[Closed] Useless cr@p bike part inovations!

Upper dead point? What?

I can only think of biopace, but that had its fans.

eh?? How is that better than a straight crank arm?

Barel uses Rotor Q-rings (think biopace) for DH. But you also have to set your chain device up to 10mm away from the ring to account for its changing diameter. Sounds a bit too much faff to bother with. With my current rubbish skill level and silly-steep DH trails round here I hardly pedal my dh bike anyway!

I have heard that those vibration-daming bar plugs for road bikes are also a bit emperor's new clothes. Any experiences of them?

The best thing about this crank is that it's only 400 grammes heavier than a normal crank - double whammy! doesn't do ought, and heavier, ideal! 😆

It's nice to see the old rubbish ideas being recycled
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i always liked biopace, but then again i have a ruined knee hich probably makes me the archetypal biopace user.

At what point does the designer think that those cranks will work? And why were they not laughed out the door 40 years ago?

I know, even to me it doesn't make any sense, and i'm as thick as pig shit. Bobby Julich used a similar system to biopace for years, didn't do him any harm!

Some blokes used to bend one pedal arm so the pedals wasnt 180 deg/opposite in cycle speedway, rekoned it helped get the 2nd stamp onto the pedal going into the first corner...

Crap innovations/re hashed ideas gotta be girvin forks, much like a 1920s Vincent mororcycles forks.

Mind you I quite like the look of USE SUB forks and thats just another re hash on a leading link suspension design again from motorcycles of the 1950's re hashed again in the 70's for a bit and still used in sidecar MX because of the anti diving properties under braking.

Doesn't Sastre use oval rings?

nickc - Member

Doesn't Sastre use oval rings?

Yup! Sponsored by Rotor.

my mate has one of those fancy mtb chainsets with rotor rings he says he cant tell any difference . but hes paid to use it so he doesnt care. lucky get lol

how about something that converts decades of finely honed bicycle transmission technology into something from the 1930's

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Sauser uses Rotor rings too.

I present to you, my shimano airlines...
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ahh, airlines. fantastic. saw the thread title and that was the first thing popped into my head.

chainstay mounted u-brakes.

There was, in the dim and distant past, a product bought to the market that looked for all the world like a robust plastic coat hanger with the 'hanger' part removed. You bolted said product to the BB shell, and it help grind the bike over logs and other other trail objects "allegedly" needless to say it was utterly utterly pointless. Came out about the same time as things like Crud Claws and DCDs and mech tensioners.

the girvin design is actualy a very good one.

Bearings not bushings, easy to DIY service

Stiffer and lighter, like the logic behind VPP/DW/Maestro compared to horst links, faux bar's and Single pivots. Link two stiff structures together by two short stiff links rather than try and build one larger stiff structure.

Control over axel path, either to make it anti dive like USE or make it more supple like the whyte forks.

Control over axel path, either to make it anti dive like USE or make it more supple like the whyte forks.

anti-dive used to be a big thing to fork designers. I always thought that the girvins would get more acceptance than they did, but I guess people liked/were too used to the behaviour of telescopic forks, and with the advent of longer travel folks felt (rightly or wrongly) that there was a need for compression under braking to speed up the turning response, and that variable compression damping gave them the control they needed.

Every few years someone comes along trying to "revolutionise" cranks/pedalling - BioPace, Rotor, that Taiwanese stuff ^^ and it's always crap...

You'd have thought they'd learnt that by now.

I cannot see how that crank achieves anything at all. But I'm not an engineer, so this [i]may[/i] be me being dense. 🙂

i cant believe it!

20 posts on a thread about useless bike parts and no ones mentioned a certain component retailer in any form.

STW is losing its touch.

good to see DMR made an appearance tho. their speed guide needs to be on this list too.

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It doesn't get much weirder than this ...

http://www.powercranks.com/videopages/videomtdiablofun.html

check the video

good to see DMR made an appearance tho. their speed guide needs to be on this list too.

How exactly is the speed guide useless? I've ran one since 1999 and never lost the chain! With a bit of care to get it set up right when first fitting it runs effectively and silently. Much prefer it over an MRP style device, which wouldn't fit my set up anyway due to a BMX crank/sprocket!

A certain Mr Wiggins has been using rotor rings in the the TdF. They are noticeable even on crappy resolution live feeds, setting up the front mech must be a nightmare!

Biopace was a crap implementation of oval rings (90 degrees out) which are being very widely used by pros (particularly roadies) these days. Not a crap idea at all.

bruno says 29ers are so 2006 ...

36ers are hawt !
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the rowbike!

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Although I like it 😀
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so does anyone use rotor chainrings who isn't paid to?

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front mech setup isnt too bad, you just set ipt up for the largest diameter and thats that, roadie mechs can be trimmed anyway, so you just overshift and click back a couple of clicks if it wont go.

The shifting gates are in the low power bit anyway so your actualy helping the chain along in a way.

girvin flexstems were diabolical, and farcically expensive. Felt like your bars had snapped. And the superior Softride stem cost more than a set of forks and still felt like broken bars..

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Julianwilson said
>I have heard that those vibration-daming bar plugs for road bikes are also a bit emperor's new clothes. Any experiences of them?

Not a roadie so not sure specifically what youre referring to, but bar end weights can be crucial to damping out vibrations in motorcycle handlebars (which I appreciate are a different kettle of fish, with all manner of different frequencies of vibration to deal with).

That powercrank vid - what the hell is "no cheatinG" out of the saddle climbing?!

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Although I suppose the hat's useful enough...

The guy who used to own the Strawbury Duck at Entwistle sunk a load of cash into the production of a plastic handle which attached to the bottom of the seat tube to make it easier for the bike to be carried over gates / fences. 😆

I had a flexstem for ages, plus several layers of drop bar tape on Brahma bars. Was ok for something like SDW, when you're just riding along and it is difficult to get your weight completely off the bars. As soon as you start riding on your feet and not your hands (downhill) it gets a bit pointless.

What is currently considered cool and will be laughed at five/ten years hence? Remote control droppy seatpost? Remote fork lockout? Super-slack head angles? Six inch travel for normal bike? Or will they all still be with us?

those cranks work, science says so:

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fibonacci seems to work for nature and that's been working on it a lot longer than we have

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Approximate and true golden spirals. The green spiral is made from quarter-circles tangent to the interior of each square, while the red spiral is a Golden Spiral, a special type of logarithmic spiral. Overlapping portions appear yellow. The length of the side of a larger square to the next smaller square is in the golden ratio.

MRMW - for a luddite like me, can you please explain (in the manner one would to a 5 year old) how a force from top dead centre through the BB axle centre can give rise to a resultant rotational force with funky cranks?

i want a 36er, they are indeed "hawt"

i have absolutely no idea. but there's a formula for you:

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science says so

What utter mumbo-jumbo

Until the Vatican approve them I don't see how "science" knows better, do you?! 😡

i suspect although it's difficult to tell from the pics that the rings are not centred on the axis of the axle.

The cranks on handles to wind-up wells are shaped like that - I guess they lose less to bending.

actually forget that, it clearly is centred

As far as I can tell, what those test results are showing you is that the crank flexes. Because of the shape of the curve, it will turn the chainrings slightly due to flex when pushed straight down.

Strange how the graph only shows results for 0 to 60 degrees. I wonder what happens around the rest of the rotation - for instance at 180 degrees?

at 180 degrees theres no force is there?

i guess that depends very much on how smooth a pedaller you are. there will be a point where there is no force but it is only momentary. at this point the other crank will be (hopefully) applying more force due to the flex characteristics.

i might order some now 😆

at 180 degrees theres no force is there?

29ers......singlespeeds we don't live in the dark ages.....flatties great is you want to fall over in the mud,lose 50% effiecientcy,and look like a american skater boy....coil shocks.heavy and crap...tubes....why not tubeless?....baggies...just plain silly.

rant over calm........

flatties great is you want to fall over in the mud,lose 50% effiecientcy

😯

good rant

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Why would flatties make you fall over in the mud?

bikerbruce reads MBR...

flat pedals lose about 15%-20% efficiency depending on the rider/shoe/pedal combination.

Given that the average ride isn't done at 100%, the disparity between fittesdt and least fit on a ride is probably massively more, tire choice probably makes a bigger difference, and im not racing its hardly a big deal?

And anyone who thinks they pedal perfect circles is sadly deluded, if you're sat in the saddle your still putting weight on your back foot. So the not "pulling up" only actualy loses you about 5%, the rest is through squidgey soles and crank/pedal flex.

The not pulling up loses you nothing at all, since at best you only unweight the back foot slightly. What loses you more is having to recruit extra muscles to keep your foot in place.

flat pedals lose about 15%-20% efficiency depending on the rider/shoe/pedal combination.

evidence, or just hand waving?

look you get the gist of what i'm saying......if you have carbon soled shoes with uberstiff soles then all is good.
thisisnotaspoon ...dont get me started on tyres ;).
flatties rely on a flat sole to grip the pedal...so confuisus shoes with no grip maketh a man fall over in mud.
Bruce

I love internet 'truth'

[i]flatties rely on a flat sole to grip the pedal...so confuisus shoes with no grip maketh a man fall over in mud.[/i]

they also have pins - cant say i've ever had a real problem.

flatties are superb in the mud - much better than SPD's when its really claggy 🙂

The not pulling up loses you nothing at all, since at best you only unweight the back foot slightly

Curious, not sure how I manage to pull my shoe out of the cleat on steep bits by slightly unweighting my foot!

