grams - stiffness value 1.000
SRAM Force (carbon) - 791 grams - stiffness value 0.965
FSA K-Force Light (carbon) - 633 grams - stiffness value 0.955
Shimano Dura-Ace (alloy) - 740 grams - stiffness value 0.838
Stronglight Compact Pulsion (carbon) - 600 grams - stiffness value 0.776

Published weights may vary slightly from actual weights as tested by EFBe, but they'll certainly be close enough to make the above comparison valid.

So what do we see? The stiffest crankset, Campy Record, is made of carbon. The crankset with the best stiffness-to-weight ratio, the FSA K-Force Light, is made of carbon. The crankset with the lightest weight, the Stronglight Compact Pulsion, is also made of carbon. The only aluminium alloy crankset, Shimano Dura-Ace, is among the heaviest and also among the most flexible. (Looking at these numbers, SRAM may have over-engineered their Force crankset to eliminate the risk of getting an early reputation for broken cranks.)

Now, if Shimano's claims of 10% greater stiffness (over current Dura-Ace) and weight of 709 grams for the new half-carbon crankset are accurate, the stiffness-to-weight chart would look like this:

FSA K-Force Light (carbon) - 633 grams - stiffness-to-weight ratio 0.188
Campagnolo Record (carbon) - 692 grams - stiffness-to-weight ratio 0.180
Stronglight Compact Pulsion (carbon) - 600 grams - stiffness-to-weight ratio 0.161
Shimano Dura-Ace (carbon) - 709 grams - stiffness-to-weight ratio 0.161 (equal to Stronglight)
SRAM Force (carbon) - 791 grams - stiffness-to-weight ratio 0.152
Shimano Dura-Ace (alloy) - 740 grams - stiffness-to-weight ratio 0.141

And the absolute stiffness chart would look like this:

Campagnolo Record (carbon) - 692 grams - stiffness value 1.000
SRAM Force (carbon) - 791 grams - stiffness value 0.965
FSA K-Force Light (carbon) - 633 grams - stiffness value 0.955
Shimano Dura-Ace (carbon) - 709 grams - stiffness value 0.922
Shimano Dura-Ace (alloy) - 740 grams - stiffness value 0.838
Stronglight Compact Pulsion (carbon) - 600 grams - stiffness value 0.776

I'd like to know the orientation of the test load applied by the EFBe lab before making a certain conclusion, but it looks like carbon is the way to go for both stiffness and low weight. Placebo effect of metal equating with stiffness notwithstanding.