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PostPosted: Fri Sep 28, 2012 5:34 am 
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This concern about width is overblown.
There is no good physical reason why a narrow cleat pedal system with a stiff soled shoe can't be adequate.
Good old SPDs have small narrow cleats and they work fine. A little bit of rocking is inconsequential.

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PostPosted: Fri Sep 28, 2012 2:32 pm 
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The "silly GIF" is a Gaussian distribution. You see it in many places in nature/engineering. It was brought up to answer the other poster's "Pressure" comment.

thisisatest wrote:
if the cleat/pedal interface is 10cm wide, and there is 1mm of wear at the sides, it would allow for 0.57degrees of roll.
if the cleat/pedal interface is a mere 1mm wide, and there is 1mm of wear at the sides, it would allow for 45degrees of roll.
the load on the edges of the cleat with respect to foot rolling forces would also be 100 times as great as the 10cm pedal/cleat, greatly increasing the wear rate.


This is utter nonsense. 1mm wide interface and 1mm wear, leaves 0 sum, yet you get 45 deg of Roll/Bank for a disconnected system. I don't see where you get the rest of the derivations without saying anything about the kinematics of the system.

I never mentioned anything about "Wear" to unnecessarily complicate the problem, you did! We simply talk about the orientation of the SP cleat to maximize the stability on given pedal. I already said this.

horse wrote:
Bottom line is, as mentioned earlier, when engaged the SP pedal and cleat function as one unit. The rocking sensation you feel is only because the entire unit (in particular the cleat) is not as wide as the shoe.
If you increase the diameter of the pedal, you also have to increase the size of the cleat. But maximum benefit will arise from simply increasing the size/diameter of the cleat. If you keep the cleat the same size but increase the diameter of the pedal (and thereby the shoe having no additional contact with the pedal because of limited cleat size) the system will not be any more stable.


Moving-On..

djconnel wrote:
It would be interesting to test a ball-and-socket cleat to test all of this hot spot theory.

Anyway, I agree pedal quality is more important then weight differences, but I'd personally like to try these anyway.

On float, I don't think I use it when pedaling, but I do like the Speedplay float when I'm coasting to shift my foot around. It may be psychological, however.

Another factor for me is riding in street shoes, which I need to do occasionally. Speedplays work fine for me when I've got reasonably stiff soles. This doesn't look too bad for that, however.


A ball-socket system is less preferable. Because with a flat shoe, the point contact is only at the pole of the ball. Unless the shoe can be made to accommodate a crescent shaped cleat but for all practical purposes the simpler solutions are just more effective.


Hi,

fdegrove wrote:
Hi,

Quote:
im·pulse/ˈimˌpəls/
Noun:
1.A sudden strong urge or desire to act: "an impulse to giggle"; "impulse buying".
2.The tendency to act in this way: "he was a man of impulse".

Synonyms:

impetus - impulsion - urge - stimulus - incentive - spur


Of course feel free to switch from common plain english to the language of physics whenever it suits you but from what I've read so far it's still not clear what the point of all this is other than arguing for argument's sake....

Still, for your information, during the time the impulse occurs whilst pedalling a force is apllied to an area of the pedal. At this area a pressure is then present and distributed over that area.

Since pedals, together with the handlebar and saddle, belong to the three areas that physically support the rider of the bike the pressure on the supporting areas is pretty much constant whereas the impulse to the pedals is only there during a short period of time.
Therefore it is not the impulse applied to the pedals that is the source of the problem even though it will inevitably contribute to it, it is in essence the pressure area that is the main concern.

Ciao, ;)


fdegrove wrote:
Hi,

Exactly. The sides of the cleats don't exert pressure to the pedal.

Ciao, ;)


Your definitions from the dictionary are terms open to interpretation. Give a physics/engineering statement as that language is not open to interpretation.
You brought up the term "Pressure" earlier. The physical meaning of "Pressure" involves "Surface Area". But you also agreed, and rightly so, "Area" plays no role in stability. So your statements are inherently contradictory.

Correct, Impulse at the pedals/drive only lasts "momentarily" but this is a separete discussion related to power transfer through the system.

Ciao ;)


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Posted: Fri Sep 28, 2012 2:32 pm 


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PostPosted: Fri Sep 28, 2012 3:27 pm 
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Please lock this thread!

