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My preliminary highracer plans

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Alan
human power expert

2016 Posts

Posted - 09/03/2006 : 23:30:17

Edited by - Alan on 01/01/2008 08:12:09

alevand
human power supergeek

USA
1277 Posts

Posted - 09/04/2006 : 05:47:20

Maybe a carbon form of this, circa 2000. Note the rotable tracking antenna on the Toyota cab. This bike had a tendency to end up rear wheel first on loose trail surfaces. 27x1 1/4 tires (630x30mm)

http://www.geocities.com/aflevand/HPV/PASS.MPG

C:
Tony Levand

Edited by - alevand on 09/05/2006 05:18:38

Jeff Wills
recumbent guru

764 Posts

Posted - 09/04/2006 : 09:58:57

quote:
Originally posted by Alan

This is my preliminary concept for a highracer modification project I have been thinking about.
<snip>
It has the high style bottom bracket that is popular in Europe and dual 700C wheels that are popular in the US. The seat angle is not laid back and will be good for climbing steep roads in Wisconsin, IL and Indiana and other midwest mountainous regions of the US.

Its not a Hachi but a good start to the recumbent riding with 700Cs. With this bike I can do group rides and mass start race events. There is some minor crank/wheel overlap but I am already use to that with lowracers and have no problems with turning by shifting body weight.

??? MINOR overlap ???

To me it looks like the front tire will run into the chain on *any* slow-speed right turn.

In any case, there's a couple homebuilt carbon highracers around here:
http://homepage.mac.com/john4bho/PhotoAlbum100.html
http://homepage.mac.com/john4bho/PhotoAlbum101.html
John and Robert built their bikes around 650C wheels while Tony's has 700C wheels.

Jeff

Upright Mike
human power supergeek

USA
1854 Posts

Posted - 09/04/2006 : 10:33:32

Alan,
A cliche, but "What's wrong with your picture?"
The only Velocity Spartacus 20-spoke wheelsets that I know of, that you have pictured, come in only 650cc size.
700cc upright rider
650cc Volae rider

Mike Mowett

neve_r_est
recumbent enthusiast

201 Posts

Posted - 09/04/2006 : 15:42:59

"exclusive big wheel race series" ?
Which races would these be?

Highracers do have their advantages, especially when facing open course events(ie saftey)and riding with uprights(better visability, better draft usage). You should try it sometime. They are a really accepting group, friends of mine actually.
O and before you skew my comments, if you were to ride in a group of fast uprights you would find use in drafting more efficiently and not being run over by those 3foot above you.

Standard Speed Theory
Low RR + Small frontal area + More Watts = Fast
Big wheels = lower RR
Low seat height = smaller frontal area
Big wheels + Low seat height = Complications
NC3 = complications
Looks like you are the man for the job.
Good luck.

Respect,
Dennis Grelk

BTW I'm a big fan of the Hachi as well. http://www.kingcycle.co.uk/hpvs/Kingcycle.html

neve_r_est
recumbent enthusiast

201 Posts

Posted - 09/04/2006 : 16:48:45

"now that the bike is up to spec and on the road." LOL you said it yourself!

Complication Theory?

$$$$ + how many hours of pullng your hair out? With the highracers you can pay half as much for a readily available bike, assembled and fully functioning, and race it with good results at any open road event you'd like. I've seen it done. How many competitive Ultralowracers can you say that for? None. Megabuck, builders kit, factory racer, 4 month slow boat from Europe only otherwise.

And face it, if the top highracers were to put up with the BS long enough to compete with us at the HPRA events they would still finish top 5. Watts is watts. TTs are another story, but hey, different tool for a different job. Put Deninger on a highracer and he would still kick both of our butts. If you could only have one bike to race closed course, open road, flat, hilly, commute, run to the store, or just cruise around, I doubt any of us would be hanging out on an ultralowracer of any sort.

I went through this tunnel vision crap with another prominent recumbent racer friend of mine. Now he's become a little more open minded, more supportive to growing our sport highracer or low. No more BS. What is your rhetoric doing?

Upright Mike
human power supergeek

USA
1854 Posts

Posted - 09/04/2006 : 19:52:05

quote:
Originally posted by neve_r_est
BTW I'm a big fan of the Hachi as well. http://www.kingcycle.co.uk/hpvs/Kingcycle.html

I'm also a big fan of the Haichi, though I think I heard a rumor that Rob English wasn't riding his creation anymore because he couldn't see well enough on it. Take a look at the front shots on his website. BTW - it is a dual 650cc bike design, which fits Rob 5'9" tall.

