Its a road bike, Jim, but not as we know it.
Silvio is the world's only recumbent racing bike that is fully
compatible with a road bike groupset and wheels.
Silvio is a front wheel drive moving bottom bracket recumbent capable
of being fitted with the latest Shimano Durace or Ultegra 10 speed
systems, etc, without modification and with all components working as
they were designed to. Silvio is sold as a frame set only which
includes air suspended front triangle, main frame with integrated seat
and suspended rear triangle.
A prototype Silvio fitted with FSA wheels, carbon crankset, 39-53 and 10 speed
Campagnolo Centaur component set.
The dual suspension fitted to Silvio has a carbon fiber, elastomer
dampened system in the rear and a fusion system in the front,
integrating an adjustable compressed air suspension fork, with a
carbon fiber chainstay suspension yoke in a soon to be patented new
front triangle assembly. The frame is aluminum 7005 T6 and integrates
the seat shells into the structure for added strength and weight
savings.
Seat Back angle is 45 degress and is not adjustable, that is, the seat
shells form an integral, structural part of the rear frame. The main
down tube is a teardrop cross-section.
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Rear travel is 13mm 0.5" by elastomer damping, single rebound
titanium leaf spring and carbon fiber rear chainstay.
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Front travel is 40mm 1.5" by adjustable air head shock and
carbon fiber chainstay.
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Wheelbase 1020mm 40"
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Weight distribution with 70kg (154lb) rider: rear 50% front 50%
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Frameset weight as supplied is 6.5kg / 14lbs, with final weight in the order of 11.5 to 12.5kg. The total weight of the complete bike will ultimately depend on the
components and wheels each person selects.
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The Silvio is designed for a double crankset; if you are tall you may be able to use a triple, but we cannot guarantee. We are preparing an adapter plate to allow a triple and will change this entry when that is ready.
While building a light bike is an objective, it is not the only
objective. It must have dual suspension and must be stiff through the
drive structure, including the seat. We were asked why we are so keen
on suspension, since a road bike without suspension tends to be
lighter, stiffer, less complex, and usually faster. A top 10 reasons
list to use suspension might look like this:
10) its the 21 century, should be no reason to do without it
9) cruzbikes do not suffer pogo - so low stiction suspension systems
work well and decrease rolling resistance
8) the front leg adjustment requires pivots in the triangle and so the
pivots to make suspension work on the front are already there
7) FWD needs to get good traction on the front, suspension helps that by
keeping an even pressure against the road
6) the hard shell seat is solid to promote good power, so this calls for
suspension
5) our Taiwan manufacturing partner has some lovely suspension
technology that we've been able to integrate
4) kudos, to build a light recumbent road bike including dual suspension
3) target segment is pretty surely over 40, should have lost the
anti-suspension machismo nonsense by then
2) better grip on the road, better handling, better passive safety
1) its nice to ride down staircases! (legal note - not actually
recommended)
Removing the suspension would make the bike lighter and give it
slightly increased rolling resistance, a slight reduction in
consistency of traction, and possibly increased rider fatigue.
Teardrop Monotube frame design with structural seat shells.
The specs show that shorter riders end up with a more closed position,
taller riders with a more open position.
In the following video, John Tolhurst, Cruzbike Inc Design Director outlines some of the technical aspects of the Silvio.
The FWD system probably needs a little more closed body angle than
other bents. Also, the heart is perhaps better placed if it is not
below the legs. You may lose some aero that way, but the key to a
quick bike is average speed. If you are 10% faster on the 10 minute
climb, who cares about being 2% slower on the 3 minute descent?
Anecdotal evidence on the Silvio indicates it climbs roughly as well
as a normal upright road bike, and possibly better than a low racer.
It has about the same aero performance as an upright rider who is
contorted into the best non-pedaling aero position they can manage.
The design of the rear of the bike presents very little to the wind,
which has paid off. Having riding characteristics that are somewhat
like a road bike is important, as the Silvio is designed to be ridden
socially in a group with upright road bikes, who share a love of
quality road bike wheels, components and riding experiences.
Handlebars are a personal choice, but a center to center grip spacing
of at least 44cm 17.3" is recommended. In the set up as pictured
below, 2" of handlebar could be removed from either side if preferred.
There are only two things that can change that would affect the
suitability of parts for building your Silvio.
1) some front derailleurs clamp around the tube (clamp ons) and some
bolt into a brazed on lug (braze-ons). Silvio requires the braze-on.
2) there are two main handlebar clamp widths, 25.4/26.0 and 31.8. Silvio
needs the 25.4/26.0."
Please note, Silvio uses the British/ISO 68mm format for the Bottom Bracket, as do most of today's bikes.
Slender, light weight, built for speed.
So beautiful, we understand if you never ride it.
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