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  #511  
Old 09-10-2024, 11:39 PM
chismog chismog is offline
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Quote:
Originally Posted by slowpoke View Post
Can someone check my math here?

According to Geometry Geeks, the Look 585 in a medium supposedly has a reach of 386mm: https://geometrygeeks.bike/bike/look-585-2008/

Checking the geo chart, and calculating it, I get a different reach.

585 geocharts:
https://ep1.pinkbike.org/p4pb14497764/p4pb14497764.jpg

This should just be virtual top-tube - setback from BB (B - E), right?

Calculating my own E here:
Code:
sin (90º*- STA) * A1 - we want A1 because it meets with B in the diagram
= sin (90º - 73.73º) * 530
= 0.27982901 * 530
= 148.3mm - this matches up with the E in the chart
The virtual top-tube B is 545mm.

545 - 148.3 = 396mm for reach.

This seem right? Thanks!
I didn't check your math, but I did check your variables. In the chart, there are three lengths shown for seat tube. There's a mistake in the chart!

A1 cannot be longer than A as shown in the drawing. But it is in the chart. Comparing this against my own 585, I see that in reality:

A1= Actual, center to top
A2= Actual, center to center
A= Virtual (traditional size), center to center.

So my my large is 53.5 to top, and it fits about like a 55-56.

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  #512  
Old 09-11-2024, 12:35 AM
slowpoke slowpoke is offline
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Quote:
Originally Posted by chismog View Post
I didn't check your math, but I did check your variables. In the chart, there are three lengths shown for seat tube. There's a mistake in the chart!

A1 cannot be longer than A as shown in the drawing. But it is in the chart. Comparing this against my own 585, I see that in reality:

A1= Actual, center to top
A2= Actual, center to center
A= Virtual (traditional size), center to center.

So my my large is 53.5 to top, and it fits about like a 55-56.

Thanks Chris! Oh gosh, why didn't I even think of that! Blindly looking at the numbers without seeing if they even make sense....

Also, I realized that stack and reach are calculated at the top of the headtube, but B is based on the top tube/headtube junction. so we need to factor in K + K0 to get that.

The stack in my diagram is wrong because I'm relying on the incorrect seattube, but the reach should be.

I'll update things again in the morning with your new findings. Thanks!
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  #513  
Old 09-11-2024, 09:55 AM
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thwart thwart is offline
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Quote:
Originally Posted by chismog View Post
So my my large is 53.5 to top, and it fits about like a 55-56.

I’d agree. My large fits like a 56.

With a 20 mm setback post, the saddle in a slightly back position on the post and a 100 mm stem, my saddle tip to bar measurement is approximately 54 cm, FWIW.

Here’s a pic shortly after I built it up and before final bar tape application. Saddle height is 75.5 cm.

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Last edited by thwart; 09-11-2024 at 09:57 AM.
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  #514  
Old 11-12-2024, 02:01 AM
bthomas515 bthomas515 is online now
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This thread inspired me to pick up a 585 origin - I’ll post a pic and some impressions when I get it out later this week
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  #515  
Old 11-12-2024, 08:59 AM
jamesdak jamesdak is offline
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Originally Posted by bthomas515 View Post
This thread inspired me to pick up a 585 origin - I’ll post a pic and some impressions when I get it out later this week
Looking forward to your impressions. I keep missing out on the local ones. I did land a 2006 555 that I just upgraded the parts to DA on. But I've only got one ride on it so far. The seatpost clamp bolt is stripped and I haven't been able to get it off yet.

If being honest though, the one ride did not blow me away like the first ride on my Colnago C40 did.
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  #516  
Old 11-12-2024, 10:40 AM
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thwart thwart is offline
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Originally Posted by jamesdak View Post
If being honest though, the one ride did not blow me away like the first ride on my Colnago C40 did.
But of course, 555 ≠ 585.

I’m certainly not someone who has a lot of experience with carbon frames, but having owned a B-stay Colnago C40, a Look 361, a Look 481SL and a Parlee Z4 in the past… the 585 is significantly better in terms of ride feel not being sacrificed for rigidity.
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  #517  
Old 11-12-2024, 11:28 AM
jamesdak jamesdak is offline
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Originally Posted by thwart View Post
But of course, 555 ≠ 585.
That's obvious.

Price was too good to pass up and I'm curious to see how it compares to the other C.F. bikes I have. It is the newest.

Still hoping to land an economical 585 one day.
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  #518  
Old 11-12-2024, 11:59 AM
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thwart thwart is offline
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Originally Posted by jamesdak View Post
That's obvious.

Price was too good to pass up and I'm curious to see how it compares to the other C.F. bikes I have. It is the newest.

Still hoping to land an economical 585 one day.
It's worth the search.

What's surprising given when it was designed is it will fit (although barely) generous 28 mm tires like these Schwalbe Ones. Those 27 mm Vittoria Paves shown above on the shake down ride fit easily. I assume being used at Paris-Roubaix was foreseen.

I've owned mine now for a couple of years. Lived up to my high expectations... definitely a keeper.

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  #519  
Old Yesterday, 08:13 AM
bthomas515 bthomas515 is online now
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Went on a quick 10 mile sprint before dark. Can’t make very definitive claims, but can say that it is noticeable how comfortable it is. A few miles were on a bike path and you just did not feel the bumps or breaks in pavement.

Also, older handlebar shapes suck.
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