Aluminum frame life

tri4fun said:

I have a Cannondale 2.8 road frame that has gone through various periods of abuse. Never crashed though. It is at least 6 years old. My neighbor used to work for Shimano and said that the frame is too old. Then while riding it and climbing I've noticed it may be flexing (maybe not , can't figure if that is just in my head or the extra 25 LBS I now carry).
What is a real realistic frame life for the infamous rigid Cannondale?

Your neighbor is full of sheot,and you need to put down the crack pipe and let the grey matter heal.An aluminum frame will eventually fail.The designers know that and design in several 'lifetimes' of use. It won't go soft or mushy ,it will just eventually break. Ditch the extra pizza and beer and it will last alot longer.

boudreaux said:

Your neighbor is full of sheot,and you need to put down the crack pipe and let the grey matter heal.An aluminum frame will eventually fail.The designers know that and design in several 'lifetimes' of use. It won't go soft or mushy ,it will just eventually break. Ditch the extra pizza and beer and it will last alot longer.

I looked into the thread because I wanted to find out a similar thing. I have an Eddy Merckx Team Sc that is 3 years old. I rode it about 6000 kms each year. The first year it felt really tight and the second as well. Now going into the 4th year I noticed flex that wasn`t there. I keep going "is it my impression?" but I don`t know.
I am wondering if it is the frame or the wheels that is causing this, but the bike just does not feel stiff and "tight" as it used to. It still handles great going downhill and is still comfortable but.... I am a bit heavy (94kgs) but I actually have lost weight since buying it (from 99kgs) so it`s not like I added weight which causes it to flex.
It would be interesting to hear people`s point of view on this. I also seem to remember that Principia included an offer with their bikes to the effect that after 5 or so years they would retreat it (heating was involved? I don`t remember) to regain the original stiffness. Does that mean that aluminum does become flexy with usage maybe?
I don`t know, but if anyone has substantiated views on this please share them.

George K. said:

I looked into the thread because I wanted to find out a similar thing. I have an Eddy Merckx Team Sc that is 3 years old. I rode it about 6000 kms each year. The first year it felt really tight and the second as well. Now going into the 4th year I noticed flex that wasn`t there. I keep going "is it my impression?" but I don`t know.
I am wondering if it is the frame or the wheels that is causing this, but the bike just does not feel stiff and "tight" as it used to. It still handles great going downhill and is still comfortable but.... I am a bit heavy (94kgs) but I actually have lost weight since buying it (from 99kgs) so it`s not like I added weight which causes it to flex.
It would be interesting to hear people`s point of view on this. I also seem to remember that Principia included an offer with their bikes to the effect that after 5 or so years they would retreat it (heating was involved? I don`t remember) to regain the original stiffness. Does that mean that aluminum does become flexy with usage maybe?
I don`t know, but if anyone has substantiated views on this please share them.

I'm not familiar with how Aluminum fails, but the idea that it stays as stiff as the day it was bought and then one days just abruptly fails without warning seems illogical to me.

tri4fun said:

I have a Cannondale 2.8 road frame that has gone through various periods of abuse. Never crashed though. It is at least 6 years old. My neighbor used to work for Shimano and said that the frame is too old. Then while riding it and climbing I've noticed it may be flexing (maybe not , can't figure if that is just in my head or the extra 25 LBS I now carry).
What is a real realistic frame life for the infamous rigid Cannondale?

First of all, your bike is probably a lot older than 6 years. The 2.8 was made around 1990. In addition to being extremely stiff, the early Cannondale frames are also very durable. I have a 1991 with the 3.0 frame that's been through a lot of miles and some major crashes without any cracks. As for the flex, you should periodically inspect around the joints between the chain stays and bb shell for cracks. If you've gained 25 pounds, the flex you're noticing is probably in the rear wheel or bb spindle.

tri4fun said:

I have a Cannondale 2.8 road frame that has gone through various periods of abuse. Never crashed though. It is at least 6 years old. My neighbor used to work for Shimano and said that the frame is too old. Then while riding it and climbing I've noticed it may be flexing (maybe not , can't figure if that is just in my head or the extra 25 LBS I now carry).
What is a real realistic frame life for the infamous rigid Cannondale?

As long as you don't have any cracks the stiffness of the frame won't be affected by age and re-heat treating the frame won't make any difference.

Stiffness would be affected by the development of cracks though. Check very carefully around the areas of transition from the weld bead to the tubing.

George K, I have a Merckx as well.

The problem you have is with the carbon stays, not the aluminium. I can assure you that 6k even at your weight will not stress the aluminium that much.

I had a mate with an old look frame, full carbon, and he could bend it. He couldn't bend it much, but he could definately bend it. But then he was huge and it had '000's of kms on it.

As for the cannondale, I used to have a 2.8 and I'm pretty sure the frame came with a life time warranty. I take it they don't do that any more.

tri4fun said:

I have a Cannondale 2.8 road frame that has gone through various periods of abuse. Never crashed though. It is at least 6 years old. My neighbor used to work for Shimano and said that the frame is too old. Then while riding it and climbing I've noticed it may be flexing (maybe not , can't figure if that is just in my head or the extra 25 LBS I now carry).
What is a real realistic frame life for the infamous rigid Cannondale?

an extra 25lbs is a lot, so it may increase the flex, but your spokes may also need retensioning.

