Bike Forums - Why not aluminum frames?

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Why not aluminum frames?

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

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.

aluminum is a fine frame material. it has its own strengths and weaknesses that dont suit some.

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.

They're noisy, stiffer, more delicate

but I love mine

Because we are all sheep and repeat everything we read as gospel.

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

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.

Quote:

Originally Posted by cc700 (Post 9073411)

frame material matters VERY little.

Sheldon:

Quote:

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
Saddle choice. See my Article on Saddles.
Frame geometry. Generally, frames with longer chain stays, and less vertical seat-tube and head-tube angles 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

Quote:

Originally Posted by dervish (Post 9073510)

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.

Quote:

Originally Posted by cc700

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.

Quote:

Originally Posted by rudes333 (Post 9073376)

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.;)

Quote:

Originally Posted by rudes333 (Post 9073376)

I happen to like my aluminum frame quite a bit.

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.

Quote:

Originally Posted by jhaber (Post 9073471)

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.

Quote:

Originally Posted by carleton (Post 9074144)

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.

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.

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.

Quote:

Originally Posted by Jabba Degrassi (Post 9074165)

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.

Quote:

Originally Posted by TwoShort (Post 9074193)

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?

Quote:

Originally Posted by jhaber (Post 9074201)

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.

Quote:

Originally Posted by carleton (Post 9074224)

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

Quote:

Originally Posted by carleton (Post 9074244)

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!

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.

Quote:

Originally Posted by clink83 (Post 9074268)

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!