Singlespeed & Fixed Gear - Why not aluminum frames?

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




Pages : [1] 2

View Full Version : Why not aluminum frames?


rudes333
06-09-09, 07:44 PM
I have been doing a lot of looking around and reading on the singlespeed & fixed gear threads for about the last month. Why does it seem like you guys don't like aluminum frames for fixed/single speed bikes?

Thanks


PedallingATX
06-09-09, 07:46 PM
b/c it's better.

EDIT: For one, it's more expensive (generally). Two, it has fatter tubes which a lot of fixed gear riders don't like the look of. Three, it's "fragile." Four, it's uncomfortable b/c it doesn't absorb shock the way steel does. Five, There just aren't that many good aluminum FG bikes out there. Sure, there are some, but not as many as steel. Six, steel is reel. man.

adriano
06-09-09, 07:48 PM
aluminum is a fine frame material. it has its own strengths and weaknesses that dont suit some.


cc700
06-09-09, 07:51 PM
frame material matters VERY little.

frame construction matters VERY much.

a cheap aluminum frame is going to be overbuilt by any company who knows what they're doing. should be fine.

iansmash
06-09-09, 07:59 PM
They're noisy, stiffer, more delicate



but I love mine

jhaber
06-09-09, 08:00 PM
Because we are all sheep and repeat everything we read as gospel.

Check Sheldon Brown: http://www.sheldonbrown.com/frame-materials.html

wearyourtruth
06-09-09, 08:00 PM
i think it's mostly 2 points (both of which have been touched on)

1) most people here use their fixed gears for city riding. the issue is not that steel is better than alum for fixed gears, it's that steel is better than alum for city riding. good steel is a much more forgiving ride over bumps and curbs and potholes. while alum is stiffer, most people are not TRULY mashing their way through town like they would be in a cat 2 race or on the velodrome, and prefer the give of steel over the lack of give in alum.

2) i think a lot of people just prefer the look of simple round tubing, which isn't really an option on alum fixed gear frames.

dervish
06-09-09, 08:06 PM
frame material matters VERY little.



no

jhaber
06-09-09, 08:07 PM
Sheldon:


Stiffness and ride quality

Frame stiffness (or the lack of it) doesn't have as much effect on ride quality as many people would lead you to believe. Let's look at it from a couple of different directions: Torsional/lateral stiffness

This is mainly related to the stresses generated by the forces you create from pedaling. Any frame will flex around the bottom bracket a bit in response to pedaling loads. This flex can be felt, and many riders assume that it is consuming (wasting) pedaling effort. Actually, that's not the case, because the metals used in bicycle frames are very efficient springs, and the energy gets returned at the end of the power stroke, so little or nothing is actually lost. While there is no actual loss of efficiency from a "flexy" frame, most cyclists find the sensation unpleasant, and prefer a frame that is fairly stiff in the drive-train area. This is more of a concern for larger, heavier riders, and for those who make a habit of standing up to pedal. Another area where lateral stiffness can be an issue particularly to the touring cyclist is the rear triangle, when there's a touring load on the rear rack. An frame that is too flexy in this area will feel "whippy" and may be prone to dangerous oscillations at high speeds. Most of this flex is usually in the luggage rack itself, but there can be enough flex in the seat stays to aggravate this condition.
Vertical stiffness

