Treker

Hi all,

How much shock/vibration dampening does a full carbon fibre bike afford over an all-aluminum bike? Not owning a C/F bike myself, I can't answer that and searching the forums, I wasn't able to really discern an answer.

A good friend has stenosis, a narrowing of the spinal column, that's applying a wee bit of pressure on his spinal cord causing some sometimes tingling in his left hand. He's okay to cycle for an hour or two but he refrains from anything longer for fear of applying too much stress over a prolonged period.

He's currently on a 2005 Trek Cyclocross XO1 but he's aware that C/F affords vibration dampening. Would a new bike make a significant difference or would it be a crapshoot?

Cheers

timmhaan

i don't think it would make too much of a difference. it's all pretty subtle. i think you could get similar results by letting some air out of the tires to be honest.

BladeGeek

It is hard to answer "how much" but one can say it does dampen vibration some.

SDRider

It depends on many things, such as construction of the frame, geometry, weave of the carbon fiber, etc.

I'd try a few of them out on extrended rides and see which ones feel the best.

GuitarWizard

It depends....

My Trek 5200 (full carbon) gives a noticably "cushier" ride than my Trek 2500 (aluminum frame/carbon fork). Tire pressure and wheels can also play a big part in overall comfort as well. Many people who aren't too heavy to begin with will pump their tires up to the max rating of the tire, and having tires that are pumped up too hard will sometimes make a bigger difference than frame material.

He should go test ride some bikes....all carbon bikes are not made equally. Some are very stiff. The Trek OCLV series seem to offer a pretty comfortable ride, IMO.

rollin

I have a 5200 and having ridden a similarly spec'd alu Trek I agree with GuitarWizard completely

There was a Cannondale road geometry bike with some kind of an elastomer "suspension" a few years ago - that might be one way to go

Treker

Thanks to all for the very quick replies and advice as well as to any others that may/will post. I'll be sure to point him to this thread.

Proximo

My full carbon RS is noticeably smoother on bumps than my aluminum framed Sequoia, even with it's carbon fork and seatstays. That's with the exact same wheels, tires and tire pressure.

oboeguy

I experienced a world of difference between my new, full carbon Scott CR1 and old 525 steel Lemond (admittedly, a much lower class of bike).

atomship47

i went from an aluminum hybrid to a full cf roadie. i chose full cf for exactly the reason you post.

my take is this, you can change the ride and amount of vibration many ways...larger tires, less air pressure, etc....i think the real benefit of full carbon is with high frequency vibrations....vibrations that you don't necessarily feel at any given moment while you are riding.....however, lets say you rode 50 miles, these higher frequency vibrations add up over the course of the ride. i'm thinking the real benefit of full cf is by reducing the fatigue and discomfort you would feel late in your ride (or after your ride).


if that makes sense at all

waterrockets 

So are we talking about actual dampening here? Or are we just talking about compliance?

Dampening is a characteristic of CF, where kinetic energy is converted into heat and sound. Compliance is an engineering characteristic, independent of frame material.

halfspeed

Unless he has put 23mm tires on his cross bike, CF will offer no advantage whatsoever. The fatter tires on the cross bike will do far more for vibration damping than any frame will.

CastIron

Bingo.

Bacciagalupe

If your friend's back trouble is something that could be aggravated by cycling, maybe he should look into a recumbent. That will be MUCH better for his back than even a CF frame with wide tires. Much faster on the flats too.

umd

It doesn't make a huge difference on reasonable roads. Most city/rural roads probably fall into this category. However, on really crappy roads it makes a huge difference. There is a not very well maintained mountain road in Santa Barbara (Gibraltar and Camino Cielo for those familiar with the area) that I used to ride regularly. On my AL bike it was really bad. On my CF bike it is much better. Still bad, I mean its not a magic carpet or anything, but much smoother than the AL.

ericgu

Well, it absorbs very small bumps well - rough surface feels less rough. It also take a tiny bit of the edge off larger bumps, but you still get a big jolt.

Thats on my Madone 5.2

damocles1

+100

I have two carbon road bikes (Ridley Damocles and Pedal Force RS) and the ride characteristics are night and day.

Not all carbon rigs are created equal...

ezee

Ok,
So, from these 2 bikes, which one is "night" and which one is "day"?

Psimet2001 

Tires make a bigger difference on vibration dampening than a frame does....unless that frame has a suspension built into it. Keep that in mind.

thelazywon

+1, do tell

schnee

My Giant OCR2 (carbon) with 23mm high PSI tires is waaaaaaay nicer and easier on my hands and nethers than my Kona Jake the Snake (aluminum) with 34mm low PSI tires. The Jake has slacker angles and a shorter top tube, which makes it theoretically even better, but still the carbon feels like I'm riding on a cushion of air. I feel the big jolts like seams in the road and rocks, but the texture of the concrete seems to fade away to nothing.

Shut up & ride

Clearly none of us can speak to the impact that the switch would have on your friend given his particular medical condition. Several people here replied that the difference would be small. For me, it made a big difference. I have a bad elbow from a sports injury and 3 subsequent surgeries. Not much cartilage left. The compression forces during cycling impact it. I tested a lot of bikes and decided that FC was absolutely the way to go for me. Still very happy with that choice. That said:
- I agree that it depends on the condition of the roads he rides. On smooth roads it won't make much difference anyway.
- I agree that they're not all the same. He's gotta try some. If test rides aren't enough, he can rent current models for a day or two.

pdq 5oh

My Trek Pilot 5.0 rides way smoother than my past aluminum bikes. Trek offer a Pilot with an elastimer suspension in the rear.

sogood

Comparing my present Ridley Damocles and Bianchi alu bikes, the CF definitely makes an appreciable difference in the road shock department. There are certain section of the road way that I am very familiar with, the difference riding over them can be pretty dramatic. But it does not make my Bianchi any less fun to ride, just different characteristics. And is it worth the thousands of dollars in price tag difference? I'd say no if this is the only parameter of comparison.

asmallsol

As others mentioned, I noticed a decent gain in cushy-ness upping to a carbon frame.

I have a 2005 Specialized S-Works tarmac and before I had a 2003 Marin Columbus Steal/carbon rear stay, and the ride is night and day. road buzz is reduced dramaticly, and bumps/cracks don't really send that shock wave as they did on my old bike.

Best way to compare it would be I used to have a built up track car, with great suspension. It handled great on a road course, but the ride was very stiff. My dad has a new Mini cooper S and with handling close to my old track car, but over bumps it just feels more solid. Yea you still feel them, but its just not as rough. The ride quality is just better.

To add to that, my new bike is considerably more stiff around the BB area. Its great what Material Science does to the bikes.