Silvio 2.0 and 27 Degree Seat Angle

[Charles.Plager]

Hi Lisa,
For what it's worth,

Hi Lisa,

For what it's worth, I can easily imagine that those with back issues wouldn't like to use the technique I do. I do hope that they can get the seat angle up to where you find it comfortable.

Cheers,
Charles

 

[marshall2389]

I ride similar to Charles.  I

I ride similar to Charles. I like to be as reclined as possible on my Quest to go fast, then sit up for tight maneuvers, better visibility, and stopping. The only times I need to sit up are for short term, low speed things were aerodyamics is not important so it really works out nicely.

 

[jorhar]

Suspension seat?

http://www.challengebikes.com/chamsin.php

 

[Ivan]

Suspension seat like that

Suspension seat like that seems like a bad idea. Pedaling hard and pushing back into seat would compress the suspension.

 

[jorhar]

Maybe...

I had before Challenge Mistral and with that I felt that I have to push my back to the seat. With Conversionkit Cruzbike I feel that I don't have to push so hard because I use my hands, too. Anyway, some kind of suspension could make also seat angle changes happen. My neck likes more upright seating position than 27 .

 

[Eric Winn]

Well, on the Vendetta I

Well, on the Vendetta I sometimes need to lift my head about two fingers width off the headrest to be able see better out of my dadgum bifocals...

How about an eccentric cam under the padding and a knob with some way to turn and lock it - sort of like a lumbar support adjustment.

Maybe the old blood pressure cuff trick?

Hmmmm....

 

[Ivan]

Ah...additional suspension

Ah...additional suspension that would give seat angle adjustment for Silvio - that's a great idea. Not likely for me but I see how a lot of people would like that.

 

[noahvale]

Cervical Fusion

To answer the original question, I think the headrest is the solution for neck comfort.
I have 5/6 cervical fusion. My Bacchetta Corsa is reclined to about 25 degrees. I use an Aero Don headrest. I can go all day with no neck problems. Until I added the neck rest, I could not recline the seat to more than about 35 degrees. I plan to order a Silvio 2.0 as soon as I can afford to.

 

[thebean]

Any update on modifications

Any update on modifications to get the seat angle more upright?

 

[BentBierz]

I'm very interested in seat

I'm very interested in seat adjustment mods myself. Just coming off of back surgery I am hoping to creep up on a final seat angle. If it ultimately ends up being the standard setting, great, but my sweet spot may be somewhere else as I work to regain strength and flexibility.

 

[Jeremy S]

Hi, I hope I'm wrong, but I

Hi, I hope I'm wrong, but I don't think this is an easy mod. The seat back and frame are connected with long pieces of velcro. To raise the seat significantly, I think you would need a fairly sturdy wedge, almost as long as the seat back and as wide as the frame tube, with velcro on both sides. The wedge would have to mimic the complex curve of the frame on one side, and the seat on the other. Of course it wouldn't have to be solid, but it would have to be strong enough to support your weight and your pedaling forces. Maybe a series of different thickness horizontal supports would work, with the existing velcro replaced with matching horizontal strips, and some bracing between the supports to keep them from shifting out of place.

After raising the seat, you would probably have to abandon the supplied headrest, or find a way to adjust it too (maybe extra padding would be enough in this case).

Just my thoughts after looking at my frame, I'm sure others with more bike building experience will have better input.

 

[Doug Burton]

Seat Angle

My frame is still in transit, so these are just thoughts I've had around this question, based on design drawings and what I know from the design process.

Considerations:

1. Structural integrity of the seat must be maintained. This means the seat back will likely require a reinforcing attachment.

2. Frame integrity cannot be compromised. This means no drilling of new holes if at all possible, and careful location of any point loads from any added supports.

3. Seat mounting must be laterally and longitudinally stable under load.

4. Headrest must be accommodated. This may involve relocating the headrest to the back of the seat ala previous Vendetta models.

5. With the angle adjustment adaptation in place, the original seat recline angle may not be available.

6. This could easily end up looking like crap, so there are some aesthetic considerations.

7. The range of adjustment would likely have to be minimized to meet these other requirements.

I have some preliminary ideas, but nothing more until I examine the frame.

Cheers,

Doug

 

[Andrew 1973]

my thoughts

I am no expert, but I too have been giving considerable thought to providing adjustability for the Silvio seat angle. I ride a v1.0, so if anything, I would like a more reclined position.

My thought is that the Silvio represents the equivalent of a high performance DF; ride a Silvio for a while and see how content you are to plod along. The bike begs to be pushed hard and the latest iteration represents a step forward in design and technology. It is a performance bike and is appropristely designed. The seat angle mightnot work for everyone, but a more upright position presents a higher drag coefficient and creats a bike that doesn't make best use of what the team at Cruzbike knows. With multiple records and an unbelievable RAAM win, I would have to say they know best.

Many other recumbents in the performance category offer an adjustable seat, and there are many riders who are convinced that they need a more upright position. I believe I could easily adapt to the new posiotion of the v2.0, but I am also fortunate to not have back or neck issues. Undersyaning that some of us do made me wish for two Silvio models; one keeping with the geometry of the past iteration and a high performance version which is the 2.0. I know that it isn't necessarily a smart decision to offer two versions of the same product, and maybe a method of affixing a one-piece hardshell sear might be an option. As Doug mentioned, it would be important to adequately support the seat, which is commonly done using a pivoting brackry and seat struts. The struts would certainly affect aesthetics, and may still provide limited adjustability.

