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Paris-Roubaix inovations


Nish4

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I suspect these cantilever brakes were a pre-emptive measure for mud clearance or' date=' the standard brakes wouldn't allow for a fat tyre.

 

Did anyone else notice any magical bits and bobs on these bikes? Any 36-spoke box-section wheels?
[/quote']

 

Well, lots of those box section rims with the gold valves (what are they called again?), but for the life of me I can't figure out why box section rims would be any better than deep section wheels like Cancellara, Hushov etc. were riding quite efficiently!  More old wives tales if you ask me....

 

...which is quite interesting seeing that Cancellara rode those special "aged" tubies.  He probably doesn't give a hoot what he rides and anyway, he punctured in Vlaanderen on those tubbies, so they can't be that good.

 

The cantilever brakes are obviously for mud, so not many used it, but the brake handles on the handlebar is a great idea.  Going downhill on the cobbles you can do with brakes on top of your handlebars believe me.  Last thing you want to do when you are bouncing like your in a rodeo is move your hands to the drops...
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Specialized Wins 3 in a row...

 

Boonen swaps bikes and went backwards...

 

Is it about the bike? Or is Cancellara just a beast!!

 

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Well' date=' lots of those box section rims with the gold valves (what are they called again?), but for the life of me I can't figure out why box section rims would be any better than deep section wheels like Cancellara, Hushov etc. were riding quite efficiently!  More old wives tales if you ask me....

 [/quote']

 

Box section rims to behave differently. It is not all that obvious but there is nevertheless a difference.

 

A box section rim has less material and is therefore less stiff. It is easily observed by squeezing a box section rim (rim only) like an old-time Bullworker. It goes oval. Try that with a deep section and you come short, it just about doesn't give at all. A Zipp 404 rim on its own is quite remarkable. I sit on it (74 kgs plus breakfast) and it hardly flexes.

 

In use the difference is that the box section rim gives over a larger area, recruiting more spokes to carry (give with) the load. This means less fatigue per spoke but also a less stiff wheel. The compliance of a 32-spoke box section wheel is in the 0.5mm range whereas a Zipp 404, probably one or two decimals less.

 

Further, if you use thinner spokes like say Revolutions, even more spokes would be in the load affected zone at the same time, improving wheel durability even more.

 

Does this make a difference over one race where fatigue breaks shouldn't really come to play? No. So you are right, old wive's tale.

 

 
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Are both sets of brake levers connected here? If so, how do the cables connect together to a common calliper?

http://cdn.mos.bikeradar.com/images/news/2010/04/12/1271062594900-g05qtiwsnemj-850-65.jpg

 

 

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Saying that Cancellara doesn't give a hoot is a laugh, these guys take their equipment very seriously.

 

All tubbies are "aged" in the pro circuit, and the box rims have more "give" in them so that the tyre is less likely to snakebite, and what wheels was cancellara on at flanders and roubaix? carbon zipp 303's...
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each lever controls a caliper and the lever pushes the outer housing away from the lever hence activating the brakes

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Rubber is the best shock absorber' date=' look at the original Austin Mini there was nothing fancy just a big block of rubber as shock absorbers, and the car is still touted as one of the best handling cars ever built! of course an insert will work...

 

When Bonnen won he was on pretty much the same bike.

 

I read an interview with Radioshack's head mechanic and he said the best bike for Roubaix is a standard machine, with a little more clearence for mud and old school standard wheels with spoke washers...
[/quote']

 

Rubber is a shock absorber. Not the best, but it does offer compliance under compression.

 

Zerts: I don't think many people have thought this through. Lets look at a zert in a seatstay or fork blade. Effectively the blade/stay is still one solid unit  with an "eye in it". If you apply shock to the one end of an blade like that without he Zert with with the eye, at an intensity of X Joules, you'll get X Joules out the other side. If you now insert the zert, you'll still get X Joules out of it (minus inertial absorbtion due to the zert's mass).

 

The zert does not separate two solid members as in the Mini's suspension. It simply hangs around and thus plays no active role. In other words, it is not a suspension component.

 
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All tubbies are "aged" in the pro circuit' date=' [/quote']

Now this is the type of lore I was referring to. This arcane old superstition has no foot in science.

 

 
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Well' date=' lots of those box section rims with the gold valves (what are they called again?), but for the life of me I can't figure out why box section rims would be any better than deep section wheels like Cancellara, Hushov etc. were riding quite efficiently!  More old wives tales if you ask me....

 [/quote']

 

Box section rims to behave differently. It is not all that obvious but there is nevertheless a difference.

 

A box section rim has less material and is therefore less stiff. It is easily observed by squeezing a box section rim (rim only) like an old-time Bullworker. It goes oval. Try that with a deep section and you come short, it just about doesn't give at all. A Zipp 404 rim on its own is quite remarkable. I sit on it (74 kgs plus breakfast) and it hardly flexes.

 

In use the difference is that the box section rim gives over a larger area, recruiting more spokes to carry (give with) the load. This means less fatigue per spoke but also a less stiff wheel. The compliance of a 32-spoke box section wheel is in the 0.5mm range whereas a Zipp 404, probably one or two decimals less.

