Singlespeed & Fixed Gear - Brakeless on a radial rear wheel?

http://www.fixedgeargallery.com/2005/june/LoggiabikeLoggiabike.htm

And he has a 3x front to ruin any aesthetics as well.

"I'll simply say that I've yet to hear an argument against the efficiency of radially laced rears that is based on science, and yet to here an argument regarding their safety based on experience."

All lies and jest, still a man hears what he wants to hear and disregards the rest. - Paul Simon

Dumbass.

"yet to here an argument regarding their safety based on experience."

That's because nobody else is dumb enough to do this. I don't think he's gonna die or whatever, but I do think his hub's in for a thrashing. I've heard more than a few tales of radial fronts cracking up and the rear's only got it worse.

Plus the power transfer has got to be terrible.

Oh, and I think radial is ugly anyhow. :)

What is the lacing method that has the spokes twisting around each other? I like how it looks but I don't know anything about how stable or unstable it makes the wheel.

i can picture that hub turning a whole bunch before the rim catches up. ridiculous!
it would be fun to try riding that thing.

He's got a mtn bike for sale on Craigslist with the same wheel setup:
http://www.craigslist.org/eby/bik/80126417.html

This guy is an idiot, and the fact that he is selling a bike on CL with a radial rear is even more frightening. He is going to sell that bike i bet to some guy who really has no idea what he is buying. The buyer might ride this bike. The rear wheel/hub may fail. He may die/injure himself.

I bet this guy is one of those people that thinks "If I haven't seen it, it doesn't exist." These are also the same people that get weeded out by natural selection

i emailed him regarding his radial rear and he told me it's a myth that you can't lace a rear radially...
well of course you CAN.. but that wheel will be out of true before sundown....

so how bad is a radial wheel for a front wheel?

i wonder if that bike has good chain tension, and how hard it was for him to achieve, or if he was just lucky...

He's got a mtn bike for sale on Craigslist with the same wheel setup:
http://www.craigslist.org/eby/bik/80126417.html


not enough spacers i think..

http://www.loggiabike.com/page1/files/page1-1002-full.jpg

:rolleyes:

The kids love the form. Who cares about function?

whatever happened to "form follows function"?

as the kids say..."I'm 20 years old and invincible." I never ever for any reason want to be back at that point in my life, lol =)

<i>I've heard more than a few tales of radial fronts cracking up and the rear's only got it worse.</i>
any from the past decade that where built with new hubs?? Hubs are much stonger then they used to be.

I like how he has to dish the rear do runing heads out on one side and in on the other. I really want to hear his reason for doing this.

perhaps when he goes down dues to his spokes/hubs failing he'll also take a core sample with his brass bar.
I wish him no ill, but he should not be selling bikes like that,.... bad juju!

any from the past decade that where built with new hubs?? Hubs are much stonger then they used to be.

I can't say much more other than they were, "hey, my radially laced hub has started to crack around the spoke holes." type. I don't know how new or old any of the parts were. On the other hand, do you have any basis for your claim that hubs are stronger than they used to be? I'm truly curious, because I don't know why that would be.

What this radial-lacing dude should really be doing is lacing them up POWerwheel style: http://sheldonbrown.com/power_wheel.html

I'd be much more worried about the fork. Extending a carbon fork 3 inches by sticking crownrace halfway up the steerer is the work of someone who should not be allowed to operate a pencil let alone a wrench.



perhaps when he goes down dues to his spokes/hubs failing he'll also take a core sample with his brass bar.

The person he decided to copy was using a brass bar. His is just plain copper.



So what ever benefits brass has over copper, I ain't gettin' 'em.

I don't know but I would actually do some research and find out before using copper pipe as a handlebar. Considering you can bend copper water pipe over you knee I'm thinking that perhaps brass is a little stronger.

plus copper patina over time so soon it'll be stained then turn green so everytime he rides that bike he's gonna look like he just jerked off an alien.

I'm guessing the spacers below the headtube are because the bike was built for a suspension fork and that's an ordinary rigid fork. Doesn't make it less stupid.

For what it's worth, you can radially lace the non-drive side of a rear wheel. I had that on my road bike (emphasis on had, the hub broke!).

I don't trust rear wheels with radial lacing on the non-drive side, I can only imagine what kind of havok drive side radial lacing will wreak!

You can do that on a dished rear wheel because the non-drive spokes are considerably less tensioned than the drive side. On a dishless single speed wheel this isn't so.

