Help with Cervelo sizing
#26
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Well, I think the plan is the same. Get post cut with some room for play (going tomorrow AM). Redo the video fit for knee angle. Then check BB-saddle setback, lower stem/bars and recheck video fit. And refinement from there.
This all really started due to lower back pain (likely from rocking so much in the saddle) and neuropathy in the hands (mainly ulnar > median). So I'm hoping if I can take care of at least one of those issues, I can make it 1-2 months prior to a proper fitting session.
This all really started due to lower back pain (likely from rocking so much in the saddle) and neuropathy in the hands (mainly ulnar > median). So I'm hoping if I can take care of at least one of those issues, I can make it 1-2 months prior to a proper fitting session.
#27
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From: In the foothills of Los Angeles County
I'm sorry, but you are wrong. A given saddle height can be correlated to a specific saddle to bar drop. There's so much information missing here that all others can do is post some information, so the OP can determine what frame size he really has and what the stack and reach might really be. One rider might think that a 4cm saddle to bar drop is plenty, but even as a small rider, I use 10cm. Large riders might use 15cm or more. Large riders may also use extremely long stem and a lot of handlebar reach. I've read of one extremely tall pro rider using at least a 170mm custom made stem. I'm assuming that a person buying an S5 doesn't want to make an endurance bike out of it, but who knows.
#28
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It is for someone that is 1.95m tall.
Mine is only 1/2" less but I am 1.8m.
As I said previously the numbers from your fit calculators were very similar to mine and I just can't see how someone 6" taller would ride the same fit as me.
Something is off and the best way to solve it would be to sort it out in person with someone that is suitably experienced.
Mine is only 1/2" less but I am 1.8m.
As I said previously the numbers from your fit calculators were very similar to mine and I just can't see how someone 6" taller would ride the same fit as me.
Something is off and the best way to solve it would be to sort it out in person with someone that is suitably experienced.
#32
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From: Loveland, CO
Bikes: Cervelo Rouvida x 2
Back to the facts, saddle height and stack predict the saddle to bar drop. With a 73cm saddle height and 530 stack, I'd get a saddle to bar drop of no more than 10cm, with the standard 15mm headset top, no spacers and a -17 stem. A person with a 79cm saddle height would need a stack of 590 to get about the same saddle to bar drop. Your bike has a 630 stack with a lot of spacer and a high rise stem, so there is very little saddle to bar drop. All those spacers and the stem rise all reduce the reach, too. Try removing all spacers and flipping the stem down to create more saddle to bar drop. You'll increase both reach and drop. With a stack that limits the drop to around 6cm with no spacers and a -17 stem angle, there's no way you'll ever have too much drop.
The foot angle of 25 degrees is too much. The saddle should be low enough to allow your heel to drop 2-3cm below horizontal, with the leg fully extended at the bottom of the stroke.
The foot angle of 25 degrees is too much. The saddle should be low enough to allow your heel to drop 2-3cm below horizontal, with the leg fully extended at the bottom of the stroke.
#33
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Right. Which is why I believe the first step is to trim the post to allow 770-790 mm of height, readjust the saddle setback and then work on the cockpit (of course the stem will come down proportionally with the saddle). Going to the LBS this morning and hopefully with have back same-day to readjust everything and redo the video fit.
#34
Facts just confuse people




Joined: Jul 2017
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From: Mississippi
Bikes: Tarmac Disc Comp Di2 - 2020
If you hadn't ignored my advice in post #14 you could have been showing us this stuff much sooner. <grin>
Spam police aren't going to come after you if you aren't a spammer.
Spam police aren't going to come after you if you aren't a spammer.
#35
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Bikes: Colnago, Van Dessel, Factor, Cervelo, Ritchey
Right. Which is why I believe the first step is to trim the post to allow 770-790 mm of height, readjust the saddle setback and then work on the cockpit (of course the stem will come down proportionally with the saddle). Going to the LBS this morning and hopefully with have back same-day to readjust everything and redo the video fit.
#36
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So...
I confirmed new forum users can’t post images or in-line links (like you suggested) until 10 posts. Sorry. Forum rules, not mine.
As far as being a toe down rider, I probably am to a slight degree. But after some experimentation and being very cognizant of my pedal stroke, it is certainly exaggerated by my efforts to reach the 180 degree crank position due to saddle being too high. The video of the aft position makes that clear. We will see when I get the saddle back later today.
I confirmed new forum users can’t post images or in-line links (like you suggested) until 10 posts. Sorry. Forum rules, not mine.
As far as being a toe down rider, I probably am to a slight degree. But after some experimentation and being very cognizant of my pedal stroke, it is certainly exaggerated by my efforts to reach the 180 degree crank position due to saddle being too high. The video of the aft position makes that clear. We will see when I get the saddle back later today.
#37
Facts just confuse people




