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Thoughts on Aluminum CX frames?(16 posts)

Thoughts on Aluminum CX frames?tns1972
Sep 20, 2002 11:53 AM
I like aluminum for it is responsive fell and quick acceleration, but I don't see alot of CX frames built from this stuff. Will the ride be too harsh?
re: Thoughts on Aluminum CX frames?lookin for help
Sep 20, 2002 12:00 PM
I went steel for 3 main reasons:
I am not going to race it.

I think the ride is better when relying on the frame to absorb the shock. I remember riding my presuspension aluminum mtn bike on rough roads and that was never too much fun.

Longevity - I wanted this bike to last me a long time and I think I have a much better chance of that with steel than aluminum. I will leave the aluminum for my hardtail mtb.
re: Thoughts on Aluminum CX frames?tns1972
Sep 20, 2002 12:14 PM
I love my Alu Hardtail Mtb too, but won't aluminum out live steel?
Aluminum out live steel, not likely (nm)Wheelz
Sep 20, 2002 12:26 PM
Aluminumatpjunkie
Sep 20, 2002 1:12 PM
have 2 cross bikes both Aluminum. Most small boutique mfr's still build steel and they are great, much better on longer rides. Steel does tend to last longer , barring corrosion, which can be common in the wet and gunk of cx. Aluminum is lighter, stiffer and not as damped as steel. On long rides it can knock your fillings loose unless it's high grade Aluminum (7000 series) or Aluminum Composite (ie..Specialized m4, m5) which produces a much smoother ride than it's cheaper counterparts (still not as smooth as steel) I'm a steel nut on the road but my rides are usually 3-6 hours and steel helps in this application. For cx (especially racing) the duration is usually less than an hour so it isn't as much of an issue. This is why most top 'race' bikes (Empella, Ridley, Colnago) are all Aluminum or Aluminum Composite. Racers tend to choose weight and Stiffness over comfort. Figure what your application is going to be and then choose based on your needs and riding style. If you are on a budget choose steel as cheap Aluminum can be harsh.
Aluminum is NOT stiffer than steel.flyweight
Sep 23, 2002 9:07 AM
Aluminum is NOT stiffer than steel. That is a fact of science. If aluminum were actually stiffer than steel then please explain why track bikes use steel handlebars or why spokes are steel?

What makes many aluminum bikes ride so stiff isn't the aluminum (or even the grade of aluminum as you imply) but rather the diameter of the tubing. This is simple physics though it's something many "experts" in the bike industry seem oblivious to.

Probably the plushest cross bike ever made - the Alan - was made from aluminum (and not the higher grade aluminum) What made the bike so comfortable was that instead or relying on oversized/thinwall tubing it relied on relatively normal sized/thicker tubing.
Aluminum is NOT stiffer than steel.atpjunkie
Sep 23, 2002 1:38 PM
we've already had this discussion. yes I know as a metal steel is stiffer, it's why BMX and downhill stuff is made out of it. But by Aluminums thinner wall / thicker tube diameter usage in frame building Aluminum Bikes (not the metal) in general ride stiffer. Yes a thin tubed Aluminum Bike will be plush but in reality very few exist. We've been down this road before, and we all agreed in "Theory" Aluminum is less stiff than steel, but in "Practice" Aluminum Bikes (we are discussing bikes not metalurgy) ride stiffer than steel. I know it can be done but no one does it so why discuss a thin tubed Aluminum bike. Mfr's use All kinds of composite Aluminums, butting and / or swaging to reduce this stiffness (caused by tube diameter). There had to be some reason for not using small/ thicker Aluminum tubes, I just don't know it.
psatpjunkie
Sep 23, 2002 1:45 PM
my S-Works uses a smaller tube Aluminum (Metal Matrix) and it is quite plush. My Ridley has a coffin shaped downtube, I'll let ya know how it is on completion.
Aluminum is NOT stiffer than steel.flyweight
Sep 24, 2002 7:44 AM
Actually there have been and still are aluminum bikes with narrower diameters and thicker tubes. The Alan and Vitus aluminum bikes have just such tubes and the Alan has been ridden to victory in more major 'cross races than any other model of frame. Sean Kelly rode a Vitus aluminum frame to more wins in one year than most pros chalk up in an entire career.