All you've gotta do with alu is keep checking for cracks when you clean it, especially under and around the bottom bracket, the down tube, and the rear drop-outs. Small cracks often first appear as "suspicious" paint movement.

As long as you regularly inspect it, there's no need to worry.

531Aussie said:

an extra 25lbs is a lot, so it may increase the flex, but your spokes may also need retensioning.

Contrary to popular belief, tightening your spokes will not affect the stiffness of the wheel. It will however destroy your rims. Unless the bottom spokes are going slack, don't mess with the tension.

http://www.sheldonbrown.com/rinard/wheel/

AussieRob said:

As for the cannondale, I used to have a 2.8 and I'm pretty sure the frame came with a life time warranty. I take it they don't do that any more.

They still do,but it doesn't and never did apply to fatigue failure.

Thanks for the replies. I checked the frame and the integrity is still there. The wheels (Mavic Heliums) are probably the culprit with flexing. Just bought some strong (but heavier) wheels to help the lateral stiffness.

Thanks again

Another concern with older aluminum frames is spidering. When you get a dent in the frame unlike other frame materials, aluminum will spider and eventually significantly weaken the frame's integrity.

I would like to chime in on the way a bike seems to, "loosen up," over time. We are forgetting to factor out the improvement of the motor. Any new bike feels stronger because we are not pushing as hard as we do after we have ridden the bike for a few years. If you regularly ride a bike you become used to it and stronger riding it. The increase in flex is evidence that we are pushing harder, not that that bike became more flexible.

As far as failing is concerned, for those who wonder, a frame doesn't suddenly break catastrophically. It starts with a little crack that grows each time the bike is ridden. This is why you inspect your frame meticulously. You can ride a lot of miles with a crack growing under the chainstay near the bottom bracket without noticing it until the tube suddenly breaks. This was not a sudden failure. The crack started out tiny and gradually grew in an exponential manner. Of course there are also times when a small crack is the place where a tube breaks when a large shock is applied to the frame such as in a crash or a hard drop.

Do not forget that bikes are machines and like all machines can last a very long time if maintained properly or fall to pieces if beat to [censored]. Such is life.

I've had a few aluminiums over the years. I looked this up years ago before I bought my first, but aparently they're good for about 10 years under day to day use, but drop to about 3-5 years during competition use. Start to worry when it begins creaking.

Bill.
🙂

shannons dad said:

I've had a few aluminiums over the years. I looked this up years ago before I bought my first, but aparently they're good for about 10 years under day to day use, but drop to about 3-5 years during competition use. Start to worry when it begins creaking.

Bill.
🙂

Make sure the creaking ain't your knees.

shannons dad said:

I've had a few aluminiums over the years. I looked this up years ago before I bought my first, but aparently they're good for about 10 years under day to day use, but drop to about 3-5 years during competition use. Start to worry when it begins creaking.

Bill.
🙂

Thanks for all the replies. Regarding my Merckx now that you mentioned it, I do hear a creaking noise that I can`t explain when riding it but I thought it came from the wheels or the seatpost. I will definitely have a closer look and probably take it to a good bike shop to have a close look. Thanks for the tips all.

The creaking is most likely because you need to grease the seat post and or bottom bracket. 90% of all creaking complaints stems from one or both of these areas needing a simple greasing. It's impossible to locate where a creak is coming from while you're riding, so start with the seat post since that's so much easier to grease and see if that does the trick. If the creak is still there do the bb.

50mph said:

Another concern with older aluminum frames is spidering. When you get a dent in the frame unlike other frame materials, aluminum will spider and eventually significantly weaken the frame's integrity.

I have an '87 Cannondale frame that has been crashed a few times and seen a couple different riders. I sold it to a friend back in '89 for some quick cash, he used it for about 10 years exclusively and then as a back up for about 5 years before giving it back to me. I recently built it up with some spare parts to use as a spare bike and was surprised to find it was still stiff as hell. In fact I do some sprint intervals in the same spot all the time, and the fastest speed I have ever hit was on the old Cannondale (I could have had good legs that day, but the difference is more than 2 mph's). It is a very harsh ride that now rattles my old bones, so I have stripped it down and have it hanging up on the wall. It's a real beauty that came with a custom paint job and is stamped with the initals of the welder and the painter. I know any metal can break over time, but I would never tag a certain metal as having a set lifespan. I seriously doubt I could crack that old C-dale and I'm a big guy.

shannons dad said:

I've had a few aluminiums over the years. I looked this up years ago before I bought my first, but aparently they're good for about 10 years under day to day use, but drop to about 3-5 years during competition use. Start to worry when it begins creaking.

Bill.
🙂

I'm a 200lb sprinter with a 1 year old trek 1000, and it's creaking during group ride sprints.

Oh [censored]. :eek:

I got some frame checking to do.

mezzinator said:

I'm a 200lb sprinter with a 1 year old trek 1000, and it's creaking during group ride sprints.

Oh [censored]. :eek:

I got some frame checking to do.

99% of the time, the creaking is coming from a loose crank bolt or bottom bracket. While cause for concern, don't panick about your frame until you've ruled everything else out.