Recumbent - Aluminum vs Steel frames

Some say Aluminum frames are too stiff, no flex. I am considering a Giro 20TT; 4 1/2 lb lighter, upgraded components and disc brakes, vs steel Giro. I will try one, but am interested in opinions.
Any comments?
Mark

I have a Bacchetta Agio. It's aluminum. I usually prefer steel, and I don't care too much about excess weight. However, mine is a LWB, so it's not too stiff.

The Giro, being a SWB, will be stiffer. Take both aluminum and steel for a ride, and see what you think.

Also, I have discs on my Agio... discs are overrated. Can you get your LBS to build a steel Giro with better components?

I have a Bacchetta Agio. It's aluminum. I usually prefer steel, and I don't care too much about excess weight. However, mine is a LWB, so it's not too stiff.

The Giro, being a SWB, will be stiffer. Take both aluminum and steel for a ride, and see what you think.

Also, I have discs on my Agio... discs are overrated. Can you get your LBS to build a steel Giro with better components?

Looks like the brakes on the Agio are relatively low-price tektro disks. I wouldn't dismiss disks on that basis. The tektro caliper brakes that came on my RANS F5 were among the worst brakes I've ever used, but having previous experience w/ Campy dual-pivots, I knew the problem was those particular brakes, not dual-pivots in general. Sure enough, switching to Shimano 105's fixed it. I'd be willing to bet that Avid BB7's or the like would change your opinion of disks. Or maybe not.

SP

Looks like the brakes on the Agio are relatively low-price tektro disks. I wouldn't dismiss disks on that basis. The tektro caliper brakes that came on my RANS F5 were among the worst brakes I've ever used, but having previous experience w/ Campy dual-pivots, I knew the problem was those particular brakes, not dual-pivots in general. Sure enough, switching to Shimano 105's fixed it. I'd be willing to bet that Avid BB7's or the like would change your opinion of disks. Or maybe not.

SP

Possibly. I'll admit to not being an expert.

I was just a bit underwhelmed with the stopping power they provide. It's adequate, but not great. They are also noisy.

I currently have an Avid Mtn(BBDB) disc on the back of my BikeE and it works very well. I would guess it is not the lightest disc set up due to Mountain spec.
Mark

The Bacchetta aluminum frames are known for having plenty of flex and a smooth ride. They are not like the Alan frames of years ago.

The Bacchetta aluminum frames are known for having plenty of flex and a smooth ride. They are not like the Alan frames of years ago.

Excellent news!:thumb:

I did get the Giro 20TT yesterday. What a wonderful ride. It is quite a bit rougher than my Bike E w/ suspension, but I think I can live w/ it.:lol:
Mark

Glad to hear you like it. I have been considering a Giro 20TT myself. How does it climb? I am mostly concerned with climbing and stability on the downhills.

The Bacchetta aluminum frames are known for having plenty of flex and a smooth ride. They are not like the Alan frames of years ago.

??? My memory must be playing tricks on me. Seems to me that Alans (and Vituses. or is it "Viti"?), with their small-diameter, bonded tubes, were known for their almost excessively soft ride. I test rode one a couple decades ago, and was very much impressed with the ride comfort.

OTOH, I had a second-generation (pre-CAAD) Cannondale aluminum crit bike for a couple years, and I was on intimate terms with every bump, crack, and irregularity in the pavement within 20 miles of home. Great for those 45 minute races, though...

Also, I'd be a little concerned about an aluminum frame with "plenty of flex". Aluminum is one of those materials that has absolutely no fatigue threshold: if it flexes, it WILL break eventually. Titanium is better in this regard, and steel even better. FWIW.

Scott P
Bend, OR

Glad to hear you like it. I have been considering a Giro 20TT myself. How does it climb? I am mostly concerned with climbing and stability on the downhills.

I have only done one short ride, but downhill was very good and uphill was much better than my Bike E.
I am very pleased.
Mark

Excellent news on the Giro TT. Given my short x-seam (39") I am leery of highracers like the corsa though the corsa 24" does hold quite the attraction. I need to get to Angle Lake and try a few rides.

Excellent news on the Giro TT. Given my short x-seam (39") I am leery of highracers like the corsa though the corsa 24" does hold quite the attraction. I need to get to Angle Lake and try a few rides.

Before you seriously consider a Corsa-24, look into the tire selection for that size. Maybe only having a couple of tire choices doesn't matter to you, but maybe it does.

Before you seriously consider a Corsa-24, look into the tire selection for that size. Maybe only having a couple of tire choices doesn't matter to you, but maybe it does.
The wheel-set/tire selection issue and rear brake difference are the two big concerns I have regarding the Corsa-24. I want to try the Corsa (650c) as well and if my improved recumbent skills can manage the Corsa now, then that will be my decision. Otherwise I will waffle between the Giro-20 TT and the Corsa-24.

