Hezz

This is possible. Although the brake pads are made to take quite a bit of heat. But I'm thinking that because carbon fiber is so poor a conductor of heat it may have caused the brake pads to get much hotter than usual. With an aluminum wheel the heat will go out through the wheel since aluminum is likely a much better conductor of heat than the brake pad is. So heat will take the path of least resistance. And the wheel having a much larger surface area than the brake pad can cool better in the airflow.

Hezz

My guess is that Armstrong had a strong influence on light bikes. Since he was always asking Trek for lighter stiffer bikes. He knew that to have an advantage on the climbs could be the difference of winning the tour or not.

One thing that I read the other day talked about how if the bike frame has the right compliance it is safer on descents because it sticks to the road better. But this might be at odds with total stiffness factor. I imagine that early aluminum bikes had really bad riding characteristics. It has taken the manufacturers several years to learn how to build good aluminum and carbon fiber frames and the approaches are different than with steel. The Italians pretty much had steel frame bike building down to an art form. And I'm sure that early aluminum bikes had horrid handling.

tkm

Guys--carbon fiber brake rotors already exist (expensive, but they do exist and work), so I have a seriously hard time believing that a carbon fiber bike wheel will explode or melt unless the wheel was just a complete piece of crap.

And don't airplanes use a carbon fiber braking system?

https://www.carbonfibergear.com/ferra...-brake-rotors/



For motorcycles:

bellweatherman

What I think he meant was that the glue on the carbon rims were melting, not the rims itself. Most pros use tubular rims and they have to be glued onto the rim. It isn't uncommon for glue to get warm and melt on these long mountain descents where there is a lot of braking. The danger is that the tire is not firmly held onto the rim and there is a higher chance of the tire rolling right off the rim in a corner. It has happened before.

UnsafeAlpine

That, I can believe.

stewardmike03

keep in mind that carbon technology is ever evolving as well...don't fool yourselves in believing that everyone got it right from the start. Could wheels have melted and gotten gummy? Sure. That in turn would have started a new quest to fine tune the carbon to be more resilient to heat. Common sense and mistakes is how lessons are learned. The first carbon tubed bikes sucked. The first aluminum bikes sucked. I'm sure the first steel bikes sucked too. With time comes advancement in science. You can get superlight steel frames now that are only as light as they are due to heat treating and alloying properties...that all took years of research and development. Same holds true for ANY material.

merlinextraligh

They tried to weigh it but the frame kept flexing over the scale to the point they couldn't get an accurate reading.

Ames

I bought new and still have a crica 1980 Motobecane Champion full Campy Tubular etc that is arround 20 lbs with the Super Record Alum and Ti clip pedals. It is lugged 531 Reynolds and they had just come out with 753 that was lighter by about 9 ozs and you could drill everything full of holes. Seventeen pounds was then but not reliable either. I also have an 09 P1 6.9 Trek Campy under 16lbs stock that can be brought down to under 13 with 13 lbs of $100 dollar bills.

Now the point: we are talking about 4+ pounds total weight loss since 1980 with all the material changes and engineering the pedal stroke to the road efficiency, and the more scientific training and we are not really going that much faster. Why? The basic road bicycle design is almost perfect.

daxr

I raced a 19 lb Klein in the mid 80's, running tubulars but nothing too special otherwise. Maybe someone won the worlds on a 23 lb bike after that, but it was apparently odd enough to get a mention in Winning.

boazmoss

You are so right,but , it ; ( reality) has become ------------------ inconceivable.

monosierra

True. Its a race to the 'bottom', so to speak, with all the companies boasting about shaving grams. Bragging rights, I think.

tigershark

LA says his bike in the '99 tour was 20 lbs. It's crazy how much things can change within 10 years.

https://www.trekbikes.com/us/en/bikes...eight_matters/

boazmoss

you mean a race to a lighter bottom,and shaving grams from the water bottles?

monosierra

Haha yeah. Some of the weight saving claims sound ridiculous. But as a post above pointed out, over the decade, minor weight savings have added up to something substantial.

Fat Boy

In all fairness, carbon-carbon brakes do not contain an epoxy. They are sintered under extreme heat and pressure.

The fun with carbon-carbon brakes is when you over-heat them, which can be done. They simply oxidize. What is the most common form of an oxide of carbon? Carbon Dioxide. They literally vaporize.

boazmoss

I agree with the notion that Italy had steel down to an art,and, my take for that reason would be:
1-The consideration of the simple fact that after a long climb comes a long descent.
2-On a descent when speeds go beyond 60kmph ,you want to feel your bike, your safety depends on it.
The term "technical descent" became a household term when pro riders descending the Alps or Pyrenees with a pocket book between their legs must do so just to stay in contention.Any non trained rider,rolling down at that speed with a 6.8kg bike would be very unsafe. He would probably burn the brake pads just to maintain control.
Sadly that's what pros have to put out nowadays .
Veterans seem to be very happy with their 20lbs rigs.

dolophonic

This is actually a problem, Reynolds crbon clinchers are known to have this happen.
The rim de-laminates or warp's at the breaking surface.
I have also seen the same on an Edge clincher.

VA_Esquire

Im wondering when they are going to start making their drinks lighter :sarcasm: