Real life benefits of carbon wheels?

[rando]

Originally Posted by ripvanrando

I recently rode cross country with carbon front rims and aluminum rims on the rear.

I for one have no interest in the low speed travails of a four wheeled recumbent rider. Failing a long winded explanation I'll conclude their was irreducible logic used in every other specification from stem to stern.

Originally Posted by ripvanrando

I wondered if the rims were so hot that the rain just sizzled off them.

Yes, that is most likely the part of this exaggerated tale you most embellished.

[ripvanrando]

I

Originally Posted by rando

I for one have no interest in the low speed travails of a four wheeled recumbent rider. Failing a long winded explanation I'll conclude their was irreducible logic used in every other specification from stem to stern.






Yes, that is most likely the part of this exaggerated tale you most embellished.

Maybe I need another latte on my break from today's ride because I don't understand what you are saying. I'm telling you that in the rain on high speed descents during the Transam bike race that my carbon rim braked better in the rain than the aluminum rimmed rear. Here is a photo at the top of a pass in Colorado where it rained on the descent that I took at more than forty mph. As you can see the front rim is carbon

[Waldo]

As I age and get fatter and slower, lightweight and aerodynamic carbon wheels allow me to chase my younger, fitter self. And my 40mm carbon Fulcrums seem to be worth up to 0.5mph of average speed on a three-hour ride, though some have suggested that I try harder while riding these wheels, which is OK too.

[summilux]

Originally Posted by FlashUNC

Fwiw, my Hyperons brake slightly worse than my Shamals, but it ain't by much.

But Hyperon braking gives you that "Coming out of lightspeed" sound that cannot be duplicated elsewhere

[Mark McM]

Originally Posted by benc

They're fast. Borrow a pair or test out some loaners from your LBS. There will likely be naysayers around here but I suggest you make your own opinion.

I'm 5500 miles in on a pair if Chinese carbon clinchers. 200+\- miles a week of shotty intown Atlanta roads. When I ride other wheels, I miss my carbons. I'm a roadie racer with a 15# bike.

I have a friend who is convinced that his new ceramic bearing bottom bracket makes him 2 mph faster. When I try to tell him that drag in all the bearings combined adds up to maybe 1% of the total drag (so even if all his bearings had zero drag he'd only go a fraction of a mph faster), he just won't hear of it. He knows those ceramic bearings make him faster, and that's all there is to it.

[rando]

Originally Posted by ripvanrando

I
Maybe I need another latte on my break from today's ride because I don't understand what you are saying. I'm telling you that in the rain on high speed descents during the Transam bike race that my carbon rim braked better in the rain than the aluminum rimmed rear. Here is a photo at the top of a pass in Colorado where it rained on the descent that I took at more than forty mph. As you can see the front rim is carbon

I'll play along like it's funnier if you have to explain it.

- 'rims' denoting multiple front and rear
- unposted but captioned photos claimed to be taken at a high rate of speed on a challenging descent. In the rain no less!
- seemingly unaware of the differences in stopping power between front and rear brakes. Particularly where said forces are even heavier in favor of the front brake (hint: going downhill)

[Mark McM]

As with anything else, there are pros and cons to carbon wheels. In particular, due to their different manufacturing processes, it is easier to produce carbon rims in aerodynamically efficient shapes than aluminum rims, and also to produce those shapes at a lighter weight. That has to balanced with their higher cost, less consistent braking, and greater tendency for heat sensitivity (particularly for carbon clinchers.

I do have a set of carbon/aluminum Flo 60 wheels, and here's is my use for them:

I'm still actively racing my bike, but now that I'm in my 50s I'm having a little more trouble keeping up with the younger guys. On the other hand, at this stage in life I have a little more earning power than some younger guys, so I can afford some more expensive wheels (although Flo wheels are on the inexpensive end for carbon wheels). I'm certain that the Flo wheels are faster than traditional aluminum rim wheels would be in the type of racing I do (primarily criteriums), but not by much. It is a matter of incremental improvement, and is only a small portion of the increment improvements I use.

Years ago, I raced on a steel framed bike with traditional wheels. In addition to the afore mentioned aero wheels, I now also race with aero frame bike (which even has aero drop bars), use low rolling resistance tires which have been matched to the aerowheels (Flo did a study of the best tires for their wheels), I use aero water bottles, and wear an aero road helmet and skinsuit. It is true that all of these add only marginal improvements. But when all of these things are added together, I figure I get a speed gain of about 1/2 to 2/3 of a mph (and the skinsuit and helmet are probably most of that).

