Pinarello Dogma K8-S

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wheelsONfire
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Joined: Mon Jul 07, 2014 8:15 am
Location: NorthEU

by wheelsONfire

Only thing i have been told with dampers, you need to spin more smooth or you'll have a pogo effect.
If i would have an option, either for K8-S or the forthcoming model with no suspension, i would take the K8 none S version.
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.

by Weenie


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XCProMD
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Location: Cantabria

by XCProMD

One problem with these designs in road applications is antisquat. The relative position between rear axle and bottom bracket, plus chainring-cog sizes and added to the fact that a road bike is suppose to have short chainstays, make for a very difficult placement of the flexing part of the rear triangle.

With composites it is easier to add some damping into the frame, but still damping in the shock is needed. Then is all a matter of shimming according to the frequencies to be absorbed and those that not.

TheKaiser
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Joined: Thu Sep 05, 2013 3:29 pm

by TheKaiser

XCProMD wrote:One problem with these designs in road applications is antisquat. The relative position between rear axle and bottom bracket, plus chainring-cog sizes and added to the fact that a road bike is suppose to have short chainstays, make for a very difficult placement of the flexing part of the rear triangle.


In my experience with soft tail mountain bikes (Moots YBB, etc...) you have just described the exact problem. There seems to be some belief amongst the designers that the short travel of these types of designs exempts them from the need for proper suspension kinematics. As a result, these types of designs have very poor anti-squat figures, as increasing the anti squat would necessitate a more radical frame design, and so why would the designer bother if it doesn't matter in this application?

The problem is that it does matter, even with the short travel. I recall seeing many soft tail MTBs bouncing up the smooth climbs with each standing pedal stroke just as much as a long travel bike with proper kinematics and a plaftorm valved shock. The only difference is that the short travel bike is cycling through 50% of its travel whereas the long travel bike is cycling 10%, but they both still bob 12mm!

Moots even came up with a "Lockout" For their YBB, which was a QR lever on the rear shock collar, and when you would flip it it would clamp down on the shock shaft, binding the thing up.

Having said all of that, I think it would be possible to do this right, with either slightly elevated chainstays, or if you curved the chainstays upward and then back down, so that the flex pivot was at the top of the curve. That could let one tune the rear axle arc to provide some anti squat.

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53x12
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by 53x12

Be curious to see how this K8-S does sales wise for Pinarello. I doubt the target audience watches Flanders or Paris-Roubaix. But I wouldn't call their launch of it (in terms of races) a great success.
"Marginal gains are the only gains when all that's left to gain is in the margins."

LionelB
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Location: Aix en Provence

by LionelB

It will for sure be a low volume frameh

lbs0927
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by lbs0927

Pinarello Dogma is very wxpensive!!

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wheelsONfire
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Joined: Mon Jul 07, 2014 8:15 am
Location: NorthEU

by wheelsONfire

53x12 wrote:Be curious to see how this K8-S does sales wise for Pinarello. I doubt the target audience watches Flanders or Paris-Roubaix. But I wouldn't call their launch of it (in terms of races) a great success.


No, but it seems a K8 without suspension will appear. That could probably be a wiser choice. Personally i think i would stick to standard F8.
I guess most would!
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.

HanSolPark
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Joined: Wed May 06, 2015 7:38 am

by HanSolPark

that looks great. Im curious that will be effective in gravel.

jefftillack
Posts: 28
Joined: Mon Sep 22, 2014 6:09 am

by jefftillack

Nice machines, however too expensive for me! I recently bought a new Lapierre Pulsium 500 and for the cost (43500 Aussie), it's a superb bike. I wouldn't say it's a fast bike, in comparison to my TCR anyway, but its level of comfort is outstanding. I live in an area with bitumen roads that are rougher than most dirt ones, so the comfort has been really noticeable. The elastomer in the Pulsium top tube only runs to 3.5mm, so it's not in the league of the Pinarello (10mm), but it takes off just enough vibration and road chatter to make it a comfortable, all day machine. There's no noticeable bobbing either with that small amount of travel. A big plus for me was the racier geometry over the stock Domane's etc - it still looks like a race bike and not a "comfort" bike ( IMHO only). Fitted it out with some (changed the hub) Campy Shamal's and the weight has certainly dropped off. Came with heavy training wheels which were boat anchors.

Something different from what everyone is riding anyway. The look does grow on you. Wasn't sure about it at first, but love it now (in FDJ colours) after 3 months of smashing it over the worst roads around.

cany
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Joined: Wed Jul 29, 2015 7:55 am

by cany

Endurance best frame was born

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