Do aluminum frames eventually crack?
 

I've read (somewhere) that they will. I've got a 13 yr old cheap hybrid that has seen a lot of abuse on tours but mostly riding over curbs, etc...around town.

I'd like to go on another trip soon but would hate for that to happen.
I only weigh 155 lbs with 25 lbs of gear so maybe I have nothing to worry about.

All rims are aluminum anyway. Seems like this myth doesn't pass the laugh test.

I've got the original rims and rode this cheap bike across the country already.
It's probably just me dreaming about a new bike and I'm looking for an excuse.

I have had both steel and aluminum frames fail. Aluminum frames are prone to failure with no warning, steel usually will give you a bit of notice by creaking. Aluminum has a different fatigue cycle than steel, typically less. With your weight you probably haven't stressed you bike as much as somone that is bigger and stronger. Take off and at the worst you will have to buy a new bike along the way.

Aaron :)

I remember when I was buying my touring bike, there was a lot -- and I mean a lot -- written about steel vs. aluminum frames. One of the things frequently mentioned about aluminum frames was that they tend to fail without warning, as wahoonc, said. I always wondered how frequently that happens in the real world. In my limited, anecdotal, completely un-scientific experience, not very often (though I'd be very interested to hear if anyone has any real statistics on this). Don't worry about it and if it cracks, it cracks.

That being said, I'm all for you getting a new bike. You can never be too careful :P

have been riding a Trek 1100 for 24 yrs now,..so far so good

I have a 1987 Trek 8000 Aluminum that has 100,000+ miles on it -
Including brutal, loaded-down touring on dirt & gravel.
Plus I'm a big kid - 190 lbs.

Maybe I've been lucky. Maybe Trek still made their bikes in the U.S. back then.
But I would never trade in the solid feel of an aluminum frame for spaghetti touring - - ever.
YMMV

If your dreaming about a steel bike I'd get one :) Steel is real.

OTOH: Your bike is probably good to go. Nothing wrong with aluminum.

Unlike steel, aluminum doesn't have a well-definied fatigue limit. That means that aluminum parts will eventually fail, even if they aren't abused. With that said, a well-designed frame could conceivably last for tens of years and tens of thousands of miles.

boomhauer, I ride aluminum and have frames dating from '86. They'll last a lifetime, but there is one thing in particular to look for and that is a crack in the tubing. Normally this will occur where a tube is dented by accident and, far less often, where two tubes join. On the other hand a steel tube with a crack shouldn't be dismissed either.

When aluminum started to become popular there were basically two types of tubing used, 6XXX and 7XXX. Some early 7XXX frames were considered brittle, but while that seems to have been remedied pretty quickly it didn't help aluminum's reputation. Few, if any of the aluminum touring, mountain bike and hybrid frames are made from the flyweight tubing found on the period road racing frames (many of the early aluminum road racing frames aren't either), if that soothes the soul any. ;)

Brad

PS I feel that most sudden frame failures, other than sudden impact, had a 'failure in progress' that wasn't caught early.

I've got a 2010 Cannondale T1. Give me another twenty years and I'll tell you how it goes. Al

my '06 diamondback wildwood got cracks in both chainstays after 3 years of rough use.
no apparent damage, no dents, no accidents. no way to fix, so it's now been reincarnated
as a truing stand.

my '89 mercian vincitore got a small groove cut in one chainstay by a too wide tire.
ten minutes (and $20) got a nice patch job by a backyard framebuilder in rural virginia.

If you want a new bike go for it, but for me at least, worry that an aluminum frame might crack wouldn't be the reason.

If I had your bike, and had the ability, time and money to go on a long trip, a cracked frame would be the last thing on my mind.

Enjoy the trip, and the new bike it sounds like you're going to get!

All those aluminum rims ready to implode

Single anecdote interruption.

Cannot be a simple Yes/No..

Thing is, how is the aluminum flexed? less flexing cycles are required to crack aluminum than steel..

the reason that aluminum frames have evolved to be stiff, is survivability ..

that is why the tubes have gotten fatter, to make them stronger, but weigh no more..

My anecdote:

Past owner of 2 AlAn frames, Light racing frames, with screwed and glued joints,
both developed 'lug' cracks ..

each replaced by Steel frame bikes..


newer buy a Koga Miyata WTR, 7005 Aluminum frame
It has a lot of overkill added on it for strength,
and has been heat-treated in a couple stages after welding..

