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Engineer tears apart Cervelo quality control esp. BB shell tolerances (video)

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bludger:
https://www.youtube.com/watch?v=GWDztuezn0g

I hadn't heard of this guy before but apparently he's an airbus engineer who is also big into bikes, and sells his proprietary handmade aftermarket PF BBs. One thing is for sure he really doesn't like:

Cannondale

Zipp

And now Cervelo

It's a long video (49 mins) but really eye opening for me. I have always been wary of PF BBs, but I didn't know how blatant poor quality seems to be in the 'premium' bike frame market.  :o

DuncanM:
Hambini is astonishingly rude about a lot of stuff. Not just frames, but wheels, aero processes, aero testing in windtunnels and in general. It's strange, because he claims to be an empiricist, but puts theory above data (ie how much faster people go for similar watts) when criticising wind tunnel time.

I've not come across a video of his where he does like a piece of bike equipment.

Brucey:
it is a source of considerable irritation to competent  professionals in any field when products are sold to consumers as 'the best', (usually on a tidal wave of hype, half-truths and outright bullshit, much of which is lapped up by an incompetent and unquestioning cycling media, with strong 'windsock' tendencies) when any proper  scrutiny of these 'facts' shows that the claims are wildly overstated (may only apply under certain -highly unlikely- circumstances) or are downright wrong.

I'm not claiming that I have myself reviewed his every utterance or indeed that I am competent so to do. But in areas where those things do apply I have largely agreed with what he has said, (which is a very rare thing).  In addition I read something I didn't agree with on his website and sent him an e-mail; probably it was just a typo or an oversight of some kind but I got back a polite and well-considered response.

I think the world of cycling is all the better for having folk who (for the most part) don't have a  substantial vested interest in such products yet have the interest and technical competence to  review the claims made by manufacturers. 

I recently met an engineer who used to work for Cervelo. They do some clever stuff, no mistake about it, (and he wasn't about to air dirty laundry either  by any means) but they do a lot of things in exactly the same way as other cycle manufacturers do it too, and this often is not without compromise.

One of the greatest fallacies in cycling is that cartridge bearings are 'always better'.  They can be excellent, but in bicycles they are usually nothing of the kind; the usual outcome is that a bearing (of unsuitable, unknown or uncontrolled tolerance and specification) is boshed into a housing (similar) by someone who neither knows nor cares about such things. That it works at all for more than five minutes is a ruddy miracle; that it is usually very far from perfect is almost guaranteed.

It is worth noting that both Campag and Shimano have stuck with cup and cone bearings for their top-of-the-line hubs; this is for the very good reason that they can always be adjusted (by a competent mechanic) to single digit (in microns) clearances/low preloads, which would be very difficult to consistently achieve using cartridge bearings.  Of the current range of bottom bracket 'standards' it is very much a question of 'choose your poison'; none of them are perfect or are ever likely to be.

cheers

toontra:

--- Quote from: DuncanM on 15 October, 2019, 12:52:04 pm ---Hambini is astonishingly rude about a lot of stuff. Not just frames, but wheels, aero processes, aero testing in windtunnels and in general. It's strange, because he claims to be an empiricist, but puts theory above data (ie how much faster people go for similar watts) when criticising wind tunnel time.

I've not come across a video of his where he does like a piece of bike equipment.

--- End quote ---

He also seems to go for named individuals in companies, almost to the extent of stalking.  I'm surprised he hasn't faced legal action.  And his use of profanity, whilst mildly amusing in a puerile sort of way, stands at odds with his purportedly empirical analysis - almost as if it were an add-on to get clicks (heavens forbid  ;D).

bludger:
I don't see how swearing contradicts expertise. I've met people who swear like mad in my career who were excellent at their jobs. People spend thousands of pounds in bikes and bike stuff. I know some students who work day in day out either studying or money working who use their cash to buy cervelo and zipp products after months of saving, I'd be pretty annoyed if I was wise to their antics too.

I don't think he even swears that much anyway. Perhaps that's my rough construction ways showing.


--- Quote ---I've not come across a video of his where he does like a piece of bike equipment.
--- End quote ---
He seems to rate Look and Time pretty highly. In a recent vid he's fettling a 2003 Look frame into a racing bike which he reckons will be just as quick as a modern whizz bang.

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