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PostPosted: Fri Sep 28, 2012 4:18 pm 
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I agree. totally useless now.

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PostPosted: Fri Sep 28, 2012 5:00 pm 
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A narrow pedal/cleat can be adequate. "can"..."adequate"
A wider platform will make it less prone to rocking. "less prone"
Rocking is not an issue....for some......or a big issue....for some.


One thing is for sure: a gaussian distribution has nothing to do with pressure. :smartass:


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PostPosted: Fri Sep 28, 2012 9:39 pm 
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Hi,

Quote:
Your definitions from the dictionary are terms open to interpretation. Give a physics/engineering statement as that language is not open to interpretation.
You brought up the term "Pressure" earlier. The physical meaning of "Pressure" involves "Surface Area". But you also agreed, and rightly so, "Area" plays no role in stability. So your statements are inherently contradictory.


Making it up as you go, aren't you? :roll:

You're as confused as a barking bird, young man. (That is a non-engineering observation FWIW.)

Mods, pls lock this thread ASAP. Thks.

Ciao, ;)

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PostPosted: Sat Sep 29, 2012 3:25 am 
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horse wrote:
thisisatest wrote:
if the cleat/pedal interface is 10cm wide, and there is 1mm of wear at the sides, it would allow for 0.57degrees of roll.
if the cleat/pedal interface is a mere 1mm wide, and there is 1mm of wear at the sides, it would allow for 45degrees of roll.
the load on the edges of the cleat with respect to foot rolling forces would also be 100 times as great as the 10cm pedal/cleat, greatly increasing the wear rate.


This is utter nonsense. 1mm wide interface and 1mm wear, leaves 0 sum, yet you get 45 deg of Roll/Bank for a disconnected system. I don't see where you get the rest of the derivations without saying anything about the kinematics of the system.


just to chime in on this since it pissses me off so much, i cant resist...
1mm WIDE cleat, 1mm VERTICAL wear. with all the technobabble youve been spewing, im surprised i have to clear that up for you. i never mentioned the HEIGHT of the cleat, therefore it leaves an UNKNOWN sum, but let's pretend it's greater than zero.
what you have left is a 1mm x 1mm gap. versus a 100mm (that's 10cm, it seems like i ought to spell everything out) x 1mm gap on the wider setup.
the issue of wear is chosen for clarity. the 100x force on the edges will be there with or without the wear.
none of this requires derivation, or any calculus for that matter. it's plain, simple geometry. maybe that's the problem? youre trying to incorporate some string theory into this? maybe in some 150th dimension, you make sense.


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PostPosted: Sat Sep 29, 2012 3:38 am 
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BobSantini wrote:
This concern about width is overblown.
There is no good physical reason why a narrow cleat pedal system with a stiff soled shoe can't be adequate.
Good old SPDs have small narrow cleats and they work fine. A little bit of rocking is inconsequential.


for lots of people, it is inconsequential. for some, especially big, tall people with wide feet, and people that need extra stance width, it's a huge deal. one guy i know, 6'3" or so, maybe 190lb, really fast on a bike, used speedplay zeros and would wear out the pedal body on one side in less than a year. the other side took maybe two years. putting him on longer spindles helped, but he would simply put a lot of pressure on the outside of his foot. he would change pedal bodies when his knee would start hurting from what basically amounted to extra varus correction.


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PostPosted: Sat Sep 29, 2012 5:43 pm 
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thisisatest wrote:
just to chime in on this since it pissses me off so much, i cant resist...
1mm WIDE cleat, 1mm VERTICAL wear. with all the technobabble youve been spewing, im surprised i have to clear that up for you. i never mentioned the HEIGHT of the cleat, therefore it leaves an UNKNOWN sum, but let's pretend it's greater than zero.
what you have left is a 1mm x 1mm gap. versus a 100mm (that's 10cm, it seems like i ought to spell everything out) x 1mm gap on the wider setup.
the issue of wear is chosen for clarity. the 100x force on the edges will be there with or without the wear.
none of this requires derivation, or any calculus for that matter. it's plain, simple geometry. maybe that's the problem? youre trying to incorporate some string theory into this? maybe in some 150th dimension, you make sense.


Ridiculous. You ought to spell things out if you bring in new stuff into the discussion. Anyway this is a silly argument you're distracting with. We're NOT talking about any wear in the cleat or pedal!

