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flag Naaronson
Posted: Oct 27, 2009 at 16:50 Quote
bigquotesmuch better explanation than mine! thanks! one quick question though, i was under the impression that even denominators doubled and odd denominators remained the same for ambidextrous skidders?

I'm pretty sure Sheldon Brown is right, because if you're ambidextrous, you skid on completely the opposite part (or 180 degrees round) of the wheel when you skid with your opposite foot. If the denominator was even, the opposite part of the wheel would already be one of your skid patches, so by doubling the number you would be counting each skid patch twice, therefore your result would be wrong. The opposite is true for an odd denominator, that skidding with you're other foot skids in exactly the opposite part of the wheel, but due to the denominator being odd, none of the skid patched are opposite each other and therefore you must double the denominator to count all the extra skid patches.

Whew. That was hard to explain and it probably makes no sense at all, but I tried.
flag bigal243
Posted: Oct 27, 2009 at 16:59 Quote
Naaronson wrote:
bigquotesmuch better explanation than mine! thanks! one quick question though, i was under the impression that even denominators doubled and odd denominators remained the same for ambidextrous skidders?

I'm pretty sure Sheldon Brown is right, because if you're ambidextrous, you skid on completely the opposite part (or 180 degrees round) of the wheel when you skid with your opposite foot. If the denominator was even, the opposite part of the wheel would already be one of your skid patches, so by doubling the number you would be counting each skid patch twice, therefore your result would be wrong. The opposite is true for an odd denominator, that skidding with you're other foot skids in exactly the opposite part of the wheel, but due to the denominator being odd, none of the skid patched are opposite each other and therefore you must double the denominator to count all the extra skid patches.

Whew. That was hard to explain and it probably makes no sense at all, but I tried.
no it does make sense. but the rabbit skid patch calculator gives 15 skid patches for a 44:15, for both ambidextrous and not?
flag Naaronson
Posted: Oct 27, 2009 at 17:46 Quote
photo

4210401


What I was trying to say before is:

On the left wheel there is an even number of skid patches, 4.
On the right wheel there is an odd number of skid patches, 3.
On the left wheel, the left foot forward (LFF) skid patches are in exactly the same places as the right foot forward (RFF) skid patches, thus you do not double the number of skid patches for ambidextrous skidders.
On the right wheel, the left foot forward (LFF) skid patches are in the opposite places as the right foot forward (RFF) skid patches, thus you do must double the number of skid patches for ambidextrous skidders.

So for a 44:15 setup, there are 15 skid patches for the LFF and 15 different skid patches for the RFF, positioned at 180 degrees further around the wheel than on the LFF. Thus in total there are 30 skid patches if you ambidextrously skid.

I might be totally talking out of my ass here as I don't even own or ride a fixie, but I love maths and mechanics, so I tried working it all out on my head and I think that this is correct.
flag Naaronson
Posted: Oct 27, 2009 at 17:47 Quote
Oh shit I just noticed you said
bigquotesno it does make sense
Where I thought I read no it doesn't make sense...

Ah well ignore all of the previous post, I am far too tired I should probably hit the hay...
flag bigal243
Posted: Oct 27, 2009 at 17:50 Quote
Naaronson wrote:
photo

4210401


What I was trying to say before is:

On the left wheel there is an even number of skid patches, 4.
On the right wheel there is an odd number of skid patches, 3.
On the left wheel, the left foot forward (LFF) skid patches are in exactly the same places as the right foot forward (RFF) skid patches, thus you do not double the number of skid patches for ambidextrous skidders.
On the right wheel, the left foot forward (LFF) skid patches are in the opposite places as the right foot forward (RFF) skid patches, thus you do must double the number of skid patches for ambidextrous skidders.

So for a 44:15 setup, there are 15 skid patches for the LFF and 15 different skid patches for the RFF, positioned at 180 degrees further around the wheel than on the LFF. Thus in total there are 30 skid patches if you ambidextrously skid.

I might be totally talking out of my ass here as I don't even own or ride a fixie, but I love maths and mechanics, so I tried working it all out on my head and I think that this is correct.
this more or less makes sense. but im 99% sure you still only get 15 skid patches if your ambidextrous and run a 44:15. your figures and everything do make sense, but im not sure if its necessarily right. i think someone who isnt me or you needs to answer this
flag Naaronson
Posted: Oct 27, 2009 at 17:52 Quote
I agree Razz It's very confusing.
flag AxionJaxon
Posted: Oct 27, 2009 at 19:02 Quote
Naaronson wrote:
I agree Razz It's very confusing.

Yeah haha, just use the skid patch analysis tool I posted on the last page and remember that the more skid spots the better!
flag singlespeedtoday
Posted: Oct 27, 2009 at 22:03 Quote
It makes sense. 44:15 gets 15 skid patches either way.
flag bigal243
Posted: Oct 27, 2009 at 22:06 Quote
singlespeedtoday wrote:
It makes sense. 44:15 gets 15 skid patches either way.
obviously, but why? is it because you cant simplify 44:15 or what?
flag singlespeedtoday
Posted: Oct 27, 2009 at 22:26 Quote
Now i'm not sure. I confused myself.
flag Hombre3000
O+
Posted: Oct 27, 2009 at 23:28 Quote
Simplify as much as possible. The resulting denominator is the number of skid patches.
flag bigal243
Posted: Oct 27, 2009 at 23:33 Quote
Hombre3000 wrote:
Simplify as much as possible. The resulting denominator is the number of skid patches.
we know that. we are now trying to figure out why ambidextrous skidding doesnt always double your skid patches. for instance with a 42:16 you get 16 skid patches versus 8 if you are an ambidextrous skidder. however with a 44:15 you end up with 15 skid patches regardless of whether or not you skid ambidextrously. why?
flag Naaronson
Posted: Oct 28, 2009 at 6:19 Quote
So basically Sheldon Brown says to double the denominator if it is odd (for ambidextrous skidding) but rabbit applet doubles it when it is even...?
flag ammosally
Posted: Oct 28, 2009 at 7:21 Quote
My head nearly exploded over all that...
Rained lastnight here, going to take the fixie out and learn how to skid in the grass and piss off the landlord... Wink
flag Hombre3000
O+
Posted: Oct 28, 2009 at 7:22 Quote
Shoot. I'd have to figure this out with angles.

 


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