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  #1  
Old 02-09-2019, 01:09 PM
zmalwo zmalwo is offline
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Just realized the irony of disc brakes on an aero bike.

I rarely have these genius moments but this is for sure one of them. The whole purpose of an aero bike is to use them on flat stages where constant speed is high enough that the aero advantage of aero tubes offsets the weight penalty, and the purpose of disc brakes are to avoid overheating of carbon brake tracks on mountain stages where lots of braking take take place. If an aero bike is not used on mountain stage, then caliper brakes would offer better aero gain than disc brake, as well as reducing overall weight close to 6.8kg as aero bikes rarely make to that light. But since everything in the bike industry is about marketing and forced gear retirement, the manufactures probably don't want you to know this. One can argue that discs offer better braking in wet weather, but with recent year pads and brake track improvement I highly doubt discs even offer that much better braking performance.
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Old 02-09-2019, 01:13 PM
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zzy zzy is offline
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Your underlying assumptions are incorrect. Even aero bikes have no problem hitting the UCI minimum. Well engineered aero frames with flatmount disc brakes have better aerodynamics than caliper brakes, depending on who you believe.
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Old 02-09-2019, 01:14 PM
KonaSS KonaSS is offline
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And better braking is better braking, applies to flat roads, wet weather, and downhills.
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  #4  
Old 02-09-2019, 01:37 PM
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Mike V Mike V is online now
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"Better"
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  #5  
Old 02-09-2019, 01:51 PM
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  #6  
Old 02-09-2019, 02:06 PM
Burnette Burnette is offline
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Ha!

Quote:
Originally Posted by zmalwo View Post
I rarely have these genius moments but this is for sure one of them. The whole purpose of an aero bike is to use them on flat stages where constant speed is high enough that the aero advantage of aero tubes offsets the weight penalty, and the purpose of disc brakes are to avoid overheating of carbon brake tracks on mountain stages where lots of braking take take place. If an aero bike is not used on mountain stage, then caliper brakes would offer better aero gain than disc brake, as well as reducing overall weight close to 6.8kg as aero bikes rarely make to that light. But since everything in the bike industry is about marketing and forced gear retirement, the manufactures probably don't want you to know this. One can argue that discs offer better braking in wet weather, but with recent year pads and brake track improvement I highly doubt discs even offer that much better braking performance.
You, by yourself, have discovered what nobody in the whole world could. That you can sit on the couch and make stuff up to the point that you believe it true.
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  #7  
Old 02-09-2019, 02:49 PM
54ny77 54ny77 is offline
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just take a giant bong rip, turn on a hairdryer, and exhale while kneeling in front of bike with hair dryer pointing to rear of bike to see the aerodynamic drag.

then calculate the coefficient of friction as the square root of the thc content multiplied by the v02 max of the rider divided by the gear inches of the top gear configuration.
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  #8  
Old 02-09-2019, 02:51 PM
Jaybee Jaybee is offline
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Quote:
Originally Posted by 54ny77 View Post
just take a giant bong rip, turn on a hairdryer, and exhale while kneeling in front of bike with hair dryer pointing to rear of bike to see the aerodynamic drag.

then calculate the coefficient of friction is the square root of the thc content multiplied by the v02 max of the rider divided by the gear inches of the top gear configuration.
It's early, but this is a solid POTY candidate
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  #9  
Old 02-09-2019, 02:53 PM
XXtwindad XXtwindad is offline
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Quote:
Originally Posted by 54ny77 View Post
just take a giant bong rip, turn on a hairdryer, and exhale while kneeling in front of bike with hair dryer pointing to rear of bike to see the aerodynamic drag.

then calculate the coefficient of friction as the square root of the thc content multiplied by the v02 max of the rider divided by the gear inches of the top gear configuration.
Damn this is funny.
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  #10  
Old 02-09-2019, 02:53 PM
Spdntrxi Spdntrxi is offline
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you have a low bar for genius moments
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  #11  
Old 02-09-2019, 03:07 PM
Joxster Joxster is offline
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There was a minor faux pas from Mavic support during the tour last year. Dan Martin recieved a double wheel change at the start of a descent, he's running discs. after 10km of descending the team car comes up and does a bike change. Mainly because things were a bit iffy on the descent and he was running 160 rotors but Mavic gave him 140's
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  #12  
Old 02-09-2019, 03:12 PM
Burnette Burnette is offline
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I'm In

Quote:
Originally Posted by zzy View Post
Your underlying assumptions are incorrect. Even aero bikes have no problem hitting the UCI minimum. Well engineered aero frames with flatmount disc brakes have better aerodynamics than caliper brakes, depending on who you believe.
Quote:
Originally Posted by 54ny77 View Post
just take a giant bong rip, turn on a hairdryer, and exhale while kneeling in front of bike with hair dryer pointing to rear of bike to see the aerodynamic drag.

then calculate the coefficient of friction as the square root of the thc content multiplied by the v02 max of the rider divided by the gear inches of the top gear configuration.
Finally, we're doing livingroom research again! I'll bring the Mountain Dew, Doritos and Oreos. Does anybody here have enough hair left that they actually have a hair dryer? If so, bring it.
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  #13  
Old 02-09-2019, 03:16 PM
54ny77 54ny77 is offline
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landis should lead the research effort.

maybe even come up with cbd chain oil.

Quote:
Originally Posted by Burnette View Post
Finally, we're doing livingroom research again! I'll bring the Mountain Dew, Doritos and Oreos. Does anybody here have enough hair left that they actually have a hair dryer? If so, bring it.
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  #14  
Old 02-10-2019, 06:46 AM
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oldpotatoe oldpotatoe is offline
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Quote:
Originally Posted by Joxster View Post
There was a minor faux pas from Mavic support during the tour last year. Dan Martin recieved a double wheel change at the start of a descent, he's running discs. after 10km of descending the team car comes up and does a bike change. Mainly because things were a bit iffy on the descent and he was running 160 rotors but Mavic gave him 140's
Hmmmm...I thought the UCI agreed on some sort of ‘standard’ that it would be 12mm TA front and back and 140mm rotors??

BTW, I worked on a tri bike for Drew Scott that had these really awful, integrated into the fork legs and underneath chain stays, blade type brakes that were, VERY aero. Had to be more aero than any caliper/rotor setup...only problem, they didn’t farming work!!!
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Last edited by oldpotatoe; 02-10-2019 at 06:50 AM.
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  #15  
Old 02-10-2019, 07:08 AM
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R3awak3n R3awak3n is offline
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Quote:
Originally Posted by Burnette View Post
You, by yourself, have discovered what nobody in the whole world could. That you can sit on the couch and make stuff up to the point that you believe it true.
lol


I do like that this is not turning out to a disc sucks thread. Well done everyone
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