Peezy's Black Magic 2013

Yes, but i cant change my spot as per DH. They are doing the chip timing now and cant swap that kind of stuff.
 
what's the gearing on it now?

and is this the Madness of Madness that doesn't post here anymore Madness?
 
I think Jay has it 34x20. I have a hard time counting cogs because I can't keep track of where I started 😛

Yes, THEE Belt Buckle Madness himself! Seen him twice in the past two weeks.
 
pearl said:
I think Jay has it 34x20. I have a hard time counting cogs because I can't keep track of where I started 😛

Yes, THEE Belt Buckle Madness himself! Seen him twice in the past two weeks.
Click to expand...

34x20... i have no idea how that translates. as soon as you change the 32 upfront to something else, i can't figure out what's easier/harder. i guess 34x19 would be somewhere like 32x18, which is kinda like 32x16 on a 26er, which is what i can relate to, so 34x20 on a 29 is like 32x18 on a 26, but not quite?

the madness! son of a B. every once in a while i'll see him on his bike around town. we must live a few yards from each other. i rode with him about 8 million years ago at 6 mile. he was pretty fast.
 
I have to use Sheldon Browns gear calc to figure it out, I used to have it printed out so I could reference it quick, but I gave up the SS lyff

I can't remember what I ran last year, which is what is killing me
 
pearl said:
Yes, but i cant change my spot as per DH. They are doing the chip timing now and cant swap that kind of stuff.
Click to expand...

Mandell bailed on the SSAP to do FairHills. That may be an option if you feel like reaching out to him.
 
clarkenstein said:
34x20... i have no idea how that translates. as soon as you change the 32 upfront to something else, i can't figure out what's easier/harder. i guess 34x19 would be somewhere like 32x18, which is kinda like 32x16 on a 26er, which is what i can relate to, so 34x20 on a 29 is like 32x18 on a 26, but not quite?
Click to expand...

34:20 is slightly less than 32:18 (~ two gear inches -- "direct drive" equivalent of 49.3 vs. 51.6) A 32:16 on a 26er is a pure 52, so it's more or less the same as a 32:18 on a 29er (unless anybody thinks they can detect a difference of .4 gear inches.)

I've never been a fan of the whole direct drive equivalency thing, though. It's not exact measurements, for one thing and second, the output metric doesn't realy tell you the thing you care about -- distance you travel for one pedal stroke on one vs. the other. It's off by a factor of pi on that. I know that all cancels out in a comparison, but I used to hate it when my wife's friends on the track would talk about their gears and describe them as an "88" or a "92" or something like that because that value is only good when comparing one vs. another. Talking about a single gear, you should translate to distance. Like if I say I'm running a 32:18 on a 29er, what I care about in that is that for the work I do I'm getting a certain distance out of it. And that distance is missing a factor in the gear inches metric. The distance I travel is the outer circumference of the wheel (which may actually make my 29er more like a 33er assuming a conservative 2 inches of height above the rim for the inflated tire) multiplied by the gear ratio. So if I have a true 2:1, the simple fact is that for every full turn of the crank, my rear wheel travels a distance equal to twice its circumference, which would be something on the order of 66 inches in my example. Of course there are other factors that I don't consider here (compression on the wheel, and nusiance factors like crank length, etc.) but I think it's a more meaningful number than calling a 32:18 a "51.5" as the standard goes.
 
Last night was fun as all heck. You looked way too comfortable on that SS. 6mile felt like CR on the cross bike. The first half of ride was sketchy but after I got comfortable it was pure awesomeness :getsome: Will be back soon for sure!
 
Doing the Math

James -

all of those symbols are things you already know! it is just the way the engineers quantify it. this got longer than i wanted...concept might be enough to explain why higher cadence may help.

the concept...

you asked about watts - which is power at a given time - just like looking at a thermometer is the measure of temp at a given time. the 345w is the average necessary to maintain that speed.

this is important, because producing power over an amount of time is energy (like your electric bill - 60w bulb, on for 5 hours consumes as much as 100w on for 3)

why is this important - well using the light bulb, consider your headlamp - on high it consumes the battery much faster than low - but the difference in the amount of light isn't much - to go just a bit faster requires much more power over nearly the same amount of time...hence consuming more energy.

You are the battery - if not fully drained, there must be a way to produce more watts (ie, as suggested - dropping a gear and spinning faster higher average watts, more energy consumed) - this works up to the maximum throughput or breaking point of the system or an empty tank.

there may even be a combo that uses more energy - like downshifting mid-segment....standing means less aero, but the ability to produce more power.....

-----kinda boring below here, but to understand the equation---

now to the math -

the first part is the energy required to move the bike, the person, and the resistance of the bike - with respect to speed and grade.

the resistance of the bike (K1) - it is like hanging your bike in the trainer and not engaging the resistance wheel - very easy, but does require pedaling to keep it going. again an average number, since not all bikes are created equal

then the weight (mass) of the bike and person. Utah's example simplified it to flat ground, but consider you vs Jake going up zion at 10mph - jake will require a higher power level to climb at 10mph. the really interesting part here, is how fast this goes negative on a downhill grade, and having a higher mass becomes an advantage - see you knew this.

the second part of the equation is wind resistance - the K2 is the average wind resistance of person and bike - well we know this is different for each person/bike - hence skin suits, tt bikes, aero stuff, frontal area of rider in some position - you knew this...

the formula has a wind factor - this adjusts the outcome for headwind/tailwind component - tail wind makes it easier (it would be a negative number) headwind harder. You already knew this!

now the tricky part - that Va^2 factor -
you ride your bike with ease at 15mph, but it is all you can do to go 30mph - well the wind resistance at 30mph is 4 times that at 15, it doesn't matter if you are on a light or heavy bike, what you weigh, or how aero you are....damn sure you knew that overcoming the wind resistance was a major factor...

in numbers, the difference between maintaining 26.3mph and 27mph is 27watts - the difference between 25.6 and 26.3 is 22watts - same small increment (.7mph) , but the first one required 25% more power....

-----now, to the real question ----

how do i take my street back???

ride without a helmet :popcorn:
 
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Want to ride together? Then after the race we can spoon.

I'm going to try and bring a cake. But you need to eat it with a ladle.
 
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