Joined: Jul 2017
Posts: 19,341
Likes: 7,062
From: Mississippi
Bikes: Tarmac Disc Comp Di2 - 2020
So...
I confirmed new forum users can’t post images or in-line links (like you suggested) until 10 posts. Sorry. Forum rules, not mine.
As far as being a toe down rider, I probably am to a slight degree. But after some experimentation and being very cognizant of my pedal stroke, it is certainly exaggerated by my efforts to reach the 180 degree crank position due to saddle being too high. The video of the aft position makes that clear. We will see when I get the saddle back later today.
I confirmed new forum users can’t post images or in-line links (like you suggested) until 10 posts. Sorry. Forum rules, not mine.
As far as being a toe down rider, I probably am to a slight degree. But after some experimentation and being very cognizant of my pedal stroke, it is certainly exaggerated by my efforts to reach the 180 degree crank position due to saddle being too high. The video of the aft position makes that clear. We will see when I get the saddle back later today.
But come to think of it... they haven't posted much lately. Maybe they did get sent to the spammer prison! <grin>
#38
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Okay! The post was cut 55 mm. The bike went back onto the trainer. Apart from hiccups with the damned stickers falling off my hip, here are the results... Drum roll please...
Saddle set at 800 mm from 825 mm. Saddle setback moved to 98 mm from 90 mm. Cockpit lowered to 100 cm from 103.5 cm resulting in a drop of 6.5 cm (saddle-ground 106.5, bar-ground 100.0). Not certain my core can take much more than that right now. ;-)
I instantly felt the difference. Don't feel I'm rocking like the open seas. My foot is not straining on the down stroke (far more flat pedal stroke). My hands don't hurt as much (less forward weight). I know it isn't perfect but it's a lot better until the formal bike fit in 1-2 months.

Initially, installed the saddle @ 770 mm without changing the saddle setback

Plan: Raise saddle to 800 mm and saddle setback to ~ 98 mm. Checked knee-shaft with plumb bob and dead-center over crank @ 98 mm. Not sure about the extra 12 mm. I know taller riders sometimes have a little crank setback ~ 10 mm - something to ask the bike fitter about

Plan: Lower cockpit by 35 mm. Leave length as-is

The re-check (some of the dots kept falling off so I think there's some error here and made no additional changes)

Velo au natural
Saddle set at 800 mm from 825 mm. Saddle setback moved to 98 mm from 90 mm. Cockpit lowered to 100 cm from 103.5 cm resulting in a drop of 6.5 cm (saddle-ground 106.5, bar-ground 100.0). Not certain my core can take much more than that right now. ;-)
I instantly felt the difference. Don't feel I'm rocking like the open seas. My foot is not straining on the down stroke (far more flat pedal stroke). My hands don't hurt as much (less forward weight). I know it isn't perfect but it's a lot better until the formal bike fit in 1-2 months.

Initially, installed the saddle @ 770 mm without changing the saddle setback

Plan: Raise saddle to 800 mm and saddle setback to ~ 98 mm. Checked knee-shaft with plumb bob and dead-center over crank @ 98 mm. Not sure about the extra 12 mm. I know taller riders sometimes have a little crank setback ~ 10 mm - something to ask the bike fitter about

Plan: Lower cockpit by 35 mm. Leave length as-is

The re-check (some of the dots kept falling off so I think there's some error here and made no additional changes)

Velo au natural
#39
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Joined: Oct 2009
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Looks like it is near enough to start riding and see how you like it on the road.
Quite an upright riding position, but that is just personal preference.
I would rotate the bars down a bit though. Not the levers so much, just the bars.
Quite an upright riding position, but that is just personal preference.
I would rotate the bars down a bit though. Not the levers so much, just the bars.





