New pedals and cranks

So I replaced the cranks and pedals on my 24" Schwinn, since one of the cranks got stripped. I got the same 140 mm Schwinn cranks, but got different pedals. I got the Odyssey Twisted Pro Pedals. They’re heavier than the Schwinn pedals but seem much better. They’re also larger which seems to provide much more solid balance. The switch to metal pedals makes riding seem a lot different. The pins certainly make me stick to the pedals, but sometimes I can’t adjust my foot very well if I get it on the edge of the pedal. Also I already got smacked in the back of the leg and it wasn’t fun, so I think I’ll remove the pins. Another thing is that the Q factor seems really big. Is this a bad thing? The cranks seem secure, but should I hammer them further on? What does everyone else think about these pedals? Do most people use metal pedals? with pins?

As long as the new cranks are the same as the old cranks the Q-factor didn’t change. Q-factor is a property of the cranks and the width of the hub. The pedals are not factored into that measurement. However, with some pedals your feet will center themselves further away from the crank so pedals can affect your Q-factor. For more on Q-factor see
<http://www.sheldonbrown.com/cranks.html#tread>

I use metal pedals on my outdoor unicycles. This includes my Coker, trials uni, and munis. I use plastic pedals on my freestyle unicycle. You’d have to be crazy to put metal pedals on a freestyle unicycle - you would hurt yourself too often and you wouldn’t be able to ride the unicycle indoors.

When I first switched to metal pedals for muni I started with a pedal that didn’t have replaceable pins. The pedal just had blunt knobs. It was grippy enough for riding in dry weather and let me get used to metal pedals. I then switched to a more aggressive metal pedal with pins. You’ll get used to moving your feet on the pedals eventually. You have to lift your foot up off the pedal to move your foot on the pedal. It takes practice and you can’t really do it on rough ground.

Unless you’re doing muni or riding in wet weather you can get by with a less aggressive metal pedal, something that uses nubs instead of pins. You’ll get the durability of a metal pedal without the severe consequences if the pedal hits your calf or shin. If you want to still be able to ride indoors or on other surfaces that can be damaged by metal pedals (like some tennis courts) then the plastic Twisted PC pedals are good
<http://www.unicycle.com/shopping/shopexd.asp?id=213>
and they offer good grip except for in the rain.

Good reply John!

I also have metal pedals on all my outdoor unis… hey wait that’s ALL my uni’s as we don’t have an indoor space to ride in so no worries about having indoor pedals… ah, but I digress.

I also started with the metal pedals with nubs but as I got better at adjusting my foot on the pedal and as I came to appreciate more and more the advantages of having a firm connection between foot and pedal especially when riding in the rain or doing MUni, I went to pinned pedals on all my uni’s. Of course the MUni has the most aggressive pin pedals and I love that feel of being downright ‘stuck’ to them. But even my 24 inch commuter uni had some pretty sticky pin pedals and are they awesome when riding on those slippy rainy west coast days.

Erin

Keep trying with the pinned pedals. The extra control and torque they will give you once you get used to them is worth it.

Q factor is (put simply) how far apart your feet are (widthways) - so if your feet are wide apart, you are pushing the pedal when it is quite a long way to one side of the centre of the tyre tread. This can make the uni weave and wobble a bit. I doubt that the difference between two sets of cranks is enough to make a real and permanent difference. You will adjust your style without realising it.

John, you seem to contradict yourself here. Is the Q factor based on
the distance from outer crank face to outer crank face, or on centre
pedal to centre pedal, or possibly yet something else?

Also, can Q factor be quantified? Then, is it a distance measure, or
is crank length factored in in some way as well? Either way, it
doesn’t seem to be a FACTOR, does it?

Klaas Bil - Newsgroup Addict

i got my ‘ered’ and ‘less’ just mixed up - Sofa

[REPOSTED ON THE FORUM; ONCE MORE THE LINK IS DOWN]

According to the Sheldon Brown article John gave the link to,

The tread, or “Q factor” of a crank set is the horizontal width of the cranks, measured from where the pedals screw in.

So it is a length, quantified, independent of the pedals.

That said, if you have a wider set of pedals, and your feet are centered on the pedals, your feet will be further apart. So perhaps the definition of Q-factor is missing a piece. This is not a big deal if you are using clipless pedals, which is the norm for bicyclists that are worried about Q. That said, probably most unicyclists, on average, place each foot as close to the inner edge of the pedal as allowed by the crank, which changes the complicating aspect to foot width, not pedal width.

It is a factor when you look at the definition of torque, which is force times moment-arm.

Re: New pedals and cranks

On Thu, 20 Feb 2003 20:20:07 -0600, john_childs
<john_childs.j6ica@timelimit.unicyclist.com> wrote:

>As long as the new cranks are the same as the old cranks the Q-factor
>didn’t change. Q-factor is a property of the cranks and the width of
>the hub. The pedals are not factored into that measurement. However,
>with some pedals your feet will center themselves further away from the
>crank so pedals can affect your Q-factor.