(Since this article deals with frames, the issue at hand is road shock transmitted from the rear tire to the saddle. Ride qualities experienced at the handlebars are to some extent determined by the fork, as well as geometry, and flex in other bolt-on parts, but are un-related to the choice of frame material.) Much of the commonplace B.S. that is talked about different frame materials relates to imagined differences in vertical stiffness. It will be said that one frame has a comfy ride and absorbs road shocks, while another is alleged to be harsh and make you feel every crack in the pavement. Virtually all of these "differences" are either the imaginary result of the placebo effect, or are caused by something other than the frame material choice.
Bumps are transmitted from the rear tire patch, through the tire, the wheel, the seatstays, the seatpost, the saddle frame, and the saddle top. All these parts deflect to a greater or lesser extent when you hit a bump, but not to an equal extent.
The greatest degree of flex is in the tire, probably the second greatest is the saddle itself. If you have a lot of seatpost sticking out of a small frame, there's noticeable flex in the seatpost. The shock absorbent qualities of good quality wheels are negligible...and now we get to the seat stays. The seat stays (the only part of this system that is actually part of the frame) are loaded in pure, in-line compression. In this direction, they are so stiff, even the lightest and thinnest ones, that they can contribute nothing worth mentioning to shock absorbency.
The only place that frame flex can be reasonably supposed to contribute anything at all to "suspension" is that, if you have a long exposed seatpost that doesn't run too deep into the seat tube, the bottom end of the seatpost may cause the top of the seat tube to bow very slightly. Even this compliance is only a fraction of the flex of the exposed length of the seatpost.
The frame feature that does have some effect on road shock at the rump is the design of the rear triangle. This is one of the reasons that touring bikes tend to have long chainstays--it puts the rider forward of the rear wheel. Short chainstays give a harsh ride for the same reason that you bounce more in the back of a bus than in the middle...if you're right on top of the wheel, all of the jolt goes straight up.
Where Comfort Comes From

If you're looking for a comfortable ride, it is a mistake to focus on the particular material used to build the frame. There are differences in comfort among different bikes, but they are mainly caused by:

Tire choice. Wider, softer tires make more difference to ride comfort than anything to do with the frame. Unfortunately, many newer sport bikes are poorly designed when it comes to tire clearance. For the last decade or more there has been a fad to build frames with very tight tire clearance, although there is no performance advantage whatsoever to such a design. Such bikes cannot accept anything but super skinny tires, and, as a result, there's no way they can ever be really comfortable. See my Article on Tires (http://www.sheldonbrown.com/tires.html)
Saddle choice. See my Article on Saddles (http://www.sheldonbrown.com/saddles.html).
Frame geometry. Generally, frames with longer chain stays (http://www.sheldonbrown.com/gloss_ch.html#chainstay), and less vertical seat-tube and head-tube angles (http://www.sheldonbrown.com/gloss_an-z.html#angle) are more comfortable. This doesn't make them any slower, but may reduce maneuverability (also known as twitchiness.)
Rider positioning. See my Article on Pain and Cycling (http://www.sheldonbrown.com/pain.html)

cc700
06-09-09, 08:17 PM
no

compared to how they're made and how the bike is built up, yes.

a slack geo aluminum bike with a suspension seat post and soft saddle is going to be way less buzzy than a hardened steel frame.

if the butting isn't sized well it will be heavy. basically, the construction matters way more than the material. steel isn't necessarily heavy and aluminum isn't necessarily light, nor are they necessarily comfy or anything else. it's all in the construction.

dougland89
06-09-09, 08:23 PM
steel is real.
aluminum on the street is hell.
they're more fragile.
they dent easily.
they're fat.

Ken Cox
06-09-09, 09:39 PM
a slack geo aluminum bike with a suspension seat post and soft saddle is going to be way less buzzy than a hardened steel frame.

No one makes a "hardened steel frame."

Some bicycles steels feature air-hardening in the vicinity of the Heat Affected Zones of TIG-welded frames, in accordance with the intent of the people who design steel tubes for bicycles; otherwise, steel frames remain remarkably flexible and "springy" because the majority of the frame's steel, outside the Heat Affected Zones, remains flexible and "springy."

Slack geometry, suspension features and padding characterize aluminum bikes because of the harshness of an aluminum frame and fork.

Additionally, aluminum fatigues quickly with road vibration.

One sees 20 year-old steel road and track frames but will not see 20 year-old aluminum road and track frames.

Given the suspension systems typical of modern mountain bikes, we might see 20 year-old mountain bike frames.

mihlbach
06-09-09, 09:53 PM
Why does it seem like you guys don't like aluminum frames for fixed/single speed bikes?


People who don't like aluminum are idiots*.
https://www.bianchiusa.com/typo3temp/6d8a10ef3a.jpg


*Except for K. Cox...he's not an idiot, he just overthinkings everything.;)

rrooster
06-09-09, 09:55 PM
I have been doing a lot of looking around and reading on the singlespeed & fixed gear threads for about the last month. Why does it seem like you guys don't like aluminum frames for fixed/single speed bikes?