Alan, your design looks good. Dennis - I agree that the highracer is better for drafting and all around use - thats why I got one - a Volae. However, I find its seat stay design way too loose, it feels like the back wheel is always washing out on turns - overall you feel just perched up too high. Plus I converted it from a U-bar to a tiller steering and this design doesn't work for me (my shoulders are rolled uncomfortably forward while putting my elbows behind my torso - my mistake in designing it).

I've thought about some designs for recumbents, and a major consideration is how big of wheel can you fit up front between your legs, plus put the biggest chainring (53t = 8.5" around) far enough forward to prevent tire/chainring overlap in turns.
26x1" (559) wheels = approximately 24.5" diameter
650x23c wheels = approximately 24.75" diameter
700x25c wheels = approximately 26.375" diameter
you would think (26.375 - 24.75" = 1-5/8") is not a lot of added length - but it could definetly be too much, if your legs aren't long enough to reach the bottom bracket from the seat.

Then you think you got figured out, but think again about the gearing. Say you like running your 53tooth chainring with 700c (26.375") wheel. If order to keep the same gearing on a 650c, you need a 56tooth chainring. So while you gained 1-5/8" of inseam lenght with the smaller 650 wheel, you take away 7/16" due to the bigger chainring size, so only have 1-3/16" gained.
53t = 8-5/8" 56t = 9-1/16" 58" = 9.5" 62t = 10"

All chainring sizes and wheel sizes are from my own measurements.

Mike Mowett

neve_r_est
recumbent enthusiast

201 Posts

Posted - 09/05/2006 : 03:30:00

Alan-I agree with Mike, this design looks good. Forward view will be hampered, but you can deal with that as stated. And the front wheel skirt eliminates the painful problem. Only issue I see with it for the TTs is the turn around. You can still turn around on a two lane without actually stopping, dismounting, and turning the NC3 around right? Might cost you some time with the more limited steering design, but maybe not too much of a penalty in a 40K.

Mike-Your right about the squirrelyness on the Volae. The Volaes and T-Bones are both that way in my initial ride impressions. The Bachettas didn't seem to do this, I think the geometry is a little different. I don't care much for U-bars, but on the Highracers they seem to find their place.

alevand
human power supergeek

USA
1277 Posts

Posted - 09/05/2006 : 05:30:29

Alan, watch your inner knee to front quick release hub clearances, it's a pain if the seat and BB's too low.

C:
Tony Levand

alevand
human power supergeek

USA
1277 Posts

Posted - 09/05/2006 : 06:03:17

C:
Tony Levand

Edited by - alevand on 09/05/2006 17:48:11

tom porter
New Member

93 Posts

Posted - 09/05/2006 : 09:44:37

A good lookin' design Alan, you're tempting me to build truly low dual 700c. If I can just find the CF cloth. I'd build this using a foam inner structure to form the frame and just have to find a way to desolve the foam when done. My experience with dual 700c is you get a very quick bike, even my fairly high racer was the fastest non faired bike I ever built. Any chain, crank interference issues are not a problem unless you use a very narrow BB spindle. At any speed above 15mph you hardly turn the front wheel any.

O---o

warren
human power expert

2838 Posts

Posted - 09/05/2006 : 13:31:12

And... If you make it FWD you won't have the chainline issues.

SpiderMonkey
New Member

62 Posts

Posted - 09/05/2006 : 15:34:05

I'm convinced.

But it's taken a while. See, I ride both a NoCom and a Volae Team. As much as I like the Team, it's an absolute pig speedwise, compared to the NoCom. I'm talking about 3-4 mph slower under all conditions. Chipseal. Uphill. You name it, the NoCom has it pounded. And I think I've got the miles to justify the feeling. I've ridden them both more than 3K out here in the hills and mountains of Virginia -- which make those little sissy hills in Wisconsin downright funny. I did a metric century the other day on the NoCom and it had 5500 feet of climbing and this was a MILD ride.

Alas, I must be missing something. Everyone says the highwheeler IS faster on the chipseal and on the hills, so I figure it must be true. The math-type in me tends to think that a bit more rolling resistance doesn't amount to a mouthful of spit in the ocean next to the incredible stiffness and aerodynamic advantages a NoCom has over a highracer, but the engineers at Bacchetta say otherwise, so it would be impolite to argue the point.

