My experience with Carbon

[jeffc]

Hi, I come from a Mtb background last few years and am buying my first roadie in some 10 years for training and longer rides - So far I test road an alloy Giant TCR with ultegra - which was awesome - fast stiff - downside was that you felt every bump. Then I tried a used full carbon $5k+ Avanti Quantam 3 with durace upgrade. It was very compliant/comfortable on bumps but slow - I was shocked - felt like my dualie mtb bike in terms of getting up some speed. My question; are lower spec carbon bikes ALL like this?
On my shopping list was a CAAD9-5, Giant TCR Alloy, or a discounted Specialized Tarmac Elite carbon - I am tempted to go the Giant as I get Ultegra and the stiff frame.
Cheers
Jeff

[JV911]

what will you be using the bike for?

if it is purely a crit bike then alloy might be the way to go. however if you are going to be doing 100km rides on average roads every week then carbon could be better.

not sure how the quantum 3.0 differs to the quantum team but the team get some of the best review i've ever read.

[sogood]

Then I tried a used full carbon $5k+ Avanti Quantam 3 with durace upgrade. It was very compliant/comfortable on bumps but slow - I was shocked...

Feel can often be deceiving!

Otherwise there's a lot more to speed efficiency than the bike frame. Wheel, tyre pressure, bearing, bike condition etc.

[drubie]

How did you measure "slow"?

[jeffc]

Hi,
Thanks for taking the time to reply - forums are great to hear from the 100's of years experience people have and i don't have the time to test ride tonnes of bikes. to answer the q's -Slow as in the same as my mtb on the road. It was like the brakes were on. I was told it had a cheap set of wheels on it and that might account for the mushy feeling. I will have a ride of another carbon frame to see.
I get that carbon is lighter, stiffer where you want it for steering accuracy etc and compliance wise it was perfect - just didn;t accelerate like the alloy - greater effort less speed.
My primary use is training but I want something quick/stiff/efficient as I could just put some slicks on my MTB

[sogood]

Clearly your experience is contrary to everything out there or pro racers wouldn't be using CF framed bikes. As a minimum, there's no difference in speeds of two comparable bikes of CF vs Alu construction. You are probably better to put the blame on other components and service condition differences b/n the two bikes.

[drubie]

Noodly wheels can make a bigger difference IMHO than frames can. However, some cheap wheels are nice and stiff (Fulcrum for example). They can change the whole feel of a bike.

BUT - unless you're using a stopwatch, those feelings can be deceptive. When I upgraded to a carbon frame, it was so much smoother than the alloy one it confused the hell out of me.

[JV911]

forgot to mention:

are lower spec carbon bikes ALL like this?

i wouldnt call a quantum 3.0 "lower spec" either

[jeffc]

Just rode a Spec Epic and it was much better - very stiff. But readin the replies i am thinking its a perception thing then - the lack of road vibrations that makes it feel slower. If you guys reckon theres an adjustment coming from alloy then I will keep trying until I get one i like

[Missy24]

Hi, I come from a Mtb background last few years and am buying my first roadie in some 10 years for training and longer rides - So far I test road an alloy Giant TCR with ultegra - which was awesome - fast stiff - downside was that you felt every bump. Then I tried a used full carbon $5k+ Avanti Quantam 3 with durace upgrade. It was very compliant/comfortable on bumps but slow - I was shocked - felt like my dualie mtb bike in terms of getting up some speed. My question; are lower spec carbon bikes ALL like this?
On my shopping list was a CAAD9-5, Giant TCR Alloy, or a discounted Specialized Tarmac Elite carbon - I am tempted to go the Giant as I get Ultegra and the stiff frame.
Cheers
Jeff

Try the 2010 Cannondale Six Carbon 3... stiff bike

[mtb101]

Then I tried a used full carbon $5k+ Avanti Quantam 3 with durace upgrade. It was very compliant/comfortable on bumps but slow - I was shocked

if a bike is slow, it's either heavy - say well over 9kgs (in comparing cutting-edge race bikes i.e. 6.2-8kg) 3.0 is approx 7.8kgs, or has heavy wheels (3.0 wheels are 1.8kgs mid range weight) or frame is too flexible - if you look closely at the 3.0 it is stiff (large headstem 1 1/8 - 1 1/2, large bottom bracket - BB86 dura-ace, big downtube 70mm, so in summary it comes back down to the engine driving the bike. Try a ride again, try a climb or descent or a longer ride, think you'll change your mind. Yes I own a 3.0 and my main riding is mtb, the 3.0 is the best bike I've ever ridden, (been riding a long time) and had many bikes including the euros, finally you don't need to pay $5k, try below $4k for 09 model. And if you want to have a mtb vs roadie drag, let me know, I know what sort of bike I would be on.

[aeroslave]

Firstly, all frame materials can be affected by the geometry that they have. The so-called "feel" of the bike is more dictated by the type of tyres and the geometry of the bike than anything else.

Secondly, Carbon framesets cannot be judged solely as a material classification. In metal materials such as steel, titanium, aluminum and all other materials requiring welding and hydroforming techniques, geometry and craftmanship in welding etc etc are the biggest factors as the metals are consistent with their class. What I am trying to say is that 3.5/6 Titanium frames for example will always exhibit the same characteristics and its the design, thicknessof the diameter and geometry that will dictate its "feel". Butting is the closest thing to the lay up process in carbon fibre for metals.

With carbon its an entirely different beast. First the quality and stiffness of the carbon fibre could range from the noodle flexy type to the bone jarring super stiff carbon fibre used by the sprinters. Then you have the quality of the resin used to keep them together.
Then you have the lay-up design where engineers and specialist actually try to keep their designs secret until it reached china's assembly line. The lay up design could vary from the uber effective designs to the fake chinese rip offs that are guaranteed to shorten the lifespan of your front teeth

So really when you experience a carbon frameset, you are experiencing that company's lay up design and definitely will not represent majority of the other bikes outside.

It can be done with other materials but with carbon fibre..its basically easier to mimic or create the characteristic and shape that you want in excellent stiffness to weight ratio. Simple reasons why its the preferred choice for competition.