Movistar rider injured by disc brake in Paris-Roubaix

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BikeAnon
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by BikeAnon

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spookyload
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by spookyload

Gavf wrote:
spookyload wrote:
WTF kind of bars are you running that you can cut them and save 56g? Most WW bars are under 200g, so by your distorted math, you cut a 1/4 of your bars off? BTW, the majority of the weight in bars is in the top reinforced area, so I am guessing you just went ahead and cut a third of your bars off. Seems legit.


Carbon bars, each drop was cut off, each one weighed 28grams.

You might want to google it, as it is very common.

I am very sorry actual facts disagree with you, again.

spookyload wrote:And please tell me what does that have to do with your seatpost and saddle weight? Again, as you keep mentioning, I am obviously inept at math and physics, which involve numbers, so please show me your genius and give me actual numbers that translate grams in to watts saved going up a climb. Numbers, not simply you saying how smart you are and how dumb I am.

Again, this is very easy for any layman to work out.

If two riders each produce 400watts for ten minutes and each weigh 70kg, who will get to the top of the climb first

1, - bike weighing 7kg

or

2, - bike weighing 6.5kg

If you disagree with the well accepted basic science, like gravity, then don't respond at all.


Fantastic. Numbers. Not that they mean jack however. In your mathematical theory, you should simply be able to look at the weight of someones bike and his weight and figure out who will win. It is all about simple weights. How has Froome ever won a TdF with his super overweight Pinarello, when other teams are riding such lighter bikes? Again, I asked you to show me real math. How much does an extra 60g cost a rider in power over a 12 km climb with varying gradients? Your math is irrelevant because you want to assume every rider can produce the same power and weighs the same. That isn't the case ever, so what you said is worthless. Anyone who has finished high school understands F=MA, but that isn't what you were spouting earlier. Judging from your vague responses of "everyone knows", I am guessing you don't actually know, but assume stuff you have read means that. Your thread responses always seem to lead to you attacking people, calling them stupid for being American and trying to understand bikes, and finally just leaving.

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Gavf
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by Gavf

spookyload wrote:Fantastic. Numbers. Not that they mean jack however. In your mathematical theory


Agree or disagree with the following statment i made previous, until i get your answer the debate can not go on.

If two riders each produce 400watts for ten minutes and each weigh 70kg, who will get to the top of the climb first

1, - bike weighing 7kg

or

2, - bike weighing 6.5kg


stupendous was an autocorrect for stupid, i have never even heard of the word before now. :D

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euan
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by euan

The psychology effect of using lightweight parts in hillclimbs is hilarious. I would have won if my bike was lighter etc. The reality is hillclimbs are won by margins of seconds, the ones the matter anyway. That would require hundreds and hundreds of grams to be removed in the case of a climb like Jackson Bridge used in the last British Hillclimb champs.

wingguy
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by wingguy

Gavf wrote:
wingguy wrote:Given that Henao is top 20 in GC, and was Skys top GC rider remaining in the race when those weights were takn what on earth makes you think he is riding a bike considerably heavier than Landa's would have been? Why would they do that? Do you think Sky is in the habit of intentionally sabotaging their main hope on any given day?


Why don't you go and ask Sky


That would be pointless. They'd look at me and say 'WTF are you talking about? Henao's bike is the same as Landa's'

wingguy wrote:Math it out for me.


I am not going to waste my time explaining power to weight ratios, when it is a very common and easy calculation any 12 year old could do.


You don't need to explain power to weight ratios, you need to math out how much time that 56g of bar is going to save you if you want to salvage any credibility. No one is denying that power to weight is a thing, they're saying that you are hugely overestimating the effect.

There are many hill climb events that have decents and brakes are absolutly needed, no one ever would use discs though, that would be utterly stupendous.


ANd you ride those faster when you can't sit down, do you? Remarkable!

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ergott
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by ergott

wingguy wrote:you need to math out how much time that 56g of bar is going to save you if you want to salvage any credibility.


Here.

Rider - 165lbs
Bike #1 - 16lbs
Bike #2 15.88lbs (about 56g lighter)
Power output - 300 watts
course - Mt. Washington

result?
3 seconds

https://www.bikeshopbelair.com/mt-washi ... climb.html

:beerchug:

I would argue that 3 seconds is smaller than the margin of error for any calculator due to environmental factors. Also, if you were receiving time checks you could conceivably dig a bit deeper for those 3 seconds. That's the human psyche.

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HammerTime2
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by HammerTime2

ergott wrote:I would argue that 3 seconds is smaller than the margin of error for any calculator due to environmental factors.
Your argument may be correct, but the implied conclusion from your argument incorrect. The time error due to uncertainty in environmental factors is likely common to 1st order between the heavier and 56 g lighter bikes. Therefore, to 1st order, the contribution of the uncertainty in the environmental factors cancels out when the times for the 2 bikes are subtracted. I.e., common error is canceled when data is differenced. :beerchug:

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ergott
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by ergott

3 seconds over 4100 seconds.

Two riders won't experience the same exact environmental conditions even if they race on the same day. 3 seconds could be a good gust of wind above the tree line. You will never be able to isolate weight and have identical conditions for all else. Therefore you can't conclude that the rider with 56g lighter bike will definitely win given the same power and weight. 3 seconds isn't enough to overcome other environmental conditions.

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Calnago
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by Calnago

The will to win can't be measured on a scale or a wind tunnel.
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BikeAnon
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by BikeAnon

ergott wrote:.....Two riders won't experience the same exact .....

I'd argue we are not taking about two riders. Were talking about one rider, with two different setups.

If one rider chooses his lighter setup, he will get up that hill faster than he would have with the heavier set up.

If he wins the race by two seconds, his shaved 56 grams could have been the deciding factor.

A pro in the video I posted has his "every day"/"sprinter" and his hill-climbing setup. The two bikes are only 100 grams different.

Why is that impossible to believe? Especially here, where we pay $$$ to shave a gram.


Back on topic... the idea of brake weight should be a nonissue. Di2 is unquestionable heavier than mech. Did that stop the pros from adopting. Hell no. Because the performance increase made it worth it.


AND, there's the pesky UCI minimum that makes all of the discussion about weight meaningless, as any builder can now bring bikes in at or below UCI rules.

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ergott
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by ergott

BikeAnon wrote:
If he wins the race by two seconds, his shaved 56 grams could have been the deciding factor.
.


Yes. So let's put that 3 second advantage for the Mt Washington Hill climb into a comparative number for a less extreme climbing example. That 3 seconds is a 0.07% reduction in time.

I'd rather have the ends of my handlebars.

Point I'm making is sometimes the decision to reduce weight shouldn't make the bike less advantageous to ride when most of our riding is on mixed terrain, not hill climbs with no descents.

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kgt
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by kgt

Many members in this forum use numbers, data, models and 'science' in order to set their arguments.
Their problem is that they have not a clue how all these are related to the real world...

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spookyload
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by spookyload

Calnago wrote:The will to win can't be measured on a scale or a wind tunnel.


100% correct. :beerchug:

fogman
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by fogman

It appears as though the reinstatement of disc brake testing in the pro peloton may be delayed.
http://www.bicycleretailer.com/internat ... 1DQNvT3bCR


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It's all downhill from here, except for the uphills.

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tabmaster
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by tabmaster

That is such a shame...
If the grand tours are like classical music, kermesse racing is punkrock, Belgian style.
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