ok, so now, lets make a fast one

[John Tolhurst]

A little while ago we started talking to a professional athlete about going for some record attempts on our bikes. We got him through a back strain last year that threatened his training by having him use a Sofrider.

In recent discussion over at BROL people were critisizing the Silvio's 45 degree seat back angle as not being good for speed and I had to point out that I did not design the Silvio only for speed, there were other considerations. Ride quality, long distance comfort, mixing in traffic, overall build quality, and so on. Bryan assessed the Silvio as being in the elite for its climbing ability, despite being a dual suspension bike.

But now it is time to think, what would a cruzbike look like if we loosened up on the above objectives and focussed only on aero and power delivery. Sure, it won't have the qualities of the Silvio - it will have its own charter and character. So I deleted suspension from the specification and lowered the seat to 473mm, reclined the back more, worked more on the stiffness of the front structure further. I am retaining the 700c wheels and road bike compatability, as that is the equipment used by riders we should target. I am keeping a wheelbase of 1020mm which is about an inch over a road bike and two inches over a track bike. I dropped the height of the handlebar clamp to allow for foldable handlebars. I kept the build to alloy for cost and production reasons, knowing that anything we do will only be better when committed to carbon fiber.

I plan to make two of these. If you are a world class cyclist winning races, then you may wish to work with Cruzbike on taking some of the hpv world records. Its time to rumble folks, and I mean that in the nicest way!

The shaded element is thin plate.

 

[Mark B]

The word that comes immediately to mind is; DROOL!

Can't wait to see the bikes!

Mark

 

[trapdoor2]

Ah...now we're talkin! So, in an appeal to the weight weenie in all of us, what is the target weight? I assume you're designing for the typical Cat 3 rider, who typically masses around 65kg... I'll never be able to get on one...but if you're going to go racing, go all the way!

 

[teacherbill]

If you are a world class cyclist winning races, then you may wish to work with Cruzbike on taking some of the hpv world records. Its time to rumble folks, and I mean that in the nicest way! [/QUOTE]

John,
Can I volunteer to become a world class athlete? It make take a bit since I am 58, but I am willing to try :mrgreen:
Bill

 

[Peder Torgersen]

I hope to do some racing this season! But you need someone younger and faster then me.
But seriously there are people like me that enter races that know they will not win but have a chance of completing and perhaps being faster then last year?
I hope you get a good qualified rider and there may be a marked for riders on different fitness levels that want to ride fast, in comfort and something that resembles a road bike!


Peder

 

[Mark B]

Seriously..... I would make a run at this if I were younger. And slimmer. And faster.

:lol: :lol: :lol:

Mark

 

[trapdoor2]

Just some 'thinking out loud'...

If you only plan on making two...and the target market is "world class racer types"...why not wait to build until you have a body to measure for fit and then delete all the "adjustability". No need for a joint in the TFT, no need for pivots at the fork ends or BB ends (no suspension). You could make the front fork/triangle all one piece and devise a clamshell mount for headset bearings.

Certainly the rear triangle gets really light, without a drive wheel, one can delete all the strength needed to react forces from the drive chain, etc. Might be a perfect place for a very light fork of some kind (even a mono)...no need for a rear "triangle" at all, really. All you want is to hold the wheel in place and provlde somewhere for the braking forces to go...

And go find a local Cat 3 racer, a young buck with an open mind and legs of spring steel. You don't need official TDF meat, just some really fast local kid who will jump at the chance to go faster!

 

[Mark B]

trapdoor2 wrote: Just some 'thinking out loud'...

If you only plan on making two...and the target market is "world class racer types"...why not wait to build until you have a body to measure for fit and then delete all the "adjustability". No need for a joint in the TFT, no need for pivots at the fork ends or BB ends (no suspension). You could make the front fork/triangle all one piece and devise a clamshell mount for headset bearings.

Certainly the rear triangle gets really light, without a drive wheel, one can delete all the strength needed to react forces from the drive chain, etc. Might be a perfect place for a very light fork of some kind (even a mono)...no need for a rear "triangle" at all, really. All you want is to hold the wheel in place and provlde somewhere for the braking forces to go...

And go find a local Cat 3 racer, a young buck with an open mind and legs of spring steel. You don't need official TDF meat, just some really fast local kid who will jump at the chance to go faster!

+1

I keep thinking about buying some supplies and figuring out the carbon fiber process. Start out making some small parts, then move into some bigger parts, then do just what you describe with the front end of my Silvio.

It's always been in the back of my mind that the Silvio is basically modular. You have the main frame, which aside from stripping all the filler out ala VeloLev (speaking of which, he has been oddly absent) there really isn't much you can do. But the rear end... I want to believe you could make interchangable rear sections. Maybe a longer wheelbased section with an intergrated rack for touring... A solid CF bolt on unit for hauling butt and the stock unit for all purpose speed and comfort. The front end is where the major weight cutting comes just as you describe, made to fit full on carbon fiber for balls out speed.