I can't think of an instance where anyone on a highracer has ever managed to stay with me on my NoCom, and in fact I always pass them, uphill or no, but again, I figure my experience must be abnormal. My legs are as brawny as a 6-month-old chicken's, but they must posess untold power to keep me ahead of the stickbikes. Call it a mystery of the universe, I guess.

So Alan, only one thing remains for you to create the world's most amazing bigwheeel design.

Make it a 29-er.

That's right. Fisher's Website says that Pepperdine engineers found 29-inch wheels were many percentage points faster than 26es, so why go with the puny little wheels they're using on the rest of the stickbikes?

Strap a 29-incher between your legs, Alan, and prove to us you're a REAL man!

Please post an updated design as soon as you get the time.

Larry Lem
recumbent guru

South Sandwich Islands
932 Posts

Posted - 09/05/2006 : 15:59:49

Aren't 29ers the equivalent of 700C for MTB? (Why didn't they call them 700C? Was it just to be different?)

The pictures of Alan's new concept keep looking more and more cool. We are all curious to see the hidden chainline and big wheel between the legs turning radius challenges worked out. There's gotta be a way.

Maybe FWD + shaft drive
But you need a skinny front hub since the legs will be alongside.

Larry Lem

Edited by - Larry Lem on 09/05/2006 16:00:36

SpiderMonkey
New Member

62 Posts

Posted - 09/05/2006 : 18:02:51

Maybe that's right. Who needs a stinkin' 29-er when you can get the grandaddy of all highwheeler wheels working in your favor? I'm talking about the 56- or 54-inch diameter wheels from an authentic boneshaker. Here's the original design, showing that enormous wheel that achieves such amazing, low rolling resistance.

Since these bikes can be purchased for under $6,000 new, that makes them cheaper than a NoCom from the US authorized dealer. They'll also be comparable to a Carbon Aero. We need two, unfortunately, which we'll immediately submit to the sawzall. I believe they can be purchased used for about $3,000, so we'll still be spending an amount comparable to the high-end highwheeler sold by our friends from FLA.

By my calculations, I'll need 20 rolls of CF tape to join and stiffen the frame. That, or I'll need to get better at welding.

Also, please note that, by my calculations, the CF wheel discs pictured here will consume another 10 pounds of CF, a small price to pay, I think, for the increased aerodynamics

Here's a mockup of the final design idea, which I dub: The BoneCom

Lest you think that too large for traveling to the varied and sundry circle race venues across the country, never fear. We can build another, more compact version, the BoneCom Traveler.

There are no chain issues because this is a direct drive system. That'll make the bike a challenge on the hills, but since when have recumbents ever been good climbers?

I'll keep you posted on the build progress as soon as I can shake up a couple of sacrificial bikes.

alevand
human power supergeek

USA
1277 Posts

Posted - 09/05/2006 : 18:38:19

http://www.nashuatelegraph.com/apps/pbcs.dll/article?AID=/20060513/NEWS01/105130134/-1/news

C:
Tony Levand

alevand
human power supergeek

USA
1277 Posts

Posted - 09/06/2006 : 05:22:55

I am glad you gave up, Alan. Now I can build my super bike without competition:

Dished front wheel with single arm. Narrow BB, under seat steering. Drive train totaly enclosed in carbon structure and of course a streamliner fairing would fit nicely over this frame.

C:
Tony Levand

Edited by - alevand on 09/06/2006 05:57:20

Larry Lem
recumbent guru

South Sandwich Islands
932 Posts

Posted - 09/06/2006 : 07:27:40

And with the knees in the way, you'll need a periscope, or a camera, battery, and monitor.

Or you could use the Force.

Larry Lem

alevand
human power supergeek

USA
1277 Posts

Posted - 09/06/2006 : 10:15:30

A pin hole camara projected on a translucent sheet screen or fiber optic glasses

C:
Tony Levand

Edited by - alevand on 09/06/2006 10:18:29

neve_r_est
recumbent enthusiast

201 Posts

Posted - 09/06/2006 : 10:25:05

I think I have been in that liner already. Has a strange resemblence to CCU's Blue Devil at Battle Mountain last year. Add the 700c rear wheel and wha-la....all you need is a loong vehicle to haul it and a team to move it.

alevand
human power supergeek

USA
1277 Posts

Posted - 09/06/2006 : 12:50:02

Yea, but I'm shorter that you are, probably 94 in wheel base.

