Frame Geometry
#1
Thread Starter
Senior Member


Joined: Dec 2018
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From: Southeast TX
Bikes: Several
Frame Geometry
I'm about to have surgery to fuse most of my neck (C2-C6) and will need to ride quite a bit more upright than I have been in the past. I have no idea how much flexibility I'll have left until I've healed and gone through quite a bit of PT. I've been avoiding this surgery for a while but it's gotten to the point I'm at a strong risk of damaging my spinal cord at the C3/C4 joint and becoming a quadriplegic. If I can't get comfortable on an off the shelf frame, I can have one made by local framebuilder, Hans Schneider. I normally (in the past now) ride a 52/53CM frame. I have short legs but a long torso, so I had a 120mm stem in my racing days, but it has gotten shorter and higher as the neck issues came about. The long torso may play in my favor as, theoretically, I could possibly fit a larger, sloping downtube frame. However, if a custom build is needed, would it be suggested to use longer chainstays to better center my weight between the wheels?
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My collection: 1947 Ciclo Piave, 1955 Liberia, 1969 Colnago Super, 1972 Legnano Olimpiade Record Specialissima, 1980 Mercian Vincitore, 1983 Gitane Interclub, 1985 Peugeot PGN10, 1985 Eddy Merckx Corsa, 1985 Hood Cycles Lo-pro, 1986 Bianchi Vittoria, 1987 De Rosa Professional, 1989 Vitus 979, 1989 Bianchi Super Leggera, 1990 Bianchi Axis, 1990 Specialized Sirrus, 2001 Colnago Dream B-Stay, 2007 Trek 1000
My collection: 1947 Ciclo Piave, 1955 Liberia, 1969 Colnago Super, 1972 Legnano Olimpiade Record Specialissima, 1980 Mercian Vincitore, 1983 Gitane Interclub, 1985 Peugeot PGN10, 1985 Eddy Merckx Corsa, 1985 Hood Cycles Lo-pro, 1986 Bianchi Vittoria, 1987 De Rosa Professional, 1989 Vitus 979, 1989 Bianchi Super Leggera, 1990 Bianchi Axis, 1990 Specialized Sirrus, 2001 Colnago Dream B-Stay, 2007 Trek 1000
#2
Senior Member


Joined: Jul 2007
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From: South shore, L.I., NY
Bikes: Trek Emonda SL7, Cannondale Topstone, Miyata City Liner, Specialized Chisel, Specialized Epic Evo
Why not wait for the builder to recommend something. As well, stems are pretty cheap, so maybe start with playing around with higher/longer stems and see what that yields. Then there’s also maybe get a recumbent. No need to tilt your head up.
#4
Senior Member
Joined: Mar 2024
Posts: 1,948
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From: San Diego
Bikes: Columbine, Lynskey GR300, Paramount Track Bike, Colnago Super (4), Santana Tandems (1995 & 2007), Gary Fisher Piranha (retired), Bianchi Track Bike, a couple of Honda mountain bikes
I'm about to have surgery to fuse most of my neck (C2-C6) and will need to ride quite a bit more upright than I have been in the past. I have no idea how much flexibility I'll have left until I've healed and gone through quite a bit of PT. I've been avoiding this surgery for a while but it's gotten to the point I'm at a strong risk of damaging my spinal cord at the C3/C4 joint and becoming a quadriplegic. If I can't get comfortable on an off the shelf frame, I can have one made by local framebuilder, Hans Schneider. I normally (in the past now) ride a 52/53CM frame. I have short legs but a long torso, so I had a 120mm stem in my racing days, but it has gotten shorter and higher as the neck issues came about. The long torso may play in my favor as, theoretically, I could possibly fit a larger, sloping downtube frame. However, if a custom build is needed, would it be suggested to use longer chainstays to better center my weight between the wheels?
#5
Thread Starter
Senior Member