Don't get me wrong, the Silvio is a really fun bike, just as it is. But a transformer bike would be neat, too. Instead of having a bike for going fast and a seperate bike for touring and a seperate bike yet for commuting, why not a bike that does it all, just by changing out a few odds and ends of parts?

Oh well, a guy can dream, can't he?

Mark

 

[trapdoor2]

The trouble with "transformers" is that you have to add weight by creating fittings (so you can add/remove parts). While I agree that it can be done, I would not recommend it for the "Cruzbike Rocket". In my mind, I would target something within UCI size and weight restrictions (185cm overall length, minimum mass 6.8kg...the rest of the dimensional restrictions to be dismissed). A ~15lb recumbent of any sort will raise a lot of eyebrows and generate a huge level of interest, regardless of design. Hit that one little weight target and all those MBB naysayers will be diving off of cliffs to get one.

Of course, there is the new all CF MBB "low racer" out there (which looks really sexy), but I'm not all that thrilled about being down so low...even though I ride (and enjoy) a Baron. I like where John is going with this concept and am excited to see how it pans out. What I don't want to hear (from the peanut gallery) is an excuse laden pile of stinking controversy. John designed the original Silvio to "fit" into the DF rider's mindset of componentry...do the same with the DF rider's racing regulations (at least those with which a recumbent can comply), design it to fit, they will bring $$$$$!

 

[Mark B]

trapdoor2 wrote: The trouble with "transformers" is that you have to add weight by creating fittings (so you can add/remove parts). While I agree that it can be done, I would not recommend it for the "Cruzbike Rocket".

I agree and I should have mentioned more clearly that I was hijacking the thread away from John's new concept and daydreaming about the current Silvio offering. FWIW, the Silvio already has the ability to accept alternate front and rear ends, IMHO. They just need to be built!

trapdoor2 wrote: In my mind, I would target something within UCI size and weight restrictions (185cm overall length, minimum mass 6.8kg...the rest of the dimensional restrictions to be dismissed). A ~15lb recumbent of any sort will raise a lot of eyebrows and generate a huge level of interest, regardless of design. Hit that one little weight target and all those MBB naysayers will be diving off of cliffs to get one.

Again, I agree, but I'm not so sure about the jumping off cliffs part. It might raise some eyebrows among the naysayer crowd, but they have some serious amount of crow to eat before we get to the jumping off cliffs part, and that will take race wins and records with no room for "yeah buts".

trapdoor2 wrote: I like where John is going with this concept and am excited to see how it pans out. What I don't want to hear (from the peanut gallery) is an excuse laden pile of stinking controversy. John designed the original Silvio to "fit" into the DF rider's mindset of componentry...do the same with the DF rider's racing regulations (at least those with which a recumbent can comply), design it to fit, they will bring $$$$$!

I think you're right again and I hope it happens soon. There's some noses I'd like to rub in that.

Mark

 

[trapdoor2]

Yeah, perhaps "diving off cliffs" was a bit hyperbolic. :lol:

But seriously, if the bike can be designed to meet a "DF standard" set of requirements, those 'complaints' can be erased (or mitigated) and your average rider starts to see the playing field as 'more level'. The BROL trolls won't change their minds, they'll just find another aspect to go molecular on. However, if you can claim a record...or even push close to one, things start to change. Racing and record-setting have always been touchstones...time for Cruzbike to go gold.

BTW, I'm not so sure the UCI length rule (185cm) can be met by a recumbent. The MBB puts too much out front to meet the true std. However, meeting the 'spirit' by using the std. wheelbase suits me fine.

 

[JonB]

trapdoor2 wrote: BTW, I'm not so sure the UCI length rule (185cm) can be met by a recumbent. The MBB puts too much out front to meet the true std. However, meeting the 'spirit' by using the std. wheelbase suits me fine.

I think the 185 cm can be done. Just use a shorter wheelbase and/or smaller wheels ;-)

 

[JonB]

trapdoor2 wrote: The trouble with "transformers" is that you have to add weight by creating fittings (so you can add/remove parts). While I agree that it can be done, I would not recommend it for the "Cruzbike Rocket". In my mind, I would target something within UCI size and weight restrictions (185cm overall length, minimum mass 6.8kg...the rest of the dimensional restrictions to be dismissed). A ~15lb recumbent of any sort will raise a lot of eyebrows and generate a huge level of interest, regardless of design. Hit that one little weight target and all those MBB naysayers will be diving off of cliffs to get one.

Dismiss the minimum weight too, you can always put on weight, so it doesnt matter if the empty bike weighs less than the UCI rules.