A) If you wish to calculate Roll you need to know the width of the pedal. You also need to know the torque going into the system (ie, from the rider/shoe to the pedal).
[You're spewing out numbers in your last post without saying anything about this. Foolish.]

B) To calculate Roll (or Stiffness in the Bank axis), the width of the system is a crucial variable.

C) The width of the system is determined by the widest part of the bicycle. That means, at the pedal area, it is the width of the shoe. The shoe is wider than the pedal is most cases. Hence, the width of the cleat brings most closely the width of the shoe to the pedal.

D) Therefore by simply altering/increasing the width of the cleat you are increasing Banking or Rolling Stiffness. Thereby increasing in stability.

In response to "Mr Shop Owner's" claim, let me remind you lot which he says is to simply make the SP pedal "bigger." OK. You then have to make the cleat "bigger" as well. Horse claims this is unnecessary. You make the cleat wider by simply turning it sideways.

Now if you're going to respond with BS or a distraction, don't expect people to take it laying down. It isn't the spirit of the forum. Cyclingnews is some other way.


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PostPosted: Sat Sep 29, 2012 5:45 pm 
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thisisatest wrote:
for lots of people, it is inconsequential. for some, especially big, tall people with wide feet, and people that need extra stance width, it's a huge deal. one guy i know, 6'3" or so, maybe 190lb, really fast on a bike, used speedplay zeros and would wear out the pedal body on one side in less than a year. the other side took maybe two years. putting him on longer spindles helped, but he would simply put a lot of pressure on the outside of his foot. he would change pedal bodies when his knee would start hurting from what basically amounted to extra varus correction.


That, or increase Q-Factor.


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PostPosted: Sat Sep 29, 2012 5:54 pm 
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BobSantini wrote:
This concern about width is overblown.
There is no good physical reason why a narrow cleat pedal system with a stiff soled shoe can't be adequate.
Good old SPDs have small narrow cleats and they work fine. A little bit of rocking is inconsequential.


Explain it to them why a narrow system with a stiff sole is adequate.
A wide cleat mated to the shoe essentially translates the width of the shoe to the pedal, irrespective of the width of the pedal, even narrow SPD pedals.


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PostPosted: Sat Sep 29, 2012 6:01 pm 
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Rick wrote:
One thing is for sure: a gaussian distribution has nothing to do with pressure. :smartass:


I'm not the one involving "Pressure." I already spent two posts explaining why.


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PostPosted: Sun Sep 30, 2012 10:05 pm 
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:popcorn:

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PostPosted: Mon Oct 01, 2012 4:20 am 
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For what it's worth (and as the only one here with a set of these, I'd wager it's worth a bit more than the bickering above), I have not had any hotspot problems. Stability is similar to the Look Keo Blades I'm coming off of. Much more stable than an SPD, certainly.

I have a preproduction set and the cleat does not offer as much adjustment as I would like, both angular and fore/aft. I've informed them of this and hopefully they can make a running change. It's a pretty simple fix (in fact, I fixed it myself with a file...).

The clip in/out motions are becoming much more intuitive. Clipping in still takes longer, as I rarely find the pedal with that small slot on the first try. Clipping out is easy, requiring very little effort once you get the muscle memory and aren't trying to kick your foot through the crank anymore. I haven't toppled over yet.

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PostPosted: Mon Oct 01, 2012 4:31 am 
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VNTech wrote:
For what it's worth (and as the only one here with a set of these, I'd wager it's worth a bit more than the bickering above), I have not had any hotspot problems. Stability is similar to the Look Keo Blades I'm coming off of. Much more stable than an SPD, certainly.

I have a preproduction set and the cleat does not offer as much adjustment as I would like, both angular and fore/aft. I've informed them of this and hopefully they can make a running change. It's a pretty simple fix (in fact, I fixed it myself with a file...).

The clip in/out motions are becoming much more intuitive. Clipping in still takes longer, as I rarely find the pedal with that small slot on the first try. Clipping out is easy, requiring very little effort once you get the muscle memory and aren't trying to kick your foot through the crank anymore. I haven't toppled over yet.

Thanks for the post :D :thumbup:

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Posted: Mon Oct 01, 2012 4:31 am 


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