Thanks

I happen to like my aluminum frame quite a bit.

vegipowrd
06-09-09, 10:02 PM
There is also the purely pragmatic issue that Al frames are harder to convert. This is partly an accident of bike history. Al frames became less expensive at the same time dropouts became almost totally vertical.
Track frames are mostly made by more independent makers. Steel is more forgiving to build up because the welds are easier.
Thick steel frames are heavy, but still ride well. Thick Al frames aren't much lighter, ride like a rock, cost more and look like crap. Great steel and great Al each have advantages.

carleton
06-09-09, 10:08 PM
Because we are all sheep and repeat everything we read as gospel.

Check Sheldon Brown: http://www.sheldonbrown.com/frame-materials.html

+ 1

Yeah, you ever notice how fixie hipsters know about gear that apparently no other cycling scene knows about? Somehow they adopt 20+ year old technology and it's somehow better than modern stuff because somehow old sh*t performs better with age.

I mean if triathletes knew about Aerospokes then they would totally abandon their Zipps. If roadies knew about Brooks saddles they would totally abandon their Fiziks. If track racers knew about MKS Sylvans they would totally abandon their Speedplays.

For some reason fixie culture has grossly blurred the lines between fashion and function. The fixie scene is the *******ization of Track Racing and the Classic and Vintage scenes.


So, if you care about fashion then do god knows what. If you care about function, buy a modern track bike or fixed gear...that will be Aluminum or Carbon Fiber.

Jabba Degrassi
06-09-09, 10:14 PM
So, if you care about fashion then do god knows what. If you care about function, buy a modern track bike or fixed gear...that will be Aluminum or Carbon Fiber.

Plenty of modern frames are steel. Steel frames and modern components are not mutually exclusive.

TwoShort
06-09-09, 10:22 PM
Some people think steel gives a noticeably smoother ride than aluminum. They are probably well meaning, but are obviously wrong. The Sheldon article excerpted above lays out rather convincingly, and better than I could. Worth reading in full.

For city riding, steel may be preferable because of the result if you whack in to something and put a big dent in your bike: If it was steel, you have a beat up bike. If it was aluminum, you don't have a bike.

jhaber
06-09-09, 10:26 PM
Reason steel is cool:

1. It is easier to find custom fitted frames in steel.
2. Thin tubes look nice.
3. You could fix a dented/broken steel frame although probably less than 1 percent of 1 percent of frames ever get fixed (just a guess).
5. Thin walled alu frames dent too easy (so does thin steel though).
6. Carbon frames will explode and you will die.
7. Ti is too expensive (so is nice steel).
8. You get to fit in with the ssfg forum boys.
9. Steel is real.
10. You didn't realize I skipped number 4.

carleton
06-09-09, 10:31 PM
Plenty of modern frames are steel. Steel frames and modern components are not mutually exclusive.

No they are not. They are just retro designs for entry level bikes. Very few if any modern bikes use steel. Steel is more rare than carbon fiber in your local bike shop.

Yes, the new Specialized Langster is steel. But, that's a retro bike. Just like the Bianchi Pista. NJS? R-E-T-R-O.

Of course, then when Trek, a company that has put more money into R&D than most in the game, introduces the T1 the BF crowd takes a dump on it. "Ewwww...a compact design." That same compact design won some dude a bunch of races in France.

carleton
06-09-09, 10:39 PM
Some people think steel gives a noticeably smoother ride than aluminum. They are probably well meaning, but are obviously wrong. The Sheldon article excerpted above lays out rather convincingly, and better than I could. Worth reading in full.

For city riding, steel may be preferable because of the result if you whack in to something and put a big dent in your bike: If it was steel, you have a beat up bike. If it was aluminum, you don't have a bike.

Um, there are plenty of aluminum bikes with dents that didn't explode on contact. Yes, steel is easier to repair, but at what cost? How many people have totaled or almost totaled a bike? So, I'm going to carry the extra wight of a steel bike around 100% of the time on the .001% chance that I may wreck it and it still be repairable?