When I'm not racing, I still ride a traditional steel bike with traditional aluminum rim wheels, with traditional bottles, etc. Do I notice the performance loss? Not really; I'm sure its there, but its small enough to not notice without a stop watch (or other competing racers). However, the traditional equipment does tend to be more practical for everyday riding.

[ripvanrando]

Originally Posted by rando

I'll play along like it's funnier if you have to explain it.

- 'rims' denoting multiple front and rear
- unposted but captioned photos claimed to be taken at a high rate of speed on a challenging descent. In the rain no less!
- seemingly unaware of the differences in stopping power between front and rear brakes. Particularly where said forces are even heavier in favor of the front brake (hint: going downhill)

You call me a liar (a slow one at that) and now you correct my grammar and make some more wild assumptions about how I determined the braking force was better on the carbon rims vs. aluminum rims. I noticed some grammatical errors on your post but let them slide.

You seemingly are unaware that the stopping power differential between front and rear is due to weight over the front wheel and the ease with which a real wheel can lock up is due to that weight shift. In heavy rain neither wheel can be locked on my rig, so, braking force comparison is only related to the forces at the rim and not whether the tires lock up. I could squeeze as hard and as long as I wished on the rear brake and the braking force was rather moderate but there was no way it was going to lock up. The front brake on the carbon rim would have an initial momentary take up (unless it had been used recently and I presume the heat buildup) and then the braking force was very good.....not quite as good as in the dry but darned good. Carbon rims get very hot to the point you will get burned if touch them after hard braking.

I have no idea why the picture did not post but you misconstrue the intend of the picture, it was to show a carbon rim front and aluminum rear. I thought this was what you wanted to see.

Since you are also a Randonneur and obviously a very fast one, lets met up. I had a goal of doing my full series in less than 50% of the allowed time but am finding I need a partner to do the 600K in under 20 hours. What do you say? I could use help and would be more than willing to help you out.

Others have also said carbon braking is pretty good in the rain. You can choose to believe or not.

Let me know if you want to do that 600K together.

[FlashUNC]

Originally Posted by summilux

But Hyperon braking gives you that "Coming out of lightspeed" sound that cannot be duplicated elsewhere

The Boras are wayyyy better at that.

[false_Aest]

In before the lock.

[sg8357]

Why Carbon rims ?

Carbon rims are poor with rim brakes,
so you need disc brakes, cable discs are as bad
as cantilevers, so you need hydro discs,
the hydro mechanical shifters are clunky and uncomfortable,
so you need a electronic group with hydro shifting, your
frame isn't setup for disc brakes & electronic, so you need a new frame.

That is why carbon rims are the greatest thing in the cycling industry.

[weisan]

Looks like I will be jumping into the fray of carbon wheels pretty soon. A buddy that I ride with in our group rides had just upgraded his wife's bike with a new set of carbon wheels so he is offering her older set of Reynolds Assault for me to try them out. Will report back.

[rustychisel]

Originally Posted by weisan

Looks like I will be jumping into the fray of carbon wheels pretty soon. A buddy that I ride with in our group rides had just upgraded his wife's bike with a new set of carbon wheels so he is offering her older set of Reynolds Assault for me to try them out. Will report back.

Yes, report back if you survive the experience...

[sokyroadie]

I bought a like new new set of SLG Reynolds 32's tubular with basically new Vittoria high $$ tires for $500.00 from a forumite. The wheels weigh around 1150g - In my mind they transformed the ride of the Ti Serotta that I put them on. The bike just feels much quicker and livelier.

I have had several other sets of carbon tubulars and clinchers, some deeper and some shallower - I much prefer the shallower, lighter ones - YMMV.

Jeff

[oldpotatoe]

Originally Posted by Mark McM

I have a friend who is convinced that his new ceramic bearing bottom bracket makes him 2 mph faster. When I try to tell him that drag in all the bearings combined adds up to maybe 1% of the total drag (so even if all his bearings had zero drag he'd only go a fraction of a mph faster), he just won't hear of it. He knows those ceramic bearings make him faster, and that's all there is to it.

We had a customer who was second or third at a local grand fondo..he came in and asked for a complete ceramic upgrade..BB, hubs, even pulleys, cuz he said he would have won if he had ceramic bearings..true story..we did and took his $..and replaced the pulleys after one wet ride.