OK, I just got back from the lbs. He is the second lbs to tell me that both CF and AL have a lifespan of 5-6 years. NEITHER asked me how many miles I plan on riding. I see the thread running that 4800 miles is nothing for a bike, but before I drop $$ on a new bike, I wanted to know what's up with this "lifespan" thing. I understand all bets are off from a crash or damage. I'm just talking normal riding.

The bikes I'm looking at have limited lifetime warranties, but would like to know what to expect before jumping in.

And PLEASE, is it possible not digress into a "plastic sucks"/ "aluminum sucks"/"steel is real" thread. I've read a lot of those threads.

Thanks.

I'm selling my Aluminum Klein on ebay. I'm the original owner and bought it in 98. Still rides great, I rode it just last week.

Then he is the second lbs to spew numbers out of his ass. Lifetime in this context is a pretty meaningless concept.

Calm down. Think about your question real hard...take a deep breath...do more research...then think about the question one more time...repeat until logic comes into play.

There's still cannondales from the 90s and even 80s that are still on the road today. He just wants to sell you a new bike in 5 years.

ok Joe since you're local to me, please tell us (or at least me via PM) which shops are blowing so much smoke. I know plenty of people who still have and ride carbon and aluminum frames from as far back as the 80's. I know even more people who frequently fly on commercial airplanes made of the same aluminum that were built as long ago as the 1970's.

I know that the sales people at shops frequently know little more about bikes than the price tag and brand, but that kind of comment is pathetic.

I would think it depends on the construction of the frame among other things, doesn't Cannondale have a lifetime warranty on all of their frames?

Aluminum will last just as long as any steel bike. the only advantage steel has over aluminum in terms of lifespan, is that it can be repaired much easier and it is less prone to damage in crashes.

carbon fiber im not so sure about. i dont no anyone who uses a carbon fiber bike regularly (in terms of commuting or day to day riding) so i couldnt speculate. i would bet if you just use a carbon fiber sporadically for races and other more specialized riding, they could last for 10+ years

I've got a '00 Trek 5200 with approximately 30K miles on the frame. I've raced it, crashed it, commuted on it, worn through all sorts of components, and the damned thing won't die.

PM sent.

I'll be the first to admit that my current Rock Hopper doesn't have as many miles as it should (yes, I know, it's a MTB, but right after I bought it, I realized it was a mistake and it hasn't seen the dirt since), but it's from the mid 90's. I am the type that researches things to death, then buys the best I can afford at the time and keeps it for a very long time. I can not afford "upgrade'itis".

Thanks for the insights. I'm going to go talk to Bicycle Johns in Acton on Saturday. I'll be interested to hear his take on it...and see how hard he laughs at me!

If this were true, no one would pay several thousand dollars for a bike only be told to replace it in 60 months. It's just absurd for anyone to even come up with this kind of statement.

I had an aluminum bike from the 1970s a year or two ago. A girl gave it to me, and I found it a new home. It's about 30 years beyond the end of its life, if that bike shop is right, but the lady who owns it now is getting plenty of use out of it.

I have a carbon road bike and alu cross bike. The CX one I bought used; I have no idea what it's history is, but it definitely had some wear. I've since put about 3,700 miles on it. It's still in great shape, although I need a new battery for its computer.

Lots of components will eventually die, given enough use. For example, you might need to replace the chain every 1,000 to 1,500 miles, and the tires get a bit more than double.

Take a look around the shop and see what kind of bikes they are selling. I bet both those shops you went to don't stock much in CF or AL bikes. I've had Vitus 979, Cannondale and Nishiki alloy frames I bought used at 4-5 years old and had no problems with using them for another 3-4 years of racing. I also had a Peugeot Comete that I tore apart, but that was more manufacturing and design issues rather than materials. I've got a '91 Specialized Allez Epic with over 50k-miles on it and no problems whatsoever. There's some chips in the gel-coat, but the CF's just fine.

Get the bike that you want, from the material you want, that fits you well and is comfortable and ignore everything the shop muppets are pushing. Heck, the percentage of high-school dropouts that are working in shops have increased tremendously since I've worked in one.

I have no issues with "wear and tear" and maintenance. And I had a hard time believing the "lifespan" theory, however, IF there were some truth to it, better to know up front than later!

I think both CF and Alu will last longer than you want to keep the bike. I ride with people riding CF bikes from 1999, and still looks in very, very good condition. Alu bikes...heck, I'm sure those last longer than my lifetime.

Nothing real to add from me, but I have an aluminum mountain bike from 89 or 90 with tens (if not hundreds) of thousands of miles on it, the only original part left is the frame.

There was nothing wrong with my 7 year old TCR Composite when it was stolen last month. And I'm "heavy" at 185.

I don't buy this at all. Maybe some of the lower quality brands might only last five or six years, but my CF bike is already six years old and I haven't had any problems with it. I know of people still riding CF bikes from the late 80s and they ride just fine. I suppose if you put over 100,000 miles on an aluminum frame it might it have a problem, but if you put that many miles on a bike I would say you got your money's worth.

You can BITE ME! Heavy at 185! If that's the case, I'm a featherweight 232!

Al does not have a fatigue limit (the absence of a fatigue limit means its getting one step closer to death with every stress cycle), and it does corrode. I would not bank on a very light aluminum frame put to heavy use to last forever. I have seen older C'Dales that pretty much were ridden to death, and they have thicker tubing than current uberlight AL frames.

That said I think you can likely expect well more than 5-6 years out of the lightest aluminum frame, even if you're riding 10,000 miles annually. Assuming you don't dent it in the wrong spot.

For CF frames, don't crash them, or let it get abraided, and the lifespan ought to be longer than CF.

I had a friend put over 50,000 miles on a carbon 1996 lemond before it developed a crack in the bb shell about 2 years ago.

I was 232 when I bought my used 2001 Calfee in 2006. I replaced it with a used 2004 Calfee in 2008. The 2001 didn't fit me. I am down to 210
but still not a light weight.

At 232 lbs, a carbon bike can easily handle your weight.

It is repairable! I would fix it before I would replace it.

As long as you don't wreck it, they should outlast you. Not sure why any LBS would say that, is all that they sell either steel or titanium? CF is more fragile then even AL but it should still last way longer the 5 years as long as it's not damaged.

Some of the earlier CF frames built in the early 90's did have issues with the bonding of the AL bottom bracket to the CF BB shell and those would seperate and crack the BB shell in the process. But they have better bonding today. But I personally am a bit concerned with CF frames coming out of China, but that's just me.

Hey, if those shops were right it would be a GOOD thing depending on the right brand.

I have a Trek and their CF frames are guaranteed for life. That would mean a new free bike every 5-6 years! That would be awesome.