Reason steel is cool:

1. It is easier to find custom fitted frames in steel.
2. Thin tubes look nice.
3. You could fix a dented/broken steel frame although probably less than 1 percent of 1 percent of frames ever get fixed (just a guess).
5. Thin walled alu frames dent too easy (so does thin steel though).
6. Carbon frames will explode and you will die.
7. Ti is too expensive (so is nice steel).
8. You get to fit in with the ssfg forum boys.
9. Steel is real.
10. You didn't realize I skipped number 4.

1. That's because steel is easier for people to use to make bikes in a small shop.
2. Not really, but that's subjective.
3. Correct. There are plenty of dented aluminum frames that ride just fine, too.
5. You just negated your own point.
6. Yeah, some dude exploded last week. Big flames everywhere. But, I'm sure you know how it works.
7. True and true.
8. Hahaha
9. Yeah, and Aluminum is imaginary. Carbon Fiber divided by zero.
10. I did.

Jabba Degrassi
06-09-09, 10:43 PM
No they are not. They are just retro designs for entry level bikes. Very few if any modern bikes use steel. Steel is more rare than carbon fiber in your local bike shop.

Yes, the new Specialized Langster is steel. But, that's a retro bike. Just like the Bianchi Pista. NJS? R-E-T-R-O.

Of course, then when Trek, a company that has put more money into R&D than most in the game, introduces the T1 the BF crowd takes a dump on it. "Ewwww...a compact design." That same compact design won some dude a bunch of races in France.

Retro design? Perhaps. But unless it was built 10 years ago, it's still a modern frame.

jhaber
06-09-09, 10:43 PM
10. I did.

Damn I just made up the rest to get to # 10 (or 9 to be real). Damn you bike forum... you win again.

Also Keo of Keo-spin fame says that riding an alu bike is like riding in a square while steel is like riding in a circle or something like that. I am pretty sure he is legit!

clink83
06-09-09, 10:43 PM
If you rode two bikes with the same diameter tubes and same geometry, and the only diffrence was frame material, you wouldn't be able to tell a diffrence in ride quality.
As for "steel being a thing of the past" thats BS. The whole bike industry is all about selling you **** racers use that you don't need. Steel is outdated like a 39t small ring on a normal double is useful.

krusty
06-09-09, 10:57 PM
As for "steel being a thing of the past" thats BS. The whole bike industry is all about selling you **** racers use that you don't need.

Dude! You post stuff in some threads that has people ready to kick you to the curb, then you post something like this. Dead on!

dougland89
06-09-09, 10:59 PM
Reason steel is cool:

1. It is easier to find custom fitted frames in steel.
2. Thin tubes look nice.
3. You could fix a dented/broken steel frame although probably less than 1 percent of 1 percent of frames ever get fixed (just a guess).
5. Thin walled alu frames dent too easy (so does thin steel though).
6. Carbon frames will explode and you will die.
7. Ti is too expensive (so is nice steel).
8. You get to fit in with the ssfg forum boys.
9. Steel is real.
10. You didn't realize I skipped number 4.

this. and i LOL'ed

carleton
06-09-09, 11:02 PM
Finally, I don't want to hear the argument about steel being repairable. Why? Because NOBODY has ever cashed in that chip.

"But I can if I need to."

Yeah...but you won't.

It's reasonable to believe that anybody buying a $300 Kilo TT or a $600 Pista IS NOT going to spring the cash for someone to professionally repair a dent in that bike. So shut it.

carleton
06-09-09, 11:08 PM
As for "steel being a thing of the past" thats BS. The whole bike industry is all about selling you **** racers use that you don't need.

"Steel in real" is what custom steel bike manufacturers tell you so you will buy their sh*t. It's all a game.

Other things the steel crew will say to scare you into buying steel:

"Steel flexes and comes back. Aluminum flexes and breaks. You wouldn't want that to happen at 30MPH"

"You're a big dude. You'd crush an aluminum bike. You should ride steel."

"Aluminum is sooooooo harsh on anything over a mile ride. Steel is like riding in a Cadillac...if I rode in cars...which I don't."



Any of that sound familiar?

dougland89
06-09-09, 11:11 PM
Finally, I don't want to hear the argument about steel being repairable. Why? Because NOBODY has ever cashed in that chip.