Joined: Dec 2018
Posts: 905
Likes: 1,763
From: Southeast TX
Bikes: Several
Thanks for the comments. I guess I just need to wait and see how much flexibility I have left. Even my left/right movement may be curtailed. The doc said to go into this as though my riding days are over, so I’ve been dwelling on it a bit. I’ve been riding 40 years and it’s hard to think about giving it up.
__________________
My collection: 1947 Ciclo Piave, 1955 Liberia, 1969 Colnago Super, 1972 Legnano Olimpiade Record Specialissima, 1980 Mercian Vincitore, 1983 Gitane Interclub, 1985 Peugeot PGN10, 1985 Eddy Merckx Corsa, 1985 Hood Cycles Lo-pro, 1986 Bianchi Vittoria, 1987 De Rosa Professional, 1989 Vitus 979, 1989 Bianchi Super Leggera, 1990 Bianchi Axis, 1990 Specialized Sirrus, 2001 Colnago Dream B-Stay, 2007 Trek 1000
My collection: 1947 Ciclo Piave, 1955 Liberia, 1969 Colnago Super, 1972 Legnano Olimpiade Record Specialissima, 1980 Mercian Vincitore, 1983 Gitane Interclub, 1985 Peugeot PGN10, 1985 Eddy Merckx Corsa, 1985 Hood Cycles Lo-pro, 1986 Bianchi Vittoria, 1987 De Rosa Professional, 1989 Vitus 979, 1989 Bianchi Super Leggera, 1990 Bianchi Axis, 1990 Specialized Sirrus, 2001 Colnago Dream B-Stay, 2007 Trek 1000
#7
I would buy yourself an old used hybrid for cheap and use that for your comeback. They are generally both short and upright, but can take fast road wheels. Riding one for a bit might solidify what works and what doesn't, plus the gearing is low enough to keep you in the saddle if necessary.
#9
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Joined: May 2010
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From: Bastrop Texas
Bikes: Univega, Peu P6, Peu PR-10, Ted Williams, Peu UO-8, Peu UO-18 Mixte, Peu Dolomites
After a bad fall and injury to multiple vertebrae I lost quite a bit of rang of motion in my neck. Not just side to side but up and down too. All my bikes required major adjustments and it was a real project getting a comfortable, usable, set up. You just dont know what is or is not going to work for you. I laugh at the way my bikes are set up now days. For me I had to get my Stem up 5cm, ditch the Drops, and go to Bull Horn bars. And thats just the big stuff. I had to make many minor adjustments along the way. They were small increments of adjustment in my shifters, brakes, seat position, seat, water bottle mount, and helmet. Take it slow. Once you get everything worked out then contact that frame builder.
Wishing you the best of a complete and uncomplicated recovery. Maybe you wont need any adjustments at all.
We do what we need to do to ride...

Just a little funny looking but for me rideable...
Wishing you the best of a complete and uncomplicated recovery. Maybe you wont need any adjustments at all.
We do what we need to do to ride...

Just a little funny looking but for me rideable...
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Last edited by zandoval; 12-07-24 at 11:40 PM.
#10
Senior Member
Joined: Mar 2024
Posts: 1,948
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From: San Diego
Bikes: Columbine, Lynskey GR300, Paramount Track Bike, Colnago Super (4), Santana Tandems (1995 & 2007), Gary Fisher Piranha (retired), Bianchi Track Bike, a couple of Honda mountain bikes
Thanks for the comments. I guess I just need to wait and see how much flexibility I have left. Even my left/right movement may be curtailed. The doc said to go into this as though my riding days are over, so I’ve been dwelling on it a bit. I’ve been riding 40 years and it’s hard to think about giving it up.

Don’t let that comment get you down. I ride with the San Diego chapter of the Challenged Athletes Foundation. It is very surprising and heartwarming to see folks overcome serious physical impairments and keep riding.
#11
framebuilder


Joined: Dec 2009
Posts: 1,781
Likes: 2,691
From: Niles, Michigan
Asking a bunch of custom builders their advice on what bicycle option is best will naturally need to our recommendation to get a custom frame. Trying to adapt some of your racing type of bicycles to fit your latest body is going to lead to a compromised result. You need to find a builder that can make a frame exactly to your new position. Frame design can broadly fall into 2 philosophies. The 1st and most common (and what you are probably most familiar with) is make it as efficient riding as possible and handle well. Unfortunately that works best with the young and fit. The 2nd method - and the one I'd recommend to you - is to get a fitting on some kind of fitting device and find out what position you are now most comfortable being in. The fitting bicycle should hold your preferred seat and handlebars and be able to adjust them until you are as comfortable as possible. The problem with trying to switch out bars and stems on one in your fleet is that your frames may still prevent the best possible position for you. Once your new position is established, the frame can be designed around that new position. What I think you are likely to find is that - if you are going to try and use drop bars - your handlebars will probably be well above your saddle height. That will rotate your seat position back requiring a 70/71º seat angle. It is also quite possible you may require "North Road" style of handlebars like what is used on English 3 speeds. Those will position you much more upright. Bicycles designed around those handlebars require very slack seat angles. My wife and I enjoy riding this kind of bicycle on MUT.
To summarize, 1, get a fitting while perhaps trying out a new saddle and handlebar shape to find where your remade body is most comfortable. 2, Have your framebuider design the frame to match your new found seat, handlebar, pedal position. 3. ride happily until you eventually die.

This style of bicycle is great for more casual upright position riding.

This is my Ukrainian made fixture I use to design a frame around a seat and handlebar position,
To summarize, 1, get a fitting while perhaps trying out a new saddle and handlebar shape to find where your remade body is most comfortable. 2, Have your framebuider design the frame to match your new found seat, handlebar, pedal position. 3. ride happily until you eventually die.

This style of bicycle is great for more casual upright position riding.

This is my Ukrainian made fixture I use to design a frame around a seat and handlebar position,
#12
Senior Member


Joined: May 2010
Posts: 5,591
Likes: 2,460
From: Bastrop Texas
Bikes: Univega, Peu P6, Peu PR-10, Ted Williams, Peu UO-8, Peu UO-18 Mixte, Peu Dolomites
Yep... I am getting there for sure...


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