My Cannondale is currently over 20 years older than yours with well over 100,000 miles on it and hasn't had any problems. The steel bikes I've had that cracked didn't have nearly that much mileage - and one of the failures was very sudden and resulted in injuries.

I've heard the biggest difference wasnt durability, but carrying capacity and frame flex while touring. True?

You gain stiffness by either adding to the tube Outside diameter shape at the welded joins,
or Wall thicknes , triangulation..

Moulton went with a bridge truss like grid of triangles .. Tout terrain C'dale , Koga,
and many Diamond frame bikes went with OD increase, and tube shaping, often the Hydroforming ,
bigger at head tube, and BB as that is where the stresses are higher ..

steel tubes long ago went with increasing the wall thickness at the ends , Butting.

by the way Airplanes have carefiul logs of hours of service , then they are grounded .

one stress they have that bikes don't, is cabin pressurization..

I have heard that Cannondale Aluminum Touring Bikes are notorious for cracking spontaneously and catastrophically and because of that FACT I would be more than happy to save you that grief and potential injury and so please allow me to purchase your 55-56 cm bike at a greatly reduced cost. Thank you.

Almost all the name brand aluminum bikes are fabricated in Taiwan by I think it is three factories. No matter if they have a North American, European or Asian company logo. To my way of thinking what you pay extra for getting a name brand is the external quality assurance of the branding company that is putting their logo on the frame. I tour on a US designed, Taiwan made, Shimano equipped, Bianchi logoed very lightweight triple butted aluminum cyclocross bike.

I tour extensively over USFS roads and even single track. I have jack-knifed the bike with an over loaded trailer and once watched it tumble over a twenty foot high cliff. I don't dismiss "the aluminum will fail" myths and before every tour I carefully inspect all the welds. But with 60,000+ kilometers the concern has lost some of its edge. What's worse, by some accounts, is my bike has carbon forks.

Beside if the frame fails you will have an interesting story to tell or perhaps your grieving kin will have a company to sue.:rolleyes:

Western Flyer, It maybe now true that most bikes, of any material, are made in the Pacific Rim area, but at one time Klein, Trek and Cannondale were Made in the USA.

Altbark, Per my favorite LBS, as soon as Cannondale announced that no more T bikes were going to be manufactured there was a rush to purchase them. My LBS thinks that he found the last one of the size he needed for a customer at a warehouse...no other dealers had one to trade.

Brad

PS I think that the only aluminum touring frame still in production is available from Nashbar, which it seems like a good frame by those that own one.

Koga Miyata in the NL a TW subsiderary, make the 7005 alloy frames in their touring /trekking bikes .
then the Frames are shipped to Rotterdam, for assembly in NL..
but they only have 2 dealers in the US..

Around DC , in MD. and one in Santa, Barbara Cal.

.. though their signature program lets you menu shop; pick components and frames ,

have it built up, in the NL company , and shipped to a dealer Outside the US,

and meet it over there . Panniers in hand, and ride away..

several are quite close to AMS Shiphol Airport , for example.


sort of like Volvo used to do , fly and drive , then they shipped the car across the Atlantic
like they would have anyhow, to your dealer ..

Eventually, any frame will crack. The question of whether you or your decendents will be riding it at the time is harder to answer.

I have a 2011 Specialized Allez I bought on closeout in mid-March last year. It has just crossed the 20,000 mile mark and it's still going strong. The only trouble has a 'burr' on the inside of the rim that appeared while on a 2600 miles bike trip last summer. I didn't find the problem that kept giving me a darn flat tire every 40 miles until after I got home and really started to inspect the entire wheel. A little flake of metal from the rim that was stuck to the rim tape and causing me all kinds of misery.

I've had exactly the opposite experience. Both steel frames...along with pedal shafts and axles and spokes... went "PING!" and were broken. No warning whatsoever.

The aluminum frame...and rims and crank... creaked and groaned and I eventually found the crack. But it didn't fail without warning nor did it fail catastrophically.

Thanks for the correction. I almost took German delivery on a 1984 VW GTI, but I bettered that with a brand new daughter!

Brad