You can do that on a dished rear wheel because the non-drive spokes are considerably less tensioned than the drive side. On a dishless single speed wheel this isn't so.

Ah, didn't know that.

Yup, that's why on a dished wheel broken spokes typically happen on the drive side.

I've heard that some builders use shorter spokes NDS to be able to bring up the tension, but I've had others look at me like an alien for even suggesting such a thing. So beats me, I've only built symmetric wheels.

So anyone actually get a good solid reply from this guy about why he is an idiot? I mean come on. He's trying to sell bikes that are flat out dangerous to people who most likely haven't got a clue.

I really want to know his "scientific" reasons as to why he thinks it's fine to do this, not some "it hasn't failed one me, so it won't fail on you" bullsh1t.

I suspect he's doing it like that because it's easier to build a radial laced wheel than a cross-pattern wheel. Looks like he uses a standard road wheel (which he doesn't build) on the front of his bikes, then builds up a track hub with a radial pattern for the rear.

I suspect he's doing it like that because it's easier to build a radial laced wheel than a cross-pattern wheel. Looks like he uses a standard road wheel (which he doesn't build) on the front of his bikes, then builds up a track hub with a radial pattern for the rear.

I see what you're saying, but is the guy really that dumb? It's not like 3-cross is rocket science.

No, but why deal with all the cross-lacing confusion of building a 3-cross when there's no "scientific evidence" that a radial isn't just as strong? :p

No, but why deal with all the cross-lacing confusion of building a 3-cross when there's no "scientific evidence" that a radial isn't just as strong? :p

I am shaking my fist at you.

I am shaking my fist at you.

Sweet, I'm waving my spokecards at you (they have nowhere to fit now that I'm switching over to radial rear-lacing since it's clearly superior). :p :D

Sweet, I'm waving my spokecards at you (they have nowhere to fit now that I'm switching over to radial rear-lacing since it's clearly superior). :p :D

Once again, I'm forced to do everyone's thinking. You want to thread your spoke through the spoke card as you're lacing the wheel up. Two holes in the card should do it. Just think 'safety pin'.

Or maybe, with all the weight you'll save due to those shorter spokes, you can just hose the whole wheel down with spray fixative.

I used to work in state police dispatch. The cops usually do a lot of truck inspections over night when not much else is going on, and you would be surprised at the amount of semi's that are put out of service for multiple violations such as bad brakes, suspension, lighting, securing of the load, etc. I'm talking 75,000 pound machines on public highways here. I guess my point is that people are doing worse things out there than radial-lacing their rear wheels.. Either way this guy doesn't have a reason to stop until his wheel breaks, and if it never does than he will just continue to think he is correct..

You can do that on a dished rear wheel because the non-drive spokes are considerably less tensioned than the drive side. On a dishless single speed wheel this isn't so.
I don't wanna start a "well I saw this and it worked thread" with you, but mr. strangers racing (craig roth) runs a radial NDS rear on his brakeless fuji track pro, and Boston bikes has some track wheels built up NDS rear.
There are people out there who do this, but durability is probably compromised.

Does anyone have an actual engineering response to why radial lacing a rear wheel is a bad idea? I've got a scientific education, so feel free to throw the technical terminology and details out, if you've got them.

I'm no mechanical engineer, but I can seem to build up reasons in my mind why its both OK to radially lace a rear, and why its not OK. I can prove myself right and wrong, which is why I need an engineer to explain it further.

I do have radial front wheels, but not because I think they are better in any great way, just because I like the look of radial wheels. I do my rears 3x, but just because that seems to be the accepted standard for strong and reliable.

peace,
sam

Well I can't speek to Craig's radial NDS, but that's what's always been relayed to me. If you think that's cool, I know of this guy who laces the entire rear radial. Cool, huh?

As to your question, phidauex, the problem is that typical cross laced wheels provide tangential loading on the hub flange. This allows the spoke length to act as a spring to absorb some of the impact energy. Additionally, the spoke crossings allow the spoke connected to the load point to translate some of that energy to unloaded spokes, spreading the force across multiple spoke holes.

The failure mode for radially laced wheels is broken hub flanges at the spoke hole.

Well I can't speek to Craig's radial NDS, but that's what's always been relayed to me. If you think that's cool, I know of this guy who laces the entire rear radial. Cool, huh?
I guess it's cool if your into that kinda thing.

