Comfy aluminum frames?

[alan lavine]

Haven’t ridden aluminum in many years, it always beat me up. But technology improves and maybe there’s something new I don’t know about. So is “comfy aluminum “ an oxymoron or can it really exist? Interested in your thoughts and experiences,

Alan nyc

[Mathias Steiner]

Hi Alan,

I have a habit of taking in a stray bike every year, usually in the fall, and then make it my baby for the following season. Living in Michigan, that's a sound approach with plenty of time for the rehabilitation. My tastes run to the old and cheap, but maybe I can offer some perspective for your question.

In 2021, that bike was a 1997 Cannondale R200 Criterium bike. Look up "harsh aluminum" on wikipedia, and there'll be a picture of it. Quick handling, maximum tire size 28 mm [GP5000, 26 mm actual] and there was a 16th of an inch gap at the seat tube. I liked riding it, and with a Technomic stem I found it comfortable, but if you rode over a coin in the road, you could tell whether it was heads or tails. Last year's bike was, a 1987 Cannondale ST600 that I got as a frame set from a friend on bikeforums. Fantastic riding sport touring bike, no vices, quick-enough handling but not nervous, and with 32 mm GP5000s, 30 mm actual, a fine ride. It has a classic steel fork with a proper crown, I'm guessing that helps. It's not harsh at all, and dirt-road capable so long as there's no deep sand or gravel. This year I'm riding a 1981 Motobécane Grand Touring, light-weight Vitus tubing, 27x1-1/4 Paselas, also 30 mm actual width, and it rides just like the ST, only it looks better doing it. The ST is at best 1 mph faster on my timed rides, but those Contis are low-rolling-resistance tires. I don't believe I'm wasting energy anywhere else on my bicycles.

Finally, my Forever Bike is a '95 Cannondale T400 -- so I'm partial to 'dales, what of it?  -- that I bought new. It's shod with 700x35c Paselas measuring 36 mm and I run them in the 40s. That bike is not harsh at all the way it is set up, and it's my go-to ride for mixed roads. When the things being pushed around by a frame are the rubber tires below and my ample hind quarters above, there is no difference in "give" between a triangle made from steel vs. aluminum tubes. I will say that any kind of rattle, like from the pannier hooks on the racki, sounds nasty on a big-tube aluminum frame. Maybe that's where the myth of the "harsh riding" aluminum frames comes from.

"Comfy aluminum" really does exist. Look for a frame with a geometry that suits your riding and with room for the kind of tire you like. Problem solved. Aluminum will never look as korrekt as steel does, but that wasn't what you had asked. Please let us know what you find in your travels... my foray into different bikes has mostly taught me what I'd read before.. it's hard to build a bad bicycle.

cheers -mathias

[Ryan]

What Mathias says is right about older Cannondales with cro-mo forks. I also had a T600 Cannondale that I bought in 1988 for about $650-700 - red 18-speed with half-step gearing with a Biopace(remember those?) Deore crank...bike was a mix of 600 and Deore. It was a fine touring bike that also rode well unloaded; quick enough and actually a lot more fun and chill than the Rossin with Campy SR that was my go-fast...which I hardly rode after I got that Cannondale. The Rossin I sold on without a tinge of regret. Loaded touring, centuries , fast club rides...it was a great bike...until I fell in love with a 93 X0-1...which over 50 miles in my fitter youth, I didn't like as much as the Cannondale, if I'm honest. 

[alan lavine]

Interesting. I had a T1000 touring bike years ago, and even then I found it too rigid. As I age this issue takes front and center, I'm like the princess and the pea. I agree that the first step is always fat, supple tires. For me, that eliminates any frame that can't take anything bigger than 28's.

As always, YMMV.

[Nick Payne]

As I said in another thread (https://groups.google.com/g/rbw-owners-bunch/c/tAas6urcOwg/m/KW63fr0LCQAJ), modern aluminium frames can be quite comfortable. Last week I did back to back rides on successive days over the same chipseal roads on that Al bike and on my Riv custom. I can't say that the Riv felt any more comfortable or better handling. The Al frame was running Conti GP Urbans and the Riv Rene Herse Bon Jon Pass, both nominally 35mm tyres.

