EBay CNC Crank

Discuss light weight issues concerning road bikes & parts.
whydobearsxplod
Posts: 159
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by whydobearsxplod

I bought a set of these on a whim under the brand mk3. Confirmed weight is 335g with alloy fixing bolts in 170mm length.

Image

They are actually labeled with brand "ace" and the part number a1611ke03.

I want to test them out (probably on my rollers to start), but I need a square taper JIS bottom bracket first.

Anyone have experience with these cranks? Any idea about spindle length I should get?

My bike has 68mm shell.
Last edited by whydobearsxplod on Wed Sep 27, 2017 9:16 pm, edited 2 times in total.

by Weenie


whydobearsxplod
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by whydobearsxplod

Some detail of the CNC-job on the reverse side of the cranks in case anyone is curious.



ImageImage

shimmeD
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by shimmeD

http://www.wiggle.co.nz/shimano-bb-un55 ... sh-thread/
Yes, see what you mean now when asking what length. Never thought of it before, because I had always bought Campag Chorus (which I see now comes in 102mm). Maybe you just get one that suits what you want in terms of Q factor.
Sorry I'm not of much help. But I also came to comment that those cranks look interesting reminding me of Tune (Bigfoot?) and good weight. Heard that the Tunes were flexy, but what would I know. Certainly interested to see how you find/compare with your existing cranks, for sure.
Less is more.

bm0p700f
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by bm0p700f

what is the link. I fancy getting one as well.

whydobearsxplod
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Location: Santa Barbara

by whydobearsxplod

I am currently using KCNC K-Type (130 BCD).

Here is the link that I bought from. However, I see this being sold by others- even with anodized spiders. For whatever reason, many of the listings include "Brompton" in the title. Search for Brompton crankset and you will find a bunch of listings.

https://www.ebay.com/i/282259311637


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eric01
Posts: 530
Joined: Mon Feb 06, 2006 1:06 am

by eric01

Wow those are pretty cool looking. Reminds me of the Topline cranks from the 90s.

Ha! Just clicked the ebay link and it even says Topline in the listing name
AX Lightness Vial Evo, Carl Strong Titanium

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prendrefeu
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by prendrefeu

Why do I have a feeling these will be noodles?
Exp001 || Other projects in the works.

eric01
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by eric01

I'm sure they will be. The Toplines back in the day weren't exactly known for their stiffness and that was compared against the dura-ace's and record's of the 90's. No way it'll compete with 30mm spindles and super fat crank arms

But they do look super cool. Don't race them but it'd be a nice for a club ride conversation.
AX Lightness Vial Evo, Carl Strong Titanium

whydobearsxplod
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by whydobearsxplod

The closest recent equivalent to these in design is probably the Tune Bigfoot which also used square taper. The "fastfoot" I think is the same design but using the Tune "sixpack" hex taper bottom bracket.

From what I can tell, these are probably 50-60 grams lighter than the Bigfoot of comparable dimensions.

Both cranks are machined from 7075. So, where is the weight coming from?

Here's a photo of the back of the Tunes:

Image

And here are the "Ace" cranks:

Image

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Asteroid
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by Asteroid

Cool lookin' cranks. PM me if you want to try out an old square taper 105-level bb. 68x103.
It came off a DeBernardi track bike. Very slight roughness if memory serves, but clean threads.
I only ask you reimburse me via paypal for the mailing cost.
Probably three or four bucks regular mail. It'd get to you relatively quickly, since I live near Pasadena, CA.
Oldbie

whydobearsxplod
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Location: Santa Barbara

by whydobearsxplod

Thank you Aestroid. :beerchug:

Let me check to see if 103 will be enough in a double chainring setup with these and I might take you up on that offer. Eventually I would like to get something light with a titanium spindle, but I think it is best to try out the spindle length first before I invest in anything.

tmr5555
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by tmr5555

Why are they not available in bigger lengths?

glepore
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by glepore

At some length they probably get very flexy/break prone. My original toplines had pedal holes that were solid in the back, as many of the early ones fractured there. Precludes the use of pedals without flats.

At my weight (58 kg) they were fine. Bigger guys that aren't spinners might beware. Not sure what spindle length will be needed, I think i used 109's with mine that were originally mtb cranks (done that way to get the 110 bcd, q factor be damned).
Cysco Ti custom Campy SR mechanical (6.9);Cannondale SS Evo Di2 7970 (5.79); Willier Cento Uno Air Di2 9070 (7.0); C40 Mk2 DA 7800 ; Anvil Custom steel Etap;1996 Colnago Technos Record

whydobearsxplod
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by whydobearsxplod

In comparing the ebay cranks to the Tune cranks, it is clear that the milling is quite a bit more generous on the ace cranks. Somehow, it doesn't look like 50 grams more to me.

The milling pattern looks very intentional and "engineered" on the bigfoot. Since it is Tune, I am sure they chose the material distribution very carefully for stiffness and strength. The ace cranks look like someone took a melon baller to the back of them.

Another modern crank for comparison is the Extralite QRC 2 designed using FEA. The previous model (ebones QRC) is shown below. Extralite mills a kind of spine down the middle of the back of the arm. I think this is what they call the "stress split design". The spider design is very similar in the Ace, except extralite builds one of the chainring bolt holes into the crank arm!

Image

whydobearsxplod
Posts: 159
Joined: Tue May 08, 2012 3:10 am
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by whydobearsxplod

tmr5555 wrote:Why are they not available in bigger lengths?


170 is the longest I can find. My current cranks are 172.5. Let's see how sensitive my legs are to the 2.5mm...

by Weenie


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