The reason oversized aluminum tubing has become the norm, especially with MTBs, has absolutely nothing to do with performance and everything to do with economics. Larger diameter tubes are easier for the robots in Taiwan to weld. Simple as that. Economics are also why threadless headsets and v-brakes caught on so quickly. As far as the manufacturers were concerned it had nothing to do with performance and everything to do with cost.
Aluminum is NOT stiffer than steel.atpjunkie
Sep 24, 2002 11:40 AM
there is a design reason as well. Oversize tubing because of it's larger diameter can be made thinner and due to larger contact patch for the weld, stronger at the joints than smaller diameter as stress loads are distributed over a greater area. So for the same size bike a thin wall / large tube bike is lighter and stiffer than a thick wall / thin tube bike. They are trying to maximize their strength to weight issues with less regard to ride. This is especially true at the start of the big tube revolution as most were quite the filling rattlers (Cannondale Pre CAAD3 for example). Personally I think thin tube bikes are far more attractive. I'm sure there is a lot of validity to the robot argument as well.
Aluminum is NOT stiffer than steel.flyweight
Sep 25, 2002 10:30 AM
The robot argument came directly from a product manager and they should know.

I also prefer thinner tubes even though two of my bikes are oversized aluminum.
Aluminum is NOT stiffer than steel.atpjunkie
Sep 25, 2002 7:59 PM
oh I believe it. Ya know the threadless thing may be cheaper but it knocks off some serious weight as well. I took over a quarter .lb off my roadbike switching from threaded to threadless. I know part of it is from threaded steel steerer to threadless alloy which again puts us in the steel/aluminum thing. As for road bikes I still ride stell, to me they feel nicer and the thin tubes look better. Glad my S-Works CX has thinnish tubes.
For cx I like Steel.Wheelz
Sep 20, 2002 12:24 PM
I went with steel, because steel tends to last longer than other frame metals over time. I am not a light guy, and so I punish bikes. I have already broken several frames, both steel and aluminum.

I do race, but I also ride my cx bike as a mtn bike. I like the positive feel of no suspension, especially climbing. My bike is more comfortable than similar aluminum bikes I've ridden, while being reasonably light (19 lbs).

Steel tends to be less expensive and can be repaired if it is damaged. The frame builder that made my frame is local, and I have had him do work on the frame, once. I broke a drop out and had it replaced.

Expanding on the last point there are a number of steel frame builders that make great custom cross bikes. Here are just a few: Rock Lobster, Sycip, Independent Fabrication, Steelman, and Richey. I personally ride a Rock Lobster and I am very happy.

wheelz
I'm going aluminumshawniemc
Sep 20, 2002 1:12 PM
After test riding several cx bikes I've decided to go with the Bianchi Axis (aluminum). I road some steel bikes (the Steelman, Jamis) and they just didn't give me that loving feeling like the Bianchi or the Kona Jake (also aluminum) did. Sure, they were a little bouncier on the single track, but that's worth it too me.
re: Thoughts on Aluminum CX frames?Velocipedio
Sep 21, 2002 4:22 PM
It's funny how the metal wars never really flare up in cyclocross. Roadies [and I'm one, BTW] can go on for hours about the relative benefits of steel vs. Aluminum vs. something else. 'Crossers seem to be of the opinion of "weel, they're different, so it depends what works for you..."

You do actually see a fair number of aluminum 'cross bikes. Most of the pros' bikes are aluminum and most of the big-brand bikes, like the Kona Jake and Bianchi Axis are, too.

I love my Jake. It's a rocket on climbs and it does accelerate in a rush... having said that, I also love my steel road bike. It may be counterintuitive, but I think I actually prefer aluminum off-road. As one poster observed, it might be bouncier, particularly on grass and turf, but I find the low-pressure tires moderate the harshness, and I find the stiffness helps grinding out of holes...
re: Thoughts on Aluminum CX frames?flyweight
Sep 23, 2002 9:13 AM
It all depends on how the tubing is used. Most oversized aluminum tubes are going to be stiffer than or more conventional sized steel tube. On the other hand aluminum is a more flexible material.

Most 'cross bikes have adopted a relatively modest diameter that tries to strike a balance between stiffness and comfort. Each will be a bit different. Buying a bike based solely on the tubing is pretty foolish. It's much better to simply ride as many bikes as possible and then later worry about what it's made out of.