Low weight cranksets benefit?

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Marin
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by Marin

I can report back if the Red crank is better at absorbing road buzz (that's the technical term, right?) than the Force 22 one. I'll do the swap this weekend :)

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wheelsONfire
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by wheelsONfire

I would be less than happy if i bought an expensive light weight crankset and it proves shifting is less precise than Shimano DA.
I have no experience in the lighter aluminium cranks and chainrings (or carbon for that matter). Rotor worked better than expected. Actually it shifted precise and fast.
I figured i would try something else now. Perhaps this comes down to personal preference (what really is adequate shifting quality)?
What one like, the other one might not be satisfied with?
I was Told THM cranks is always the safest bet when it comes to light weight cranks. THM firmly recommends Praxis chainrings when i asked them.
This due to superior shifting compared to some other, esoteric brands.
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

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dadoflam08
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by dadoflam08

IMO the benefit of a light crank is in reducing overall bike weight rather than performing better than a heavy one.

I have owned several cranks - Ultegra 6800, DA 10spd, SR 11spd, Athena 11 spd, Zipp Vumaquad and Ax Lightness Morpheus. I was neither able to detect that a lighter crank performed better due to lower weight or that it performed worse due to potential flexing. On test results I believe the Ultegra 6800 is the stiffest I have ridden - it even tested stiffer than the DA 7800 crank - but can't say I detected much (any) difference over the Zipp or Ax crank - even though I weight over 90kgs.

I would agree that shifting quality is far more important - I spent many times putting the chain back on the Zipp crank (I should state that it was being used in conjunction with SRAM Red Mk 1) than I have with the DA or SR cranks - principally due to chainring quality.

Unless you are going all out for a sub 5.5kg build I would recommend staying with DA or Campy SR cranks and spend the money saved elsewhere. If you are going all out the new THM Clavicula or Ax Morpheus with Praxis rings will save you a couple of hundred grams - but wont perform any better just because they are lighter.

Changing cranks to dampen road buzz? - get thicker socks
'83 De Rosa+'11 Baum Corretto+'08 BMC Pro Machine >6kg+'86 Pinarello Team +'72 Cinelli SC +'58 Bianchi+'71 Cinelli SC+'78 Masi GC+'83 La Redoute Motobecane+'94 Banesto Pegoretti+'88 Bianchi X4 +'48 Super Elliott+'99 Look Kg281+'18 Pegoretti

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bigfatty
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by bigfatty

I went from 2004 Centaur Crankset with old style bottom bracket to FSA K-Force Light with 386 BB and I have not noticed any difference except I have to be a hell of a lot more careful not to smash the carbon arms against steps or the sidewalk. if anything, I feel, with absolutely no justification, that the 386 BB has made a big difference, even though I can not feel anything.

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wheelsONfire
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by wheelsONfire

I have wondered, the tests seen at various components vs what riders subjective impressions of them are, to me it seems they are not same very often.
The quest for weight savings should never trump the usuable quality. If so, something is seriously off track.

Sure, aluminium surface may not be as prone to be damaged as clear coated carbon. I guess it's same with these fixed spider carbon cranks. It is far too easy to crack bolts holes or ending up with a pile of parts if dropping the bike. Last season i slided in a corner and cracked a few ribs, scraped up a bit. My first concerns were the bike.
Looking at facts of this outcome, i understand that if it had been my light weight carbon ride, it had been damaged seriously. With my Ti ride, hell, nothing.
If i drop a chain scraping a nice carbon crank it's peeling clear cloat, maybe heel rub can cause this to. If so, it is sanding and leaving it for a new clear coat that is the deal.
Take a dive and maybe the thing cracks and an alu version crank, well, i kind of doubt it happens much but a few scratches.
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

kenmical
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Joined: Thu Oct 02, 2014 3:25 am

by kenmical

Crank is the last place I will look to for comfort. It should have a super smooth bearing to reduce rotational force. Then stiff for sprints, out of saddle climbs and durability. There are cases of DA hollow crank broken into two pieces. There is also feedbacks that SRAM Red chain rings flexing under heavy load. Campy Titanium is not as lasting etc. Different peeps have different 'feel' at the end of the day. So most important is stiff and smooth to me.

Marin
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Location: Vienna Austria

by Marin

Switched from Force 22 to Red Exogram, don't feel a difference. The bike is now 6.1 kg though - saved 114g :) The force crank was a bit prettier however.

Regarding scrapes, carbon fares much better than painted or anodized aluminum since it's black all the way through.

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wheelsONfire
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by wheelsONfire

Marin wrote:Switched from Force 22 to Red Exogram, don't feel a difference. The bike is now 6.1 kg though - saved 114g :) The force crank was a bit prettier however.

Regarding scrapes, carbon fares much better than painted or anodized aluminum since it's black all the way through.


Nah, that is not really true about carbon cranks.
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

Marin
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by Marin

It is for mine, got XTR, Rival OCT, Force 22 and Red.

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wheelsONfire
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by wheelsONfire

I ment that carbon cranks that get banged, can crack. The cranks are hollow, so it seems they would be similar to an impacted carbon frame.
Have you banged an aluminium crank? I have, but no carbon. The alu crank did not get damaged very badly, only bruised.
But sure, if you aim at the anodised surface gets bruised, or polished surface gets ugly, you're right!
I may also say, i am not 100% sure, this is merely speculations on carbon cranks(arms) ability to withstand impacts from crashes, dropping bike or similar.

Anyways, i aim to run the FSA K-force light crankset (due to the match of my frame). I may see if i can detect the vibration dampning effect you mention.
Not that i have suffered using alu cranks. I mostly dislike when seat posts seems to transfer vibrations all the way through the saddle.
To me it seems it goes up the spine at times. I don't like that since i have some issues with my back.
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

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wheelsONfire
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by wheelsONfire

Dang, i just got my black FSA K-Force Light, 172.5mm, 52/36 set. It's weight is a mere 560g!
That is light with respects to the sturdy chainrings :-D
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

VTBike
Posts: 383
Joined: Mon May 16, 2011 8:14 pm

by VTBike

I think it's just one key component on your way to an overall light bike. I don't believe a lightweight crankset - just the weight itself - makes any difference, unless your coming off of a super heavy crankset and saving like a pound or something.

Now, if your goal is a reasonably light bike in the 13-15 lb range, a light crank is a must to get there -- and then, when your bike overall is lighter, you'll notice the difference and synergies of all the lightweight components working together.

I've always had Red on my bikes.. but have ridden rival and ultegra at times. Perceptibly, when it comes to the crank, i feel little or no difference. Especially with similar groups like Rival and Red. Again, if your goal is a light bike - you should just go for the lightest you can afford, always.

VTBike
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by VTBike

wheelsONfire wrote:I ment that carbon cranks that get banged, can crack. The cranks are hollow, so it seems they would be similar to an impacted carbon frame.


Understandable why you might think this, but far from the truth. The carbon layup in cranks is much thicker than a frame. The function and placement of a crank is unique, and crank makers are smart enough to design for this. I think it's going to be quite difficult for you to hit any carbon crank hard enough to crack it - especially on a road bike. I also have carbon cranks on my MTB, and have hit them pretty dang hard. They mark up, even chip.. but nothing serious enough to cause serious damage.

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vejnemojnen
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by vejnemojnen

Sorry for this, but did not want to open a new thread for this question of mine. :) Just want to ask for some opinions&thoughts

Came across an advert in a german classified.. 99 euros plus shipping, which is very reasonable&cheap.

some BB30 chainset, cannondale SI, albeit, two-piece, FSA-manufactured, some pics:

Image
Image
Image

anyone thinks it'd be a nice upgrade for swapping my FSA energy chainset? 99 euros is not that much (around 111 USD?) and the chainset is new, according to the seller..

Worth it?

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

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wheelsONfire
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by wheelsONfire

I have no clue. The new FSA K-Force Light uses the lock-ring at none driveside, it's also a hidden chainring bolt at the driveside arm.
I guess this is one question you have to just guess. Either you go for it as the price seems very cheap, or you skip it?
For me it kind of served a purpose, The BB386 EVO is correct BB standard for me, so i need no spacers. I also lowered weight and it seems i will still have good stiff chainrings and shifting.
But it also cost a great deal more than the above set. I weighted my kit. Driveside with 52/36 chainrings (172.5mm arms) is 430g, none driveside is 130g.
So it's 560g which i find pretty light as chainrings are as sturdy as DA 9000 versions.
The crank looks very very nice. I think the looks (black) was better than i expected!
My DA crank was 684grams (52/36 and 172.5mm arms) and Rotor 15-20 grams more than DA but with 175mm arms and Aero Q-rings (52/38).
Shimanos spindle is very thin and also only 24mm. Both FSA and Rotor has a 30mm spindle which seems significantly stiffer.
However, i must compliment Shimanos preload system. It is very easy to load bearings so we get a very good roll.
I have yet to see how FSA is in this aspect.
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

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