The Weight of Pro Bikes
 

Looking through a Winning magazine from 1991. They had a feature on Gianni Bugno's World's winning bike. A lug-less steel Moser with Dura Ace & 36 spoke hubs that weighs in at 23 pounds 11 ounces! Winning points out that the 36 spoke wheels are probably not those ridden in the worlds but still that makes for a heavy bike.
Doe's anyone have any info on pro bike weights & how they evolved down to todays sub 16 pound bikes?

Carbon fiber, lighter components, 200 grams shaved here and there every season.

^ development in carbon fiber has been probably the greatest advancement. it started with frames, but now look at it, carbon everything... bars, stems, brakes, rims, spokes, hubs, cranks, BBs, seatposts, saddles, even deraillers. i think the only thing i haven't seen carbon fiber on yet is the chain.

there are obviously other factors and metal alloy parts have still gotten much lighter, but carbon is at a point where it is lighter than almost any (safe) steel or alum parts.

Michael Barry wrote in Velonews about CF rims melting while descending on an 8 hour 110 degree stage at the last Giro. Hard to believe but...

That's nearly impossible to believe. Carbon fiber is not plastic. There may have been a major malfunction of the resin, but it would take an amazing screw up for that to happen. I'm more worried about aluminum rims heating and warping than I am of carbon fiber rims failing due to heat.

Actually that's not true. Carbon fiber is a mixture of Epoxy resin and carbon fibers. And epoxy is considered a type of plastic. Also carbon fiber transfers heat poorly. So once the heat builds up in the wheel it probably has a hard time getting rid of the heat.

Sounds a little heavy to me. By the late 70's, early 80's it was pretty common to have sub 20 lb bikes.

Ah, more from 1990 winning.
Greg Lemond's Worlds TVT Carbon, Mavic, 28 hole wheels, 18-19 lbs.
Katrin Tobins's Huffy, True Temper RSX, D-A, 28 hole, 20.5 lbs.
Sean Kelly's Concorde SLX, C-Record, 32 hole, 21 lbs.

Does it mean the riders back then are stronger?

Only if they completed climbs in the same or better times as today with a heavier bike+rider, right?

"Carbon fiber" *is* plastic, reinforced with fibers of carbon.

Yeah, that does seem a bit heavy. In 1990, I had a Scapin with Shimano 600 Ultegra, and I think it weighed in under 21lbs. That same year, I remember a fellow club member having a Vitus Carbon 9, and when I picked it up, I was impressed by its feathery light weight; I think it came in at the 18 to 19lbs range. Not too bad at the time.

Cycling is a sport that if you had a time machine and grabbed a guy off his bike in like 1950 and put him on todays bike, he would compete. In many sports that is not true. Stronger, not sure, average speeds were slower but then again the route was often much longer.

Sort of. While the resin used to reinforce cf is considered a type of polymer, it is unlike that of run-of-the-mill plastics. Resin is usually a thermosetting plastic meaning it cures at a very high temperature, usually above 200C. This gives them an incredibly high melting point. This is one of the reasons cf can be used in high temp applications. Traditional plastic usually has a melting point of >150C.

Also pro bikes are usually regulated by the UCI to weigh more than the state of the art would allow for "safety". Current minimum weight is 6.8 kg which is like 14.9 lbs, whereas during non-UCI races there are bikes weighing in at 10-11 lbs or something crazy like that.

I hate to get nit picky but in all the engineering books that I have studied Thermoset resins are still considered plastics. Also, there is a range of temperatures that the resin cures at depending on the type of resin. But curing and melting are different things. Thermosets do not harden by cooling off but by chemical cross linking which occurs at the curing temperature. And while some thermosets don't actually melt in the same way that thermoform plastics do. They can still deform much more at higher temperatures.

As far as I know general type epoxies are good up to around 600F of continuous temperature. And some higher temperature ones can go higher. Most thermoforms melt at around 400F. But would have a much lower continuous use temperature.

I'm not searching but there was a good thread somewhere recently on BF that pictured a TdF winner and his bike from about each decade. It really wasn't until lately that the bikes went much under 10kg. I was surprised. Even Mig's pictured bike was over 20#.

Here's from this article:

While the climbs were physically exhausting the descents were mentally exhausting. Descending on roads that were never long and straight, but rough, graveled and winding we finished the stage with sore arms from the hours of braking. By the end of the day the pads were worn thin and my hands blistered. Like pigs nearing their end at the slaughterhouse, our brakes squealed under the pressure of the heat and load as we approached each switchback. On the descents carbon rims melted and tires exploded. The wear of the day was evident everywhere.

All should read that Michael Barry article. It's a good look at just how difficult racing can be.

I suspect he meant that the brake pads melted rather than the rims.

Regards.

FWIW, there was an aluminum Barra in the 1948 TdF that weighed in at 17.8 lbs.

Light bikes have always been available to riders but lightness has not always been the most important factor when choosing a bike. For example, Coppi's '52 Bianchi had steel cranks yet TA had been making lighter aluminum cranks for over a decade. Why the heavy steel cranks? Most likely Coppi thought the "better" Q-factor of the steel made more difference than lightness.

Lightness was not the cyclist's wet dream in the past as it is today.

23-11 sounds heavy. I have an SP tubed Merckx Pro from the mid eighties w/SR and 36 spoke Nisi Tubulars that doesn't weight that much. If I remember correctly it comes in just over 22. Most the pro's of that era were on bikes just under 20.

With regard to the off topic discussion of carbon rims. From an engineering stand point they are made from FRP (fibre reinforced platic) in this case the fibre is "carbon" but the binding material is still considered plastic. And yes, depending upon the resin used the melting point can vary.

See Jan Heine's recent book, "The Competition Bicycle." It's a full history of actual racing bike, and he weighed each bike complete with saddles and pedals. Except for a few rare track bikes, and a few bike with exotic parts or drilled-out components, most of the classic racing bikes were well over 20 ponds:

Some weights from that book:


Sean Kelly's 1991 Concorde: 22.8 lb
A. Hampsten's 1988 Huffy (actually a Landshark): 22 lb
Greg Lemond's 1981 Gitane: 22 lb.
E. Merckx's 1974 deRosa: 24.3 lb.
B. Waddell's 1965 Cinelli Supercorsa: 25.3 lb (this was a bike bought retail by a college student who was racing at the time)
1948 Wilier Tristina: 23.1 lb
1910 Labor Tour de France: 29.3 lb

Earlier thread here:

http://www.bikeforums.net/showthread...+heine+bicycle

To clarify about the melting issue: there are 2 basic kinds of plastic: thermoplastics and thermosets. Thermoplastics melt and are used in processes like injection molding. Thermosets are plastics in which the molecular bonds form by a chemical reaction, epoxy being one example. The cured resin will burn and char before reaching the melting point.