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Softer ride: caad7 vs carbon seat stays? Is Caad7 fragile?(23 posts)

Softer ride: caad7 vs carbon seat stays? Is Caad7 fragile?snowman3
Mar 10, 2003 7:17 PM
I'm shopping for my 1st quality road ride and don't have a very good "seat of pants" metric apparently. A $1600 C-dale R1000 caad7 felt about the same as the Klein Q-Carbon and some other $1500 bikes with carbon seat stays.

Eventually I'd like to do some 60-100 mile rides, so I'd like something that will soak up the vibration. They all felt about the same in the parking lot, so does anyone have some insight as to which one feels better after 2hrs of riding?

Steel had the best ride, but it just sucked the life out of my when having to accelerate and therefore was a turn off.

Also, the very thin tubing of caad7 raised my eyebrow. I don't know much about the typical roadie wipeout. Is caad7 fragile compared to most other AL bikes ... or will any wipeout pretty much toast the bike anyhow? What if its leaning against a tree and falls over, etc. or other low speed bumps-n-bruises.

Thanks for your help.
re: Softer ride: caad7 vs carbon seat stays? Is Caad7 fragile?KellyCross
Mar 10, 2003 7:42 PM
Caad7 is extremely strong. i had a early season crash last year & the frame came away in perfect condition, the fork did get broken but no damage to the frame. the ride of it is very compliant & a very good choice for long rides. i think that carbon seat stay bikes are a little hyped, how can you expect compliancy out of such a short section of carbon fiber especially one thats straight. c'dale has the swoopy stays so they can flex, you get very little flex out of a straight tube & then the longevity of something that's bonded together is questionable. the caad7 is the way to go, i love my r5000 anyway.
re: Softer ride: caad7 vs carbon seat stays? Is Caad7 fragile?Nessism
Mar 10, 2003 8:22 PM
I don't doubt the overall strength of the CAAD7 frame, but the dent resitance is a little suspect in my opinion. This is true for all thin walled Al frames and to a lesser extent, thin walled steel frames.

Let the bike fall against a tree or pole and you will likely get a top tube dent. For all other purposes, the frame should be more than stout enough.

Ed
re: Softer ride: caad7 vs carbon seat stays? Is Caad7 fragile?russw19
Mar 10, 2003 10:25 PM
This is common with bars hitting the top tube. The first time it happens, expect a dent. It should only be an aesthetic dent, not a structural one, but it's still an ugly dent your top tube.
I had the same thing happen to my lowly little Cad3, and have seen the same dent in every series of Cannondales since.

Russ
re: Softer ride: caad7 vs carbon seat stays? Is Caad7 fragile?Leroy
Mar 10, 2003 10:40 PM
My earlier generation (caad5) cannondale surprised me, too. When I first rode it I couldn't believe how smooth it was. I would not hesitate to take it on a century. I like having a bike that is made out of the same material everywhere.
Ride better steel than what you've tested. nmSpunout
Mar 11, 2003 4:20 AM
I think you mean ride better "designed" steel, no? nmMel Erickson
Mar 11, 2003 6:59 AM
re: Softer ride: caad7 vs carbon seat stays? Is Caad7 fragile?nate_
Mar 11, 2003 6:24 AM
no aluminum bike, especially road, is built to last all that long. if this is a quality you value, you want steel. know that in reality steel frames are not really less efficient, nor are they usually much heavier. i would suggest looking at different steel bikes more seriously and seeing if the life is still being sucked out of you. also note that you shouldn't be expected to spend this much money based on quick parking lot rides.
And what, pray tell, do you haveMel Erickson
Mar 11, 2003 7:04 AM
that backs up this statement? Test results? Long term comparisons? Even anecdotal evidence? This type of "urban legend" statement can't really be supported without some type of proof. Can you offer us any?
re: pray tellcyclopathic
Mar 11, 2003 8:48 AM
I know a steel frame which has 120,000mi+ on it. Do you know any Al with comparable mileage?
I know a manMel Erickson
Mar 11, 2003 1:30 PM
who's 103. Do you know anyone born after 1950 of a comparable age?
re: I know a mancyclopathic
Mar 11, 2003 3:16 PM
frame is ~12 years old get a grip. Also MB1 and Miss M ride steel I am sure they have a frame with 50,000mi+ and a few years younger.
It's obvious you missed my pointMel Erickson
Mar 11, 2003 4:14 PM
Steel has been around for 100 years, aluminum a much shorter time. We really don't know from anecdotal evidence (of which yours proves nothing, in fact all anecdotal evidence proves nothing) what the life expectancy of aluminum is. We really don't know what the life expectancy of steel is. There is so much more to life expectancy of a frame than the material. See the link to some testing done by a German magazine. Most failures are mechanical due to stress risers or materials of disimilar stiffness (thick bottom bracket/thin chain stays). These are design/engineering/construction problems, not material problems per se. A good quality aluminum frame, like a Cannondale, should last a good long time. Long enough for any of us to grow tired of it and move on to a new one. I've got an '86 Cannondale bone shaker that I still use on the wind trainer (excellent use for a stiff frame). I have no idea how many miles it has on it but it's go a few. Still going strong. How's that for anecdotal evidence?
no I didn't butcyclopathic
Mar 11, 2003 8:23 PM
you missed mine.

we're prejudice there's no way either your or me will change opinion: discussion is pointless. Your original post clearly indicates it. I am just being cooperative waving red flag in front of you.