 

Further, if you use thinner spokes like say Revolutions, even more spokes would be in the load affected zone at the same time, improving wheel durability even more.

 

Does this make a difference over one race where fatigue breaks shouldn't really come to play? No. So you are right, old wive's tale.

 

 

Thought so!  Thanks for the explanation Johan. 

 

Ambrosio, that's what those magic wheels are called!
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regarding zerts. I suspect that what they do do is to reduce resonance, whether that is even an issue I dont know.

 

 

 

Agree with JB They will do squat to improve impact absorbtion.

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Rubber is the best shock absorber' date=' look at the original Austin Mini there was nothing fancy just a big block of rubber as shock absorbers, and the car is still touted as one of the best handling cars ever built! of course an insert will work...

 

?

 

When Bonnen won he was on pretty much the same bike.

 

?

 

I read an interview with Radioshack's head mechanic and he said the best bike for Roubaix is a standard machine, with a little more clearence for mud and old school standard wheels with spoke washers...
[/quote']

 

?

 

Rubber is a shock absorber. Not the best, but it does offer compliance under compression.

 

?

 

Zerts:?I don't think many people have thought this through. Lets look at a zert in a seatstay or fork blade. Effectively the blade/stay is still one solid unit? with an "eye in it". If you apply shock to the one end of an blade like that without he Zert with with the eye, at an intensity of X Joules, you'll get X Joules out the other side. If you now insert the zert, you'll still get X Joules out of it (minus inertial absorbtion due to the zert's mass).

 

?

 

The zert does not separate two?solid members as in the Mini's?suspension. It simply hangs around and thus plays no active role. In other words, it is not a suspension component.

 

?

 

Perhaps you should play something like a guitar to try and understand something like frequency or vibration damping.

 

Same as in a sound studio where damping and Helmholtz resonators are used to (dampen, break, make smaller or what ever term one feels like using) the sound nodes in particular lower frequencies.

 

Nobody has ever made claims that these Zerts act as a suspension device.

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Saying that Cancellara doesn't give a hoot is a laugh' date=' these guys take their equipment very seriously.

 

All tubbies are "aged" in the pro circuit, and the box rims have more "give" in them so that the tyre is less likely to snakebite, and what wheels was cancellara on at flanders and roubaix? carbon zipp 303's...
[/quote']

So box rims have more "give" and Cancellara takes his equipment "very seriously".  Yet he does not ride with box section rims, but with inflexible carbon rims....  So is he stupid or are the other riders stupid?  You said they all take their equipment very seriously, so they should be on the same rims right?  Somewhere something isn't adding up here...

 

A year or two ago nobody would have dared to ride a cobbled classic with carbon rims yet now that myth has been shattered by Cancellara and co.

 

I rode the Vlaanderen cobbles with my 404's and I promise you I did not get any snakebites (and I am heavy!).  People get snakebites because they run their tires underinflated, not because of the type of rim they use.

 
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regarding zerts. I suspect that what they do do is to reduce resonance' date=' whether that is even an issue I dont know.

Agree with JB They will do squat to improve impact absorbtion.[/quote']

 

I suspect the resonance issue as you point out, is what it will come down to when we get the Specialized engineer in a corner. However, resonance is a funny thing. It is absorbed by the largest damper in the system, in this case, your hands or arse. If the largest damper in the system reduces resonance, then little additons like zerts don't do anything additional.

 

They could absorb resonance, but then they have to have good mass and must be on the nodes. I haven't weighed a zert yet but I think it weighs very little and therefore has no effect there in no-mans land far away from one of the nodes in the resonating system.

 

Bontrager, I think, has a similar gadget they put in a handlebar. The reps go around to bike shops and demonstrate it by dropping a naked handlebar on the ground and pointing out how it rings and tings. They then insert one of these little Bontrager zert into the bar, drop it and it makes one solid clang and then shuts up.

 

They don't go any futher than that and just conclude the sale there and then. They should actually take that same bar, dress it up in bar tape and a set of STIs and then drop it. It will be even quieter. Adding a zert into this system does nothing since the largest damper is the tape and STI.

 

Motorcycles have zerts too. They have heavy weights at the end of their handlebards, protruding past your hands. This is to dampen the vibrating bar-end. They work very effectively, but only 'cause they're heavy and they are positioned correctly.
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I like the Felts from GARMIN with oldschool Dura Ace 9800 on them.. haha. Bikes look a lot crapper but guess DA 7800 didn't run that long for nothing..

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Perhaps you should play something like a guitar to try and understand something like frequency or vibration damping.
Same as in a sound studio where damping and Helmsholtz resonators are used to (dampen' date=' break, make smaller or what ever term one feels like using) the sound nodes in particular lower frequencies.
Nobody has ever made claims that these Zerts act as a suspension device.[/quote']

 

Best to use the internationally recognised term. That way we're all on the same page.

 

As far as I understand resonance, you you damp frequency, only amplitude. Perhaps your experience with Helscholtz resonators taught you otherwise. Please share.

 

I thought I explained how dampers work and why a smaller damper has no significance. Maybe your post preceeded it. Have a look.

 

I do think there was an implication that zerts act as suspension devices, even more so in this discussion where there is confusion between vibration damping and suspension damping.

 

 

 

 

 
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