"But I can if I need to."

Yeah...but you won't.

It's reasonable to believe that anybody buying a $300 Kilo TT or a $600 Pista IS NOT going to spring the cash for someone to professionally repair a dent in that bike. So shut it.

yeah but the fact that you can ride a dented steel frame with confidence unlike a dented aluminum frame

Ivandarken
06-09-09, 11:27 PM
All this talk about things that don't really matter. Go to bed.

Wake up tomorrow and ride whatever you have. Unless you are a champion cyclist, a good quality bike is just as good as a better quality bike. The academic exercise is fine, but the material of your bike really just doesn't matter... as long as it is steel.:lol:

carleton
06-09-09, 11:28 PM
All this talk about things that don't really matter. Go to bed.

Wake up tomorrow and ride whatever you have. Unless you are a champion cyclist, a good quality bike is just as good as a better quality bike. The academic exercise is fine, but the material of your bike really just doesn't matter... as long as it is steel.:lol:

Hahahaha :D

kiMBos
06-09-09, 11:36 PM
All I know is there are many MTB bikes made of aluminum ridden hard. Few in steel. I wonder why.

Steel will bend before aluminum tube will crack. Steel is not as stiff as aluminum. Actually steel will flex a bit when riding hard.

But I like steel for it's good looks and ride quality.

Yan
06-10-09, 12:38 AM
Thin steel tubing looks better than fat aluminum tubing.

CharneK
06-10-09, 01:03 AM
I wonder what a magnesium frame/fork would feel like...? I'm also surprised I haven't heard anything regarding nanotubes yet. Longboarders are already using it.

Though if you want to be super hip and cool, you build a frame out of pure bronze or wicker :twitchy:

jhaber
06-10-09, 01:17 AM
I prefer wood frames or for you purists out there I might recommend bamboo.

the_don
06-10-09, 01:19 AM
Easton already use them in their CNT (carbon nanotube) composite components.
http://www.eastonbike.com/PRODUCTS/TECHNOLOGY/tech_cnt.html

CharneK
06-10-09, 01:22 AM
Easton already use them in their CNT (carbon nanotube) composite components.
http://www.eastonbike.com/PRODUCTS/TECHNOLOGY/tech_cnt.html

Ah, I knew someone had to be using it. Magnesium though? or is this just to crazy expensive or something. I could be grossly mistaken but I thought I remembered it being something like twice as light and 4 times stronger than AL. Anyone?

queerpunk
06-10-09, 06:09 AM
Finally, I don't want to hear the argument about steel being repairable. Why? Because NOBODY has ever cashed in that chip.

"But I can if I need to."

Yeah...but you won't.

It's reasonable to believe that anybody buying a $300 Kilo TT or a $600 Pista IS NOT going to spring the cash for someone to professionally repair a dent in that bike. So shut it.

I've bent my IRO's fork back into shape. A buddy of mine got a steel road bike and ruined a fork in a crash, got the frame bent back into shape. A guy I know nearly ruined a de rosa thanks to a pothole in the wrong place... bent it back into shape.

Anyway, this thread is amusing because it's full of half-truths followed by no-you're-wrongs.

tcs
06-10-09, 06:24 AM
Before Klein, aluminum bikes (ALAN) were known for noodlely handling and cushy rides. This was all before you were born.


Magnesium though?

http://www.paketabike.com/

And Kirk Precision, of course.

Reynolds (http://www.reynoldstechnology.biz/magnesium.html) can fix you up with a magnesium tube set.

tcs

SUPER STEVE
06-10-09, 06:26 AM
I ride my aluminum frame 20+ miles all of the time. Now my seat is the reason I don't ride longer. It doesn't get along with my taint.

etothepii
06-10-09, 06:58 AM
I like my old Technium frame. Holding up well so far :)

queerpunk
06-10-09, 07:05 AM
Before Klein, aluminum bikes (ALAN) were known for noodlely handling and cushy rides. This was all before you were born.