My suicide 27" horribly out of true wheel is cool.

the weirdest thing about the guy is the way he posts his bikes for sale on craigslist (for really expensive, and beautifully photographed in what looks like a caribbean hotel corridor) and does the big sell; and then I see them on FGG and he talks about them as if each one were his ever-lovin' first born. so? which one is it? or is he just putting them on CL to "gauge the interest" like the Oakland/NY ebay seller with the $2400 all-black-ultimate-trackstand bike? what is with these people? (um, flings up arms in gesture of exasperation)

well maybe i don't know that much about wheel building... but my friend laced a radial rear and it made the most god awful noise when he went into a skid as his spokes twisted and then reverted back into position... that's why i think it's a bad idea, but like i said i dont know everything.... here is his response to my email when i asked him about the safety of his bicycle.

am replying to you both at the same time, because your criticisms are
> nearly identical.
>
> The common mythology is that a radially laced rear wheel must "wind-up"
> under hard pedaling, much like the tires on a dragster when viewed in slow
> motion, and this may, to use the absolute measures of physics, be true. But
> let me assure you that in practice there is NO discernable acceleration lag
> in a full radial drive fixed gear wheel. That is a myth long held as fact
> by those to whom having an opinion is more important than testing a theory.
>
> As far as skidding goes: A well built wheel will not exhibit the deformation
> that you observed. A poorly built wheel - radial or cross laced - will. If
> skidding is important to you then I'd suggest putting your experience to the
> repeatability test by building, or having someone build you, a few sound
> wheels and testing them under various gearings. I personally ride a gear
> length of 5.25meters on my smallest geared bike, which is much too large to
> do a skid stop without seriously injuring a knee, ankle or hip joint.
>
> As I pointed out to you once before, Yakofdoom, even Jobst Brandt confirms
> that the radially laced wheel is more efficient than the
> leading-spoke/trailing-spoke designs, since as common sense would tell you,
> leading spokes compress under pedaling, thereby dissipating torsional
> energy. A radially laced rear wheel is stiffer and more torsionally rigid
> than a typical cross laced wheel because there are no trailing spokes - all
> of the spokes are engaged in transmitting the torsional force of pedaling
> from the hub to the rim. As a result of applying the torsional force of
> pedaling across a greater number of spokes the deformation of each spoke
> under load is diminshed, achieving a more efficient pedal stroke. However,
> because the dissipitative action of the leading spoke in a cross lace
> pattern is eliminated in a radial lacing, both the the hub flange and the
> rim bear an increased load.
>
> Brandt's (and Rinard's) essential crticism of the radially laced rear wheel
> on a fixed gear bike is that the increased efficiency of such a build may
> excced the load capacity of a given hub flange. In other words, he's
> arguing that a radially laced rear wheel is too efficient. That's a
> facially specious argument, unless it is based in a materials science
> argument. Since neither Brandt, Rinard, nor anyone else has actually done
> an experiment to determine the stress envelopes of hub flanges, made of
> various materials, under various wheel builds, I reject their theories in
> favor of my own experiments in wheel building and testing. Further,
> imagining that the spokes, rims, and hubs are all made of the same
> materials, design analysis would tend to posit the spokes would be the
> weakest members of a wheel, followed by the rim eyelets, the hub flange
> eyelets, and lastly the hub flange as a whole.
>
> If you look at the market of new low spoke count wheels for time trial
> bikes, pursuit bike etc., you notice the quiet reintroduction of radially
> laced rear wheels. The general principles at work in choosing them for race
> rigs are similar to rationales stated herein. Although, they require a
> higher degree of skill to build, radially laced rear wheels yield distinct
> advantages in lateral stiffness, torsional efficiency, aerodynamic profile,
> and, most significantly, weight.
>
> Ramsey, anyone that has thought through, or worked on, the science of the
> question will tell you that a radially laced rear wheel will perform more
> efficiently than a cross laced wheel of the same # of spokes. They may,
> however, become uncontrollably shrill at the thought of you building one, or
> God forbid, riding one (I mean there are sea monsters out there, and if
> they don't get you you might just ride off of the end of the earth).
>
> I appreciate your interest in the subject, in fact, I am grateful to you
> both for this exchange. I believe that you both have something to gain from
> researching the subject on your own. I'd suggest, again to you Yakofdoom,
> that you read Rinard's lateral stiffness study, and Brandt's wheel building
> book as starting points of reference for critically thinking about the
> matter further.
>
> best to you both
>
> ps - Ramsey, craigslist ads do not require the kind of disclaimer that you
> suggest, because the "as is" limitation of warranty is read into classified
> advertisements by the law. That is in part what is meant by "classified" -
> they are non-merchant class ads; caveat emptor.

