Cruzbike v all others

[tallaussiesje]

John Tolhurst should be able

John Tolhurst should be able to do some great testing for wind effects in Perth: its seriously windy.

 

[Jim Gerwing]

More thinking

It may be that gravity is of no assistance to a DF rider. In my mind's eye I saw the DF rider going up a hill mashing down on the pedals with all her mass with gravity recruited. Then I thought how was the body raised? It was the half stroke on the other side. So, alas, you can't get something for nothing. John refers to an adequately supported rider being able to produce similar amounts of power regardless of orientation to gravity. What would constitute adequate support with regard to the vendetta? There are two that have been discussed already: upper body assistance via the handlebars and lumbar stability (although, due to the angle afforded on the v, the purchase is less than optimal as it would be in,say, an upright sitting position). A further possibility occurred to me (and please note that I am not a biomechanical engineer) that a shoulder harness such as employed on Graeme Obree's latest prone bicycle or on the extreme supine recumbents,something like a ram's horn handlebar but fitted for the shoulders. It could also be fashioned of webbing as on sailplanes . Ps Mr Taylor's Critical Mass II goes a long way toward what was merely the germ of my thoughts. I wonder if his spandex gap could be covered by articulating the fore and aft sections. I'll give him a dingle.
Jim

 

[Charles.Plager]

Hi,
There is a technique

Hi,

There is a technique known (at least on BROL) as bridging. One plants the shoulders firmly against the back of the seat and lifts the butt off the seat. This technique requires good core muscles, and since I am lacking in that department, I can only do this for relatively short periods of time. When I do this, I am able to transmit a lot of energy onto the drive wheel and am able to push up short but steep hills much faster (factor of 2) than I can by spinning my way up. (You can read about some of my experiences bridging here which also has some links to BROL). Be aware that since you are wedging your back in place, you are now able to put more pressure on your joints than you generally do when riding and therefore should be more careful about not hurting yourself.

For what it's worth, I believe that the biggest advantage a DF rider has is that when she stands up, she is using a different set of muscles and this switching back and forth keeps her legs more fresh than if she only spun up the hill. On a Cruzbike, you can (poorly) replicate this by alternating between laying in your normal position or pulling yourself as upright as you can. The problem that I have is the latter again requires core muscles, and these seem to fail me when I'm tired and trying to get up some large hill.

Finally, riders like Jim and Maria (and I'm sure others but not me) have a lot of success by slowly mashing their way up the hill where they are using the pedal steer in their favor. The cadence necessary to do this is quite a bit lower than I usually go and I haven't (yet?) had success with this.

Cheers,
Charles

p.s. I have seen recumbents for time trials that have shoulder harnesses built into the seats.

 

[Jim Gerwing]

Mr Traylor

Thanks Charles:
I tried e-mailing Mr Traylor but it comes back undeliverable.
Anyway, I'm at least a year way from starting a project on that scale.
Jim

 

[kidneyboy]

Fairing a V seems

Fairing a V seems problematic. You are already pretty aero so conventional wisdom would be to put a tailfairing on one and clean up the air behind you. A front fairing doesn't make sense unless you clean up the air behind you so that would lead to a full fairing. A full fairing with a very reclined rider inside it makes getting your feet down and back up a big issue. A Silvio may make more sense at that point.
You can see that this could be a long discussion.

There is plenty of aero talk at recumbents.com

 

[Charles.Plager]

Hi Kidney Boy,
I completely

Hi Kidney Boy,

I completely agree that it's not obvious. I'm thinking a full (ish) fairing with a wind wrap - (a la F40). I agree that this will be easier with the more upright Silvio, but I think somebody who knows what they are doing ( i.e., not me), could do something that works pretty well on the V.

Cheers,
Charles