It's hilarious that people genuinely believe that pulling up "saves" energy and the belief that pulling up doesn;t in itself use energy. Having flatties and NOT pulling up saves more energy ffs..

Curious, not sure how I manage to pull my shoe out of the cleat on steep bits by slightly unweighting my foot!

Enfit - the pulling up uses different muscles. Not that it does not use energy but you are using more of the total muscle mass to provide thrust. Hence greater efficiency.

Only a minor effect tho for sure

Not pulling up does not save energy, because your trailing leg weighs quite a lot, and if you fail to lift it your front leg has to do that.

Because you're not pedalling efficiently.

What has efficiency got to do with it? How is it possible to pull your foot out of the pedal cleats if you are not pulling up on the pedals?

What has efficiency got to do with it?

Just resurecting it for an argument on a friday.

My masters dissertation was on putting sensors in sports gear so I read arround this stuff.

In summary-
Pedaling 'perfect circles' is more about keeping the tension in the chain as constant as possible, than actualy pulling up as hard as you push down.

Just try it, attach a 25kg weight to your foot (a 25kg sack of spuds maybe?) and try and lift that leg up as if your were pedaling.

A sprinter can put down arround 8x that force (arround 200kg per leg)!

If you could pedal a perfect circle you would detatch your lower leg from your upper leg with the strain on the ligaments.

SPD's are more efficient, but only 20% ish, 10-15% of that is down to shoe design, if you put 5.10 rubber on a set of SPD shoes you get back most of that loss. the remaining 5% is in lifting the dead weight of your foot, shoe and leg. But in most situations SPD riders are doing just the same and not pulling up.

Anyone on a tandem? If you try and ride with the pedals in phase and the second person is significanlty weaker than the other, they feel like the pedals are falling away from them, this is what your back leg experiences when you try and pedal perfect cicrcles, at best it barely adds anything to the torque, normaly it just lifts a fraction if its own weight.

n.b. those figures were based on running shoes which are soft and squidgy.

A stiff BMX shoe will be much closer to the hypothetical 5.10/cycling shoe combo.

since you resurected it and i'm in a taiwan hotel at the mo, the daftest thing i've seen this week are those stepper bikes. again. every f-in trade show you get people 'cruising' the aisles (ie as popular as riding your bike on a busy pavement at rush hour!) on bikes that use up-down motion steppers with a sprung ratchet chain to crank the wheel 🙂 kind of fun in a way but someone's really trying to sell them, still.

someone must have deep pockes to promote them cos show space isn't cheap and i've seen them at shows since year dot, but i've never seen one being used outside a show hall.

optimism can be both wonderful and a bit sad ) anyone ever seen one that may have been bought for real £??

v interesting spoon.

I think 5.10s w/the thinner flats are getting pretty good now. I'm interested in how getting your foot closer to axis of axle improves things, some SPDs are worse now I think.

What you say about pulling up you leg/foot is interesting.
I guess you can create a lot more force from your quads than your hamstrings, so maybe it's better to just use those.

spoon, how about on a fixed wheel, or even accelerating while spinning a fast cadence? that seems to work better when spinning cirles as much as you can. but interesting point about the downforce vs lifting the spuds, got me thinking..

if we could spin near-perfect circles we wouldn't need anti-squat in FS designs right?

Those Powercranks are brilliant for use as a training aid if one leg weaker through injury or disability or you are a professional sack racer and even if you just want to look like cock and have kids throw sticks at you !

For all the efficiency you may gain going up with SPD's if you then feel less comfortable going down (which is often cited by people as a reason for not using SPDs) and therefore go slower on the downhill section, over the whole ride it's not going to gain you any time/speed...personal choice imho.

Off topic though! 😉

Have we done Scott oilers yet?

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Fixed gear doesn't make a difference, anyone should be able to pedal so theres always at least some tension in the chain.

IIRC the faster the cadence the less you pull up.

eg.
Stood up sprinting you pull up quite a bit. Which is where SPD's win.

Sat down your somehwere in between, your just about unweighting your leg, SPD's are of some but marginal benifit here.

Spinning at 120rpm+ most subjects were still pushing down well into the upstroke (i.e. past BDC), the downward force on the pedal was greater than what youd expect from just accelerating the weight of the leg.

I'm racking my brain/google trying to find the paper.