blah. blah. blah.

whatever happened to "form follows function"?
Asking this in SS/Fixed where most people (myself included) ride on roads with bikes form of which follows the function of track riding?
Low handlebars and short top tubes making looking ahead uncomfortable, short chainstays making any real climbs impossible from the saddle, headtube angles which do not allow forks to take average road bump stress along blades since they were designed for smooth track surface, breaking method which takes its most praised form when braked (rear :eek: ) wheel is unweighted etc. etc. :rolleyes:

You can do that on a dished rear wheel because the non-drive spokes are considerably less tensioned than the drive side. On a dishless single speed wheel this isn't so.
Additionaly, the hubs which use this lacing (first issue Campy Shamal wheels come to mind) are very narrow in the middle, thus torsion is not really transferred to the non drive side.

Cheers,
v.

" I personally ride a gear length of 5.25meters on my smallest geared bike, which is much too large to do a skid stop without seriously injuring a knee, ankle or hip joint."

Hmmm. I don't ride fixed, but you guys might have a comment or two. 5.25 is under 70 inches.

The drive efficiency argument is interesting, but the bottom line is: sooner or later, but those hub flanges will explode if the spokes are properly tensioned.

Well, he makes a somewhat-valid point about modern wheels using radial lacing, though I think most of those wheels use custom hubs/rims/spokes in a straight-pull config w/ reinforced flanges and the like.

" I personally ride a gear length of 5.25meters on my smallest geared bike, which is much too large to do a skid stop without seriously injuring a knee, ankle or hip joint."

Hmmm. I don't ride fixed, but you guys might have a comment or two. 5.25 is under 70 inches.

The drive efficiency argument is interesting, but the bottom line is: sooner or later, but those hub flanges will explode if the spokes are properly tensioned.

Someone from the East Bay should offer to meet up with him and skid the hell out of his bike to see how it feels. You could tell him that it would help in his "experiments in wheel building and testing", since he doesn't seem to have the legs to bust a skid with his super-high-geared speed-demon-ultra-cool monster-bikes.

" I personally ride a gear length of 5.25meters on my smallest geared bike, which is much too large to do a skid stop without seriously injuring a knee, ankle or hip joint."

Hmmm. I don't ride fixed, but you guys might have a comment or two. 5.25 is under 70 inches.

The drive efficiency argument is interesting, but the bottom line is: sooner or later, but those hub flanges will explode if the spokes are properly tensioned.
5.25 meters = 206 inches... which also seems rather ludicrous...

meters = development = distance travelled w/one pedal rotation
inches = gear inches = effective diameter (or circumference?) of rear wheel

i usually think in gear inches, so i dunno what 5.25 metres is like, but i run a 70" gear and can skid as long as my tyres are fully inflated.

This bike he's selling on Craigslist: http://www.craigslist.org/eby/bik/80016300.html is geared 54x19, assuming 170mm cranks and 700x25 tires that's 75"

This bike he's selling on Craigslist: http://www.craigslist.org/eby/bik/80126417.html is geared 48x20, assuming 165mm cranks and 700x25 tires that's an incredibly weaksauce 63.3", or assuming 165mm cranks and 26x1 tires an even weakersauce (ketchup?) 57.5"

Either way, neither of these bikes should be hard to skid...

If my skinny a$$ can do a decent skid with 88" then he should be embarrased if he can't skid on 75".

He sounds edumacated, I wish they taught me how to spoke like that...no puns intended.

This bike he's selling on Craigslist: http://www.craigslist.org/eby/bik/80016300.html is geared 54x19, assuming 170mm cranks and 700x25 tires that's 75"

This bike he's selling on Craigslist: http://www.craigslist.org/eby/bik/80126417.html is geared 48x20, assuming 165mm cranks and 700x25 tires that's an incredibly weaksauce 63.3", or assuming 165mm cranks and 26x1 tires an even weakersauce (ketchup?) 57.5"

Either way, neither of these bikes should be hard to skid...

Hey now, I run a weaksauce 65" or so, and it's not all that easy to skid my massive 2.1" slick.

edit : just looked at his 'mtb' listing. Man, that thing is sketchy. I wouldn't let my enemies ride it.