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  #1  
Old 03-16-2018, 04:40 PM
eddief eddief is online now
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Rivendell geomtries

I should know this by now but I don't. I get why GP prefers longer chainstays but why does he "lean toward" slacker than most seat tube and head tube angles?

Just the facts please rather than ragging on GP.
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Old 03-16-2018, 04:43 PM
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charliedid charliedid is offline
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Comfort and stability.
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Old 03-16-2018, 05:15 PM
Frankwurst Frankwurst is offline
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Comfort and stability.
And there you have it.
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Old 03-16-2018, 05:24 PM
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Pegoready Pegoready is offline
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Slack STA means less weight on the hands, plus it's better for saddles like Brooks which feature short and rearward biased rails and warrant slack STA's.

Slack HTA's are just a result of the above. The slacker the STA, the shorter the front-center for a given top tube length. The shorter the front-center, the more toe overlap. One can compensate for the slack STA with a slack HTA and more fork rake.
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Old 03-16-2018, 05:52 PM
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josephr josephr is offline
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Quote:
Originally Posted by Pegoready View Post
Slack STA means less weight on the hands, plus it's better for saddles like Brooks which feature short and rearward biased rails and warrant slack STA's.

Slack HTA's are just a result of the above. The slacker the STA, the shorter the front-center for a given top tube length. The shorter the front-center, the more toe overlap. One can compensate for the slack STA with a slack HTA and more fork rake.
J.R. "Bob" Dobbs approves of this lesson in slack!
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  #6  
Old 03-16-2018, 06:19 PM
merckx merckx is offline
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Rivendell geo is squarely in my wheelhouse. Years ago I began hammering my saddle rearward on a Colnago with my palm to get my ass where it belonged. I even ground off the front of the seatpost cradle to eek-out an additional few millimeters. Merckx Century geometry, and then Dario delivered me to the end of my competitive career with adequate setback. Rivendells are cool. Just don't Fasterbackwards them.

PS: I currently own an Atlantis, and it is sublime.
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  #7  
Old 03-16-2018, 06:29 PM
moobikes moobikes is offline
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Rivendell also likes to put their customers in a more upright position with swept back handlebars - better done with slack seat angles.
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  #8  
Old 03-16-2018, 06:33 PM
merckx merckx is offline
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Originally Posted by moobikes View Post
Rivendell also likes to put their customers in a more upright position with swept back handlebars - better done with slack seat angles.
I don't disagree with this, but they can also be built Fasterforward.
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Old 03-16-2018, 07:59 PM
Ken Robb Ken Robb is offline
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I had an Allrounder (like an Atlantis) that I rode with Nitto Noodles in a Technomic DeLuxe stem and then with Moustache Bars in a Dirt Drop stem. It was good either way but advancing years and arthritis made me happier with the latter set-up.

I'm still hoping (pretending?) that I can fiddle bars/stems to get as comfy on my Strada Bianca and my Rambouillet. The latter will probably be the better candidate for an old guy set-up.
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  #10  
Old 03-17-2018, 11:21 AM
belopsky belopsky is offline
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I itch towards "Fasterforward" but I don't race and typically just lone-wolf it and compete against myself, so I always go back to slacker geometries. My Gunnar Crosshairs went from a 11speed Shimano 105 to a Shimergo 10 shifting 8 to an 8 speed all friction. Might need to get the bars a bit higher
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Old 03-17-2018, 02:27 PM
cachagua cachagua is offline
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Quote:
Went from a 11speed Shimano 105 to a Shimergo 10 shifting 8 to an 8 speed all friction. Might need to get the bars a bit higher...
That's the spirit! I've been collecting parts to set my Atlantis up 8-speed.

As far as its geometry -- I've built a stand that allows me to make fairly precise measurements of stack & reach, seat setback, seat-to-bar drop etc., and part of what I hope this will show me is what effect wheelbase and front center/chainstay variations have on the way the bike feels, when I'm sitting in exactly the same place relative to the pedals and bars. The Atlantis will be pretty much the outlier, compared with all the road bikes and the all-road bikes, so the effects (whatever they turn out to be) should be exaggerated and easy to perceive... should be an interesting process.
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  #12  
Old 03-17-2018, 02:36 PM
MikeD MikeD is offline
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I think slacker seat tube angles go better with Brooks saddles.


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