 

[BentBierz]

Personally I am not looking

Personally I am not looking for a huge adjustment range but would hope that there may be a solution to allow some type of reasonable range.

 

[Ivan]

Silvio 2.0's seat back

Silvio 2.0's seat back attaches to the frame with Velcro not multiple bolts. Thus angle adjustment cannot be achieved with simple spacers. I think any plausible solution will require machining specific parts and not "off the shelf" items from the store.

For those with neck problems however, note that the compounding factor is not only seat angle but head rest availability. Anecdotes in this thread illustrate this fact. As the seat angle lowers, increased muscle work on your neck is required to keep your head upright. But with the addition of a supporting head-rest this loading is eliminated. If, like Lisa, you prefer to lie seated and not sit upright when stopping then this loads your neck even less. If you are concerned about the low seat angle, could you simulate this angle WITH a headrest? Place a plank at 27 deg, prop your head up with some books and lie there for 15 min? Or recline your car seat to 27 deg and prop up your head with books (don't try driving though!).

 

[Charles.Plager]

Silvio 2.0's seat back

Silvio 2.0's seat back attaches to the frame with Velcro not multiple bolts. Thus angle adjustment cannot be achieved with simple spacers. I think any plausible solution will require machining specific parts and not "off the shelf" items from the store.

I agree that it wouldn't be completely trivial, but seeing what some people have done with Cruzbike modifications, I don't think it's out of the question for putting something together at home. That being said, it is on the more complicated side.

While not trivial, it does look possible to drill holls in the Silvio frame to anchor something (although, again, not trivial). Personally, I'm envisioning some sort of contoured I-beam (that looks better if the 'I' looks more like a sideways 'H').

I can also imagine replacing the carbon fiber seatback with a metal one which could handle the load itself much better (a la Silvio 1.X).

For those with neck problems however, note that the compounding factor is not only seat angle but head rest availability. Anecdotes in this thread illustrate this fact. As the seat angle lowers, increased muscle work on your neck is required to keep your head upright. But with the addition of a supporting head-rest this loading is eliminated. If, like Lisa, you prefer to lie seated and not sit upright when stopping then this loads your neck even less. If you are concerned about the low seat angle, could you simulate this angle WITH a headrest? Place a plank at 27 deg, prop your head up with some books and lie there for 15 min? Or recline your car seat to 27 deg and prop up your head with books (don't try driving though!).

I'd be careful generalizing too much here. Neck problems/injuries are quite varied and what works very well for one person often works very badly for another. I do agree that many (most?) people with such problems do find headrests work well (although I've heard of many who do not).

 

[pRC]

Heavier, heresy, alternative?

As a recall, earlier versions had the seat welded to the frame as part of the beam structure for strength, but with the Silvio 2.0 there may be a completely different path available. Instead of trying to shim the seat back, why not remove all the OEM seat components and add some simple brackets to attach a carbon fiber seat from another brand? Metabike comes to mind especially, since they have a peak at the front of the seat pan between the legs that would make clearance with the main tube easier.

You would also need a new headrest solution, or not, depending on the final seat angle and your own preference or anatomy.

It would be heavier than the OEM Silvio 2.0 seat because the OEM seat back needs no longitudinal structure since it is in full contact with the frame, just side to side strength (and it is a short beam in that direction).

Since a hard-shell seat (Metabike, etc.) is designed for two-point mounting at the seat pan and mid-back it has to have beam strength for all directions and is heavier. But with some clever mounts it could also be adjustable.

I believe that FRP seats are available for $200, and CF for $350-ish. Weights would be in the 1kg range for FRP, lighter for CF.

Just an idea --

/pRC

 

[Charles.Plager]

@pRC: That's not a bad idea

@pRC: That's not a bad idea at all either.

 

[ak-tux]

The Silvio-2.0 prototype

The Silvio-2.0 prototype whose picture appeared in John's blog had multiple bolts for attaching the seat. That would have been easier to modify. But the final production version does not and uses velcro instead. It therefore looks like it would require quite some work to modify the seat angle at the risk of interfering with the integrity and esthetics of the frame.

If one is willing to weld and repaint then try adding bolt holes like it was on the prototype(shown below) then use some spacers and some plywood fabricated to match the curve of the seat and bolted on.

With all due respect to all those that have neck problems and want to modify the Silvio-2.0 seat angle, if you find the Vendetta and the Silvio-2.0 seat angles too extreme why not opt for a Softrider with 700c wheels or even a Quest?

Alternatively buy a used Silvio 1.5 from some of the current owners who will want to upgrade to the Silvio-2.0.

Just thinking...

The Silvio-2.0 prototype with seat bolt holes shown below. One wishes this was the final but clearly the Velcro simplifies the production and eliminates the extra welding needed for the bolt holes

 

[thebean]

It would be great if you guys

It would be great if you guys can work with Doug to give him solutions!! I would never consider a Softrider. I like the fact that the Silvio can be a racing or recreational bike. Now add a versatile seat angle and it will be a great fit for a lot more people.