Nick Payne

[Will M]

Alan, Jan Heine's 2021 book, All Road Bicycle Revolution, has some good reading on this topic ("characteristics of a great frame can be obtained from all materials"; p. 174) that aligns with Sheldon Brown's writing from 20 years ago ("the reality is that you can make a good bike frame out of any of these metals, with any desired riding qualities, by selecting appropriate tubing diameters, wall thicknesses and frame geometry").  They both argue that the "feel" of a frame is influenced more by frame design than by the material itself. 

This doesn't answer your question.  :-)

I'm not sure I have an answer.  All I know is that my aluminum Yuba Sweet Curry cargo bike is the stiffest thing on the planet (to give 300-lb cargo capacity; look at all the aluminum trusses!).  

And that I agree with Matthias: my "forever bike" is also a C'dale adventure touring bike (this T1000; the aluminum CAAD2 touring frame) that turns 25 in December.  I had posted previously about how I am slowly turning it into an Atlantis, having drunk too much Kool-Aid in Walnut Creek.  But I must say that the T1000 rides better than any RBW bike that I've owned.  Blasphemy, but there it is.  Something about its chromoly fork's geometry gives it magical handling.  If only it had the Atlantis's clearances.  I am waiting for the aluminum to fail so I can get in line for the next Atlantis batch. :-)

Will M

NYC

[alan lavine]

Appreciate your thoughts, everyone.

[Jason Fuller]

I was hoping I could track down what I had read not long ago on some very interesting thin-wall aluminum bikes that were produced in, I believe, the 1980s. With aluminum lugged construction if I'm recalling correctly. Apparently they rode wonderfully and are nothing like the big-box aluminum bikes we're used to today. 

Steel is three times as stiff as aluminum, all else equal. So you'd think aluminum frames would be less stiff!  Except, because its also lower strength and doesn't have the fatigue resistance of steel, tubing is made larger and thicker which more than offsets this. The aluminum frames can still be lighter because the yield strength to weight ratio is better with aluminum, and by using larger diameter tubing, stresses can be kept low enough to not have fatigue issues (for the expected frame lifespan ... eventually, their time will come, which isn't necessarily the case for steel).  The reason you don't see aluminum frames with a nice flex to them like well-made steel frames, is because if aluminum is allowed to flex to that extent it will fatigue quickly and end up failing. Under a certain level of stress, steel won't fatigue, but aluminum still will, no matter the stress. So with aluminum you've got to keep the stresses low enough the fatigue life is longer than anyone's likely to ride the bike. 

Aluminum is really popular these days because you can thicken up that frame quite a bit, protecting the manufacturer from warranty claims for dented or cracked frames, without it getting super heavy. The lack of rust is a big plus in the casual cyclist's eyes, and the ease at which the tubing can be formed to all kinds of shapes (via hydroforming, among other processes) makes designing elaborate cargo bikes and the like a lot easier.  The rough ride tends to be solved by wider tires these days; suspension being the next line of defence. I reckon it's more attractive for the manufacturer to sell you suspension, which they can up-charge for... and also, as little sense as it makes to all of us, steel is seen as 'outdated' compared to aluminum for bicycle frames. It's dead wrong but .. well, so are a lot of the general public's notions about things. 

[Joe Bernard]

Jason, 

You're probably thinking of Alan frames, which were also sold under a couple other bike brands. 

https://www.ebay.com/itm/284647880399?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=-_TAxF-oSJe&sssrc=4429486&ssuid=mIm2WqOOS_O&var=&widget_ver=artemis&media=COPY

Bridgestone also imported something similar for a couple years, the Radac. 

[Nick Payne]

On Saturday, 12 August 2023 at 4:20:00 pm UTC+10 Jason Fuller wrote:

I was hoping I could track down what I had read not long ago on some very interesting thin-wall aluminum bikes that were produced in, I believe, the 1980s. With aluminum lugged construction if I'm recalling correctly. Apparently they rode wonderfully and are nothing like the big-box aluminum bikes we're used to today.

There's a good article on these frames here: https://on-the-drops.blogspot.com/2016/12/the-peugeot-px-10du-vitus-979.html.

Back in the late 1980s I had an SR Litage, which was similar to the Vitus in that it used normal diameter aluminium tubes with lugs bonded internally to the tubes. With the aluminium fork, it was an extremely comfortable bike to ride - I can remember using it for an Audax 1000 fitted with really skinny 19mm tyres, so that I could shoehorn mudguards onto a bike not designed for them, and finding that it was perfectly comfortable over that distance. Unfortunately the bike was stolen out of my house in the early 90s, and I never acquired another aluminium frame until the Mason that I bought recently.

Nick Payne