With respect to anecdotal evidence the testing done by Germ 'zine purely qualifies as such.

I cannot imagine applying 1,200n (270lbs) and then 1,300n (~300lbs) for another 100,000, using one randomly selected frame of unspecified size being remotely realistic. 100,000 cycles in top gear is roughly ~500mi and only top sprinters can sustain power in test for a few seconds. Using unreasonably high load will skew results toward stiffer frames. Yawn
Yada, yada, yadaMel Erickson
Mar 11, 2003 8:32 PM
You can lead a horse to water but you can't make him drink. Sure there are many limitations to the testing but at least it has a methodology and a basis in objectivity. Hard to say that about "I know of a steel bike with 125,000 miles". Curious, though, that the steel bikes performed the worst. I'll take that test over an urgan myth anyday.
And what, pray tell, do you havemmaggi
Mar 11, 2003 9:03 AM
Mel,

I think we're all aware that in the long run AL tubes are more prone to failure at the stress points than STEEL tubes. I have read reports stating this, but I do not have them at my disposal.

But many other factors come into play such as riding style, number of miles, road conditions, etc. This all plays a part for any frame of any material and the life of it.

I'm sure there are many AL frames that have logged 20k miles. But many have not. I have 4k on mine and still counting. If I get 10k miles, I'll be more than happy. I'm pretty confident that I will.
Some proof.....divve
Mar 11, 2003 9:47 AM
....seems that I have to whip out these links every once a while...:)

http://www.efbe.de/etour109.htm
http://www.efbe.de/etou1098.htm
http://www.efbe.de/erenn.htm
Thank youMel Erickson
Mar 11, 2003 1:29 PM
I was about to post a link to the same article which resides on Sheldon Browns website. He has archived most of Damon Rinards musings from his now defunct website. Although not absolutely definitive this testing is about the only objective info we have. Everything else is conjecture, urban myth and anecdotal.
And what, pray tell, do you haveupandcomer
Mar 11, 2003 5:43 PM
Proof:

Steel has an endurance limit. Meaning if the stress is low enough, the material can be stressed infinitely many times and it will not fail. Aluminum has no such endurance limit meaning that all Aluminum frames will break eventually even if this may be many years (or not so many depending on the amount of stress) down the road.
True, butMel Erickson
Mar 11, 2003 6:54 PM
With proper design/construction that limit is so high as to be practically (as in, well beyond anyones ability to tolerate the same bike for that long) infinite. See the German test referenced earlier. The steel frames did the poorest, not due to the material failing because of it's inherent properties, but because of design/construction faults. Modern aluminum frames, Cannondales for example, are designed to withstand a practical lifetime of use.
re: Softer ride: caad7 vs carbon seat stays? Is Caad7 fragile?snowman3
Mar 11, 2003 9:07 AM
Hopefully I can take 'em for a longer ride. The LBS let me ride down the street and around the block, so it wasn't purely parking lot.

I had tried a Lemond Buenos Aires and Zurich, is there better steel in the $1500-$2000 range? The Lemond ride was so smooth I almost fell asleep and they handled beautifully. My only complaint was that I had to put effort into every pedal stroke.... as if I was always riding slightly uphill. When I tried the AL bikes it felt as if I was almost coasting. I'll try both bikes with the same wheel set. Of course, good steel + good wheels = good amount of money.
re: Test rides...russw19
Mar 11, 2003 2:35 PM
Snowman, call the shop ahead of time and ask them if you can take the bike out for an hour. If your local shop is worth a damn and they want your 2 grand, they will let you. Offer to leave a driver's license and a credit card. If they don't care for the idea, ask them if they will rent you a bike for the day to test ride, and if you buy a bike from them if they will credit that to the purchase. Show them you mean to buy a bike, and they will work with you. But also explain you are not stupid and will NOT drop 2 grand on a bike after a 5 minute test ride. You really need to test ride a bike when you are fully warmed up and it's even better if your muscles are slightly fatigued. That way if a frame is too stiff and is going to beat you up after an hour, you can tell. But you can't tell Jack from riding a bike around the block. That's how shops treat 13 year old joy riders, not serious customers. If your shop doesn't want to let you ride the bike long enough to see if it fits you right, ask them what their return policy is. If they have none, and won't let you ride long enough to really test ride the bike, go somewhere else. There has to be another shop that you would rather spend your money at anyways.

However, I have never come across a shop in my life that has been that unreasonable if you explain to them that you are serious about buying and are not willing to part with that kind of money without a thorough test ride first. But the unfortunate aspect is that bike shop's get ripped off now and again and people steal bikes on test rides... so you may have to convince them you are for real first.

Russ
Other steel bikes in the $1500-$2000 rangetnbiker
Mar 11, 2003 3:21 PM
Check out the specialized FOCO bikes. yes, they are using high end steel tubes.

The comp is $1700 msrp and the elite is $1400