The all new Pinarello Dogma F8...

Discuss light weight issues concerning road bikes & parts.
TimW
Posts: 473
Joined: Sat May 09, 2009 1:52 pm
Location: England, UK

by TimW

Good to see it's got an almost normal bottom bracket instead of one of the new 'standards' . Just why an Italian thread..(is it to make the eastern made bike look more Italian? :lol: ).

by Weenie


maxxevv
Posts: 1949
Joined: Wed Feb 09, 2005 4:51 am

by maxxevv

Italian threads have a wider diameter compared to English thread. Hence, in theory, its a stiffer interface.

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Calnago
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Joined: Sun Nov 07, 2010 9:14 pm

by Calnago

The main reason Italian threads are functionally obsolete is due to the thread direction. English threaded BB's have a left hand thread on the drive side. Italian threads have a right hand thread, meaning "righty tighty, lefty loosey". The problem with this stems from the way the bearings roll against the surfaces. When you pedal, clockwise, the bearings roll counterclockwise against the spindle. Transfer this to the inner races of the bearing and the counterclockwise force tends to want to turn the bearing counterclockwise (left). With an Italian threaded bb, this means the force is trying to lossen the bearing. This is why you'd often see Itlaian threaded BBs spin loose and unthread themselves from the BB. This can't happen with a left hand thread because the forces will tend to tighten rather than loosen the assembly. Of course, it the Italian BB is properly tight in the first place you shouldn't experience this, but if it is at all loose to begin with (meaning less than really tight), there will be a natural tendency to spin out.
Why Pinarello continues to use this is beyond me. Otherwise, it's a very nice bike. But the marketing spin is quite laughable, but that's pretty much par for the course these days no matter which manufacturer you're talking about.


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Last edited by Calnago on Fri May 30, 2014 8:58 pm, edited 1 time in total.

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Mockenrue
Posts: 377
Joined: Mon Aug 20, 2012 10:32 am
Location: UK

by Mockenrue

Slightly off-topic, but have Sky switched from Veloflex to Vittoria tyres? Looks like Open Corsa CXs on that bike.

Philbar72
Posts: 137
Joined: Tue Sep 17, 2013 9:47 am

by Philbar72

Sky don't have a tyre contract, free to use whatever they wish....

bombertodd
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by bombertodd

Calnago wrote:The main reason Italian threads are functionally obsolete is due to the thread direction.



I love threaded bottom brackets and prefer them on my bikes. I've never had any issues with them. I don't see a real world issue with Italian bottom brackets. 65 Nm of torque is a lot. In practice there should be no possible way a decent working bearing could loosen a bottom bracket torqued to 50+ Nm.

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Calnago
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Joined: Sun Nov 07, 2010 9:14 pm

by Calnago

@Bombertodd: You are correct... if the threaded Italian BB is properly torqued, it should be just fine. But in practice, some don't get properly torqued and these are the ones that loosen up. With a BSA threaded BB, even if it is not quite tight enough, it would not spin out because of it. I'm all for threaded, but get rid of Italian threads. No good reason to be using them.

I am a big advocate of BSA threaded BB's... Hate Hate Hate pressfit BB's. They are a product of the molded carbon frames and it's just too difficult to get them seated in there properly. Boo hoo.... so now we're stuck with all this pressfit crap and the BB manufacturers scrambling trying to come up with decent solutions.
Last edited by Calnago on Sat May 31, 2014 2:05 am, edited 1 time in total.

wkwt
Posts: 122
Joined: Fri Nov 05, 2010 2:16 am

by wkwt

Any link to a ride review? Other than Bicycling...

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russianbear
Posts: 757
Joined: Wed Apr 11, 2012 3:40 am

by russianbear

I like it. More subdued, but still some infuriating (to some) Italian flare. For some reason the fork reminds me of a thm scapula.

Berzin
Posts: 1
Joined: Sat May 31, 2014 5:32 am

by Berzin

It's a sleek looking machine, very elegant.

As for all the hype, we've all been around long enough to know that Pinarello hasn't cornered the market on hyperbole.

ichobi
Posts: 616
Joined: Thu Jan 19, 2012 11:30 pm

by ichobi

A very good bike by all account. Let's wait for the Tour mag test. Oh wait..I thought Pinarello never let them borrow the bike for test.

airwise
Posts: 1049
Joined: Tue Jul 27, 2010 8:31 pm

by airwise

That's probably because Pinarello don't design bikes with the sole intention of passing the Tour deflection tests.

IIRC, The last Dogma had the stiffest BB area of the bikes tested in Le Cycle last year. Didn't win their bike of the year though.

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kgt
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Location: Athens, Greece

by kgt

Le Cycle tests are somewhat subjective but much more sincere ΙΜΟ.

excremanwu
Posts: 100
Joined: Mon Feb 16, 2009 8:29 am

by excremanwu

uncommon to see threaded BB in new top model

Permon
Posts: 640
Joined: Mon Jun 23, 2008 8:52 am

by Permon

Thanx God there is still one producer like that! :thumbup: :beerchug:
It is the only problem free solution. I love it!

I had few problems with press fit systems.....from the moment I have Dogma, I ride bike instead of solving problems with BB and I am happy 8)

Kuddos to PINA! :up:

by Weenie


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