 

[VeloLEV]

johntolhurst wrote: A little while ago we started talking to a professional athlete about going for some record attempts on our bikes. <snip>

I love the design John! I echo Mark's sentiment that I eagerly await photos of the completed bike. How are the bars mounted?

lev

 

[Peder Torgersen]

This boy is only 7 not a racer but a pool player. http://www.sol.no/klipps/video/he_is_only_7_years_old_but_one_of_the_best

The point is there are some people with great skills I hope John T finds a young strong rider I’m sure there is someone that is well qualified.

Peder

 

[Cruzn Trav 1]

I will put some thoughts into being your silvio jet fighter test pilot, me being young super fit and already an experienced silvio rider.

I ride regularly on my silvio with top level road riders and I am always at the front.

I think my silvio is fast enough already.

Don't know if I would do the dirty and ride a newer more attractive model when my faithful silvio has helped me get back to being super fit and lose 20kg in just 6 months.

I am a former State And National long distance swimming champion. I have dodgy shoulders and can no longer swim a lot.
Cycling is my new passion.

I am considering getting into road racing, however I only ride my silvio, and would basically have no one to compete against.

What exactly did you guys have in mind ?

 

[John Tolhurst]

VeloLEV wrote: I love the design John! I echo Mark's sentiment that I eagerly await photos of the completed bike. How are the bars mounted?

lev

We want to use a folding bar design, so I have lowered the bar attachment point. A folding bar will reduce aero enough to add about 5 to 8% at your top end.

The folding bar idea has been extensively developed and tested by Tom Traylor, we will be meeting with him next week in California. Actually, if we can get an hour at the encino velodrome it would be helpful. Anyone know how that could be done?

 

[John Tolhurst]

Cruzn Trav 1 wrote: I will put some thoughts into being your silvio jet fighter test pilot, me being young super fit and already an experienced silvio rider.

I ride regularly on my silvio with top level road riders and I am always at the front.

I think my silvio is fast enough already.

Don't know if I would do the dirty and ride a newer more attractive model when my faithful silvio has helped me get back to being super fit and lose 20kg in just 6 months.

I am a former State And National long distance swimming champion. I have dodgy shoulders and can no longer swim a lot.
Cycling is my new passion.

I am considering getting into road racing, however I only ride my silvio, and would basically have no one to compete against.

What exactly did you guys have in mind ?

Big congrats, Travis on the riding and fitness development. We must do a ride together with Neil and with a few other bent riders. So far, they think I'm a good rider, so you can probably set them straight on that score! :shock:

There are a few records that we think are ripe, especially with young strong riders who take instantly to the dynamics of our bikes. Of course the iconic and world famous record is the hour and there are both UCI and HPV definitions. So of all the various records, this is the one we would most deeply like to have. But it is not the only one. The 200m flying start record, the 1km. These are perfect opportunities for a young strong rider with a bike that accepts the whole body's output so perfectly as the Silvio does and the Silvetta is planned to.

Jim Parker is managing this side of things. My job is merely to produce the fastest bike possible. If things go as planned, we will have a Silvetta in Perth in about 4 months.

 

[JimParker]

Cruzn Trav 1 wrote: I will put some thoughts into being your silvio jet fighter test pilot, me being young super fit and already an experienced silvio rider...

I ride regularly on my silvio with top level road riders and I am always at the front.

I think my silvio is fast enough already.

Don't know if I would do the dirty and ride a newer more attractive model when my faithful silvio has helped me get back to being super fit and lose 20kg in just 6 months.

I am a former State And National long distance swimming champion. I have dodgy shoulders and can no longer swim a lot.
Cycling is my new passion.

I am considering getting into road racing, however I only ride my silvio, and would basically have no one to compete against.

What exactly did you guys have in mind ?

Hi Cruzn,
We have in mind setting a few World Records. You can see a list of available non-faired recumbent world records here:http://www.recumbents.com/wrra/records.asp Take your pick. The tricky part is not only being able to break the time standard, but meeting all the officiating requirements. If you can break any of these records, let me know, and I'll see what I can do to help secure the necessary timing equipment and officials.

As you can see, some of the women's records are open. My wife, Maria, is planning on setting the 12-hour record later this summer. Last weekend we were on a 70 mile Cycle NC ride and she passed almost every male rider on the course (one guy out of about 200 finished ahead of us). It wasn't a race, but it was still a competition (if ya kno' what I mean). My favorite moment came when we passed a paceline of road bikes at 26 mph and one of them shouted out in exasperation "Okay, NOW I believe in recumbents!" I've ridden thousands of miles in large groups of road bike and recumbent riders and I'm quite convinced nothing is faster on real-life roads than a Silvio. Sure, a low-racer on a track may be faster, but they'd be dogmeat in short order in a real highway situation. What a statement it would make if a Silvio could take a record from a low-racer. ...a practical touring bike faster than a "track only" bike. I think its possible with the right rider. Maybe YOU are that rider. Check out that list of records and let me know if any interest you.

Jim Parker, M.D.
Cruzbike CEO and Founder