C:
Tony Levand

SpiderMonkey
New Member

62 Posts

Posted - 09/06/2006 : 17:22:06

Saw some kids riding Unis all the way across Iowa on RAGBRAI two years ago. One had a really huge wheel -- I don't remember if it was that large or not.

If I make a third BoneCom for offroad use, I may use the small, 36-inch wheels. That would keep the bike to a more manageable length of, say, 13 feet.

quote:
Originally posted by alevand

http://www.nashuatelegraph.com/apps/pbcs.dll/article?AID=/20060513/NEWS01/105130134/-1/news

C:
Tony Levand

SpiderMonkey
New Member

62 Posts

Posted - 09/06/2006 : 17:35:39

Looks good but experience on the NoCom tells me you don't want USS. (At least not if you want to maximize speed. If you have other reasons, go for it.)

Here's what I'm saying: I stick my arms out to slow down the NoCom on big hills (and to air out the sweaty pits) and the effect is immediate and pronounced. At high speeds on these lowracers, the low 30s stuff, I've even noticed that simply wearing baggies takes about .7-1 mph off my flat rolling speeds. Keeping small by keeping your arms tucked in front of you really does matter.

(Maybe consider putting a joystick down by your... um... joystick?)

Further evidence, my wife outcoasts me significantly on the NoComs. Same exact bike setup, but subtract at least 20 pounds for her. I should be doing better, but her much narrower shoulder profile makes a major difference. (Same story on the highracers, BTW, but with less of a difference because the speeds are much lower.)

quote:
Originally posted by alevand

under seat steering.

C:
Tony Levand

alevand
human power supergeek

USA
1277 Posts

Posted - 09/06/2006 : 18:30:48

In that case maybe try a tail box on the nocom, it's legal as long as it's glued on.

On a bike this layed back, the arms using USS are almost inline with the shoulders. After riding for half a day, my hands are stiff the next morning with ASS and preying mantis position. I'll probably raise the seat back here so the helmet top is even with the 700cc tire and lower the seat front to the bottom of the fairing, and yes, use remote ASS.

C:
Tony Levand

tom porter
New Member

93 Posts

Posted - 09/09/2006 : 09:54:28

As I am quite a bit taller in the upper torso and 6'4" overall I think may build a wooden mockup over the winter to give this dual 700c lowracer idea a go, why not in our long winters? Yes, Warren I would definitely want to have it be FWD.

O---o

25hz
recumbent guru

973 Posts

Posted - 11/07/2006 : 10:36:47

There is a FWD big wheel low racer out there, the Python:
http://www.python-lowracer.de/projects.html

They run anywhere from 700C down to 16" for the wheels, but the preferred size is 26", and I liked to use smaller rear wheels because there was no point in dragging a big wheel around for either weight or space, IMO. The bikes are fast and smooth, but high speed downhill runs are problematic due to the design and the pros and cons of different pivot angles. I'm sort of a speed freak and the fastest I could manage on a downhill (after about 2000km) was 66kph. And that, was definitely pucker time.

The link above is the project page that shows most of all the pythons that have been built that the designer knows about. You can see by some of the pictures that even with a 26" wheel there is some major wheel leg overlap to deal with. By slowly raising the seat until it allows a couple inches of front wheel deflection to each side for fairly normal riding, it should cause much less leg interference.

The python I rode the most looks much like the image posted earlier:
http://www.fleettrikes.com/python%20final%20mod%20drilled.jpg

The page is here:
http://www.fleettrikes.com/python%20clone.htm

It was a cool bike to build (I built three of them) and a real sense of accomplishment to learn how to ride it, but the major drawback, in my mind, was that the power and the steering were "combined". On a normal bike/bent, even a FWD version, the power is handled by the legs and steering is handled by the arms (for the most part). On a python, the two are joined and can't be separated which is problematic when trying to apply some serious power like on steep hills or sprinting or hard acceleration.

As I'm 6'2" with fairly long legs, I'd still like to try one similar to what is being proposed only it will likely be closer to a "medium" racer due to leg-wheel clearance issues, and won't be a fancy CF version.

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