That was very different technology. Frames were being built like they were steel frames from the time - thin tubes, thick tube walls. Once people realized that alu could be made thinner, things got relevant - because the walls could be made thinner, the tubes could be made larger, and it would still be lighter.

aidy
06-10-09, 07:38 AM
There's one area where steel isn't 'Redundant, duhh!!' and that's touring. Outside of that it matters little what your bike is made of.

norskagent
06-10-09, 07:44 AM
No one makes a "hardened steel frame."


Additionally, aluminum fatigues quickly with road vibration.

One sees 20 year-old steel road and track frames but will not see 20 year-old aluminum road and track frames.



Won't see them because they are out there failing, or it hasn't been 20 years yet? I've seen both aluminum and steel frames fail from fatique, stress, or whatever. Should we sell our aluminum frames now before they reach their half-life?

devilshaircut
06-10-09, 07:50 AM
For the general posting population of this board, I think steel is favored for the following reasons:

- It is very durable.
- It is very (very) cheap.
- Availability ... many options for steel frames.
- Conversions are popular and popular conversion frames are often steel.
- The quality of a steel ride is (generally) more comfortable on the streets.
- Historically, it is steel frames that are are associated with craft and artistry.
- Steel has a popular look.

I think most people here eschew aluminum because it is less comfortable (mostly due to the construction methods involved but also the material itself), less durable, rarer, etc.

That having been said though, aluminum frames are more than capable of handling the streets wonderfully. Just because steel is more durable than aluminum doesn't mean that aluminum isn't durable. It is. Personally, I have 2 aluminum bikes and they work fine for the streets. I won't be riding either of them for polo though because they are more expensive than my steel bikes. :)

queerpunk
06-10-09, 08:01 AM
I wouldn't like my TK2 for all-around uses for a few reasons. It's a bike built for racing, and that means that the wheelbase is very, very short, and that it's pretty stiff. The ride is jarring and that's no fun on a 25mi rt commute on crappy streets (my COG is so high and the wheelbase so short that when I go over rough pavement I feel as though my wheels are barely on the ground). I don't like locking it up because the wrong toss against a pole and I've got a nice dent in my thin downtube.

Interestingly enough, in the road scene, alu has the reputation for rugged durability. But that's a very different use for the bike.

As people have said, material is far from the be all and end all about how a bike feels. Geometry and shape of the tubing come in to play a whole bunch, as well as quality of tubing. Throw a carbon fork and seatpost into the equation to change it up further.

devilshaircut
06-10-09, 08:13 AM
I've noticed that the shape of tubing makes the most marked difference. My friend has an aluminum bike with large diameter, round tubing, very similar to the aluminum used on my tandem. The ride of these two bikes is much less jarring than my aero aluminum frame. I think the carbon fork helps mitigate this though.

elTwitcho
06-10-09, 08:44 AM
I can't understand what drives some members to get hostile over someone's choice in frame material, that's just childish.


Anyway, the reason you see a lot of steel is in part because fixed riders are generally utility riders, not racers. Track racers or road racers don't use steel as much as this forum, but they also don't commute on their bikes, don't lock them up, and don't find themselves in situations that leave their bike as banged up as a rider who uses their bike for transportation. To say that the needs of a person commuting in the city (the majority of ssfg riders I believe) are the same as a person who is racing on a closed course is misguided.

Not surprisingly, steel remains popular among the touring crowd

devilshaircut
06-10-09, 08:59 AM
I can't understand what drives some members to get hostile over someone's choice in frame material, that's just childish.

Pretty sure half the bike paraphernalia choices people make around here cause people to get hostile. Hell, there is a blazing argument taking place right now over whether or not it is okay to steal possibly abandoned bikes. People with argue over anything and it's pretty clear that people who ride steel love their steel bikes. Even BSNYC devotes entire articles to ripping on things like bike lights.

I think people enjoy the arguments or at least get something informational out of them, perhaps a new perspective. I dunno.

The Octopus
06-10-09, 08:59 AM
My aluminum IRO Jamie Roy frame handled just fine on the 254-mile ride I took it on a week and a half ago. Not at all what that bike was designed for, but it performed just fine: it didn't blow up from fatigue, it didn't cause my junk to go numb, and it wasn't any noisier than a carbon road bike with gears.