I am 6'2" tall & have a Silvio with just over 500 mi on it. The seat back on the Silvio is the same stamping used on the other Cruzbikes & in the kit. The seat back angle is fixed at 45 degrees due to the structure. Unfortunately, the narrow seat top neck hits me right in between the shoulder blades. On one fairly long ride (~35mi) with a stiff headwind, I developed an annoying stiff neck & shoulder blade pain which I attributed to nerve pinching in the shoulder blade area. I had been pushing quite hard and simultaneously trying to recline my neck to get a more "aero" position.
My experimental solution was to extend the seat back a bit higher to keep my shoulder blades supported. I usied a couple of thin sheets of 8-1/2" x 11" aluminum (letter-sized paper) I had laying around. The combined thickness of the 2 sheets was about (.065"). Since there are two independent sheets, they both bend with a reasonable pressure. I thought about using a single thicker piece in the .090 - .125" range, but it seemed too stiff.
These are mounted in front of the seat back (but in back of the padding) using the top set of mounting holes already drilled in the seat back (used to mount the seat rail interface in the kits, but unused on the Silvio). This provides about a 6" extension beyond the seat back. I put a chunk of thin carpet pad as a cushion for my shoulders and covered the assemblage with a spandex leg of one of my old cycling shorts -- not pretty, but functional for a prototype.
So far (about 40 miles on the mod, split into 20 and 25 mile therapy rides [for an ACL replacement 2 weeks ago]), the prototype design seems to do the trick. No shoulder or neck pain at all. However, I seem more "upright" in my riding position, since I can't push my shoulders so far back any more. Further, having the shoulder support plates be somewhat flexible seems to reduce the effects of our Idaho chipseal road surfaces transmitted into my head. Or course, on those rare freshly paved roads without chipseal, the ride is absolutely dreamlike.
In the photos below, you can see the blue annodized plates bolted to the seatback. [For those of you wondering what the white paper is in the seatback cutout, I store my spare inner tube, plastic tire levers & stick-on patches there.] I ended up using a couple of nut plates to fasten the extensions -- these required drilling another set of holes directly above the originals.
My experimental solution was to extend the seat back a bit higher to keep my shoulder blades supported. I usied a couple of thin sheets of 8-1/2" x 11" aluminum (letter-sized paper) I had laying around. The combined thickness of the 2 sheets was about (.065"). Since there are two independent sheets, they both bend with a reasonable pressure. I thought about using a single thicker piece in the .090 - .125" range, but it seemed too stiff.
These are mounted in front of the seat back (but in back of the padding) using the top set of mounting holes already drilled in the seat back (used to mount the seat rail interface in the kits, but unused on the Silvio). This provides about a 6" extension beyond the seat back. I put a chunk of thin carpet pad as a cushion for my shoulders and covered the assemblage with a spandex leg of one of my old cycling shorts -- not pretty, but functional for a prototype.
So far (about 40 miles on the mod, split into 20 and 25 mile therapy rides [for an ACL replacement 2 weeks ago]), the prototype design seems to do the trick. No shoulder or neck pain at all. However, I seem more "upright" in my riding position, since I can't push my shoulders so far back any more. Further, having the shoulder support plates be somewhat flexible seems to reduce the effects of our Idaho chipseal road surfaces transmitted into my head. Or course, on those rare freshly paved roads without chipseal, the ride is absolutely dreamlike.
In the photos below, you can see the blue annodized plates bolted to the seatback. [For those of you wondering what the white paper is in the seatback cutout, I store my spare inner tube, plastic tire levers & stick-on patches there.] I ended up using a couple of nut plates to fasten the extensions -- these required drilling another set of holes directly above the originals.