John, you seem to contradict yourself here. Is the Q factor based on
the distance from outer crank face to outer crank face, or on centre
pedal to centre pedal, or possibly yet something else?

Also, can Q factor be quantified? Then, is it a distance measure, or
is crank length factored in in some way as well? Either way, it
doesn’t seem to be a FACTOR, does it?

Klaas Bil - Newsgroup Addict

i got my ‘ered’ and ‘less’ just mixed up - Sofa

I know, I was aware of that contradiction as I wrote it, but was too lazy to provide an explanation. I should have put in a Klaas disclaimer :slight_smile: for the logical discontinuity.

Going by the strict definition of Q-factor it is the horizontal width of the cranks when mounted on the bike/unicycle. There is nothing to do with pedals in that measurement. However, in actual use people think of Q-factor as how far apart their feet are and going by that common definition of Q-factor the pedals do have an effect on Q-factor.

I don’t notice that my different pedals affect the Q-factor (going by the common definition of Q-factor here) much. Most pedals are consistent in where you foot naturally wants to be and don’t cause a noticeable effect on the Q-factor. However, if you put some pedal spacers on like these <http://www.unicycle.com/shopping/shopexd.asp?id=670&gt; then that would very likely affect how wide apart your feet are and your perceived Q-factor.

I think I saw somewhere that the Schwinn hub is the widest one available. So when I put on these new pedals that were so much bigger than the original Schwinn pedals I really noticed the large Q factor. Any ideas as to what small or large Q factors allow/disallow you to do?

Re: New pedals and cranks

On Sat, 22 Feb 2003 09:46:29 -0600, U-Turn
<U-Turn.j9hzh@timelimit.unicyclist.com> wrote:

>It is a factor when you look at the definition of torque, which is force
>times moment-arm.

Thanks for the explanation (which I snipped). I’m not sure about why
it is a factor though. The moment-arm is, precisely due to the Q
factor being non-zero, not in a plane perpendicular to the axle.
However, the useful definition of torque (“useful” torque) would only
include the component of the moment-arm in that perpendicular plane.
For that useful torque, Q-factor is hence irrelevant.

So, I still wonder why is is called Q-factor. It would make more sense
if it were Q-distance.

Klaas Bil - Newsgroup Addict

The world is full of apathy but I don’t care.

Re: Re: New pedals and cranks

Just a guess, but could it be called Q-Factor because it sounds more hip ‘n’ happenin’ than Q-Distance, rather than any technical reason?

John,

Please refrain from conforming your thinking to what some imagined group of bubble-heads think- we like the way you think just fine, thank you.

My muddled use of Q referes to how un-straight the crank is; I only like significant amounts of Q if the cranks are short and the type of riding is such that my heal will catch on the rising crank if it is straight (such as on a small -12 or 16"- wheel).

I’m finally getting used to the ultra-grippy B-27’s; I was able to torque up a muddy slope today that would have been hopeless with less grippy pedals. Unintended dismounts are still a bit frightening- so far my foot has come off the pedal before my face hits the ground- but just bairly.

-Christopher

Re: Re: New pedals and cranks

Because that is what the folks who created the Fit Kit decided to call it. The Fit Kit is a contraption that bike shops can use to help you get a correct fit on a bike. They’re the ones that came up with the Q-factor name. Blame them. I assume it was engineers who designed the Fit Kit and they should have known better.

Well (says a bubble-head) the very fact that it describes the distance of the crank face from the wheel plane (x2) implies the torque that it is talking about - the torque that tends to move your wheel from a straight line (yaw). Although for high-speed riding, wheel-wobble can be a thing to eliminate, it’s exactly yaw that lets us steer and keep our side-to-side balance. In that sense, then, this torque, perpendicular to the driving torque, is also “useful”.

Since that distance goes into the equation as a factor, the appellation “factor” is accurate and helpful.

The guys who design frames have to take this torque into account when modelling frames and frame flex of various kinds. So they are/were probably truly thinking of the torque equation when they named it. But this “also-useful” torque is more useful to us than those poor two-wheeled cyclists.

Re: Re: New pedals and cranks

But this is English! Not some sensible language. Trying to make sense of the English language surely can be a time-consuming hobby, but must eventually end in insanity.

How about using “Tread,” as Sheldon Brown calls it? Is that one better or worse?

“Tread” is worse because it includes/implies a rider-specific aspect, the distance between rider’s foot centers. “Q-factor” is only cycle-dependent.

Re: New pedals and cranks

On Tue, 25 Feb 2003 13:52:18 -0600, U-Turn
<U-Turn.jf9mb@timelimit.unicyclist.com> wrote:

>> Is that one better or worse?
> “Tread” is worse because it includes/implies a rider-specific aspect,
>the distance between rider’s foot centers. “Q-factor” is only
>cycle-dependent.
I was exactly gonna say that. And also, John, if* it is a distance
rather than a factor, this has little to do with English. It’s unclean
thinking, the result of which is just expressed in English, that’s
all.

  • (I’m saying ‘if’ because U-Turn had a good point about why said
    distance is a factor too.)

Klaas Bil - Newsgroup Addict

A whale’s penis is called a dork.