I need some time on the bikes before I can make any call. In the end the Giro-20 TT may be the best compromise for my needs. I would customize the offering as well. I have ridden on the euromesh seat and probably would swap out the pad for a ventalist (sic) pad. I prefer bar end shifters and would swap them in. I want the fenders which is a push in the Giro direction but I can also use Race Blades which I like as they are so easy to take on/off and Race Blades work on a Corsa. The gearing on both the Giro and the Corsa is great, I like the range they have on current models, I do find it odd how sheldon browns gear inch calculator doesn't match the Bacchetta spec sheet results. But I did catch an inverted number here and there on their page so I am trusting Sheldon's calculator on the range. I will be swapping tires, I don't think I used stock tires on any bike I have ever bought.

The giro-20 TT looks nice and light, has reasonable components and should be pretty fast. In the end, it will probably be my ride.

... I do find it odd how sheldon browns gear inch calculator doesn't match the Bacchetta spec sheet results.

The spec sheet lists 26x1.25 for the rear tire. I think you'll find that the actual diameter for that size tire is about 24.5". Plugging that diameter into my personal gear inch calculator, I come up with 21.5" to 118", which is pretty close to the advertised specs.

The spec sheet lists 26x1.25 for the rear tire. I think you'll find that the actual diameter for that size tire is about 24.5". Plugging that diameter into my personal gear inch calculator, I come up with 21.5" to 118", which is pretty close to the advertised specs.
Indeed, for the Giro it is pretty close. The Corsa lists 32" to 119" though it is more like 23" to 119". That is the one I think was inverted. I always check Sheldon's calculator as I like to swap tires and wheels

Hi,

I had an Agio and really liked it. But, it was too wide to comfortably carry on the rack behind my Honda Civic. I did like the somewhat bouncy frame and the disks. it looked cool, too.

I bought a trike I really liked (Challenge trike), but still wanted a 2-wheel recumbent. I like RWR in State College, Pa (what a creative town name - only surpassed by College Station, Tx). They had a steel Giro 20 which I bought, but I returned it for an aluminum one. To be honest, there might've been a pound or two difference... but then, I had the shell seat on the steel one, and probably heavier mesh seat on the aluminum one.

Anyway, I do really like the Alum. Giro. But the metal difference is mostly in my mind. I do prefer the rim brakes to disks, but again not by much. It's just easier for me to remove and replace the front wheel for carrying... turned out the bike is short enough I don't bother removing the wheel any more.

I think the Giro is significantly faster and more maneuverable than the Agio. The Agio seemed better for relaxed rides.

But then, for really relaxed rides, I take the trike. I've even pulled off a trail, locked the brakes and snoozed on that trike - it's so comfortable!

Here's a video on YouTube of a trike ride on a Pa. Rails to Trails route.

www.youtube.com/watch?v=-5cw7awQQys

Dan

I am considering the corsa and strada and felt that the strada might be better for long distance rides. Any comments from people with experience with both?

I too was stuck between either the steel or aluminum Giro 20. Because I was going to use it for commuting, I liked the frame flex and recurve seat of the steel Giro, but I also prefered the disc brakes of the aluminum version because I ride a lot in wet weather. Ultimately I choose to go with the steel Giro 20 and upgraded it with disc brakes. So far I'm very happy with the combo but I'm sure anybody would be just as happy with either version of the bike.

bacchetta steel frames are overbuilt, so the aluminum frames are softer

bacchetta steel frames are overbuilt, so the aluminum frames are softer

What? How do you know this?

What? How do you know this?

The weight limits of the steel frames are much higher and the weights of the frames themselves are much much higher and Bacchetta themselves claim the aluminum frames are more flexible.

Steel is actually not inherently more flexible than aluminum, it's just that aluminum frames have a reputation for being stiff because the frames themselves are typically designed to be stiff, but both steel and aluminum Bacchetta frames appear to be designed the same. In other words, while a thin tubed steel bike would be more flexible, that's not how Bacchetta makes their steel bikes.

Having owned both a Strada (steel) and Corsa SS (aluminum), the aluminum framed Corsa transfers the power thru the frame more efficiently, imo. I notice this when I climbing steep hills. The steel framed strada also felt bouncy, especially on long decents. Both bikes run 100-125psi

Having owned both a Strada (steel) and Corsa SS (aluminum), the aluminum framed Corsa transfers the power thru the frame more efficiently, imo. I notice this when I climbing steep hills. The steel framed strada also felt bouncy, especially on long decents. Both bikes run 100-125psi

Yeah, this is what I thought both metal types handled in regards to Bacchetta frames.

I got my Giro 24TT up to 49 mph on the downhill west side of Donner Pass earlier this mo and it was rock solid at that speed(peddle as I might, I could not make 50). I passed several DF bikes:)
Mark

Aluminum bikes are designed to be stiff because, while steel has a very long fatigue cycle as long as you keep it below the fail point, aluminum does not. In aluminum, any bending is forbidden because it will work-harden with each bending cycle until it is so brittle that it snaps. Maybe some newer alloys don't have this issue, but if there are, I'm not aware which they might be.

I personally don't have a problem with stiff recumbent frames. After all, it's not like you have a stick poking up your butt, hammering you every time you hit a bump.

As someone pointed out aluminium has a much lower fatigue life compared to steel. But the real difference is the frame design. If the frame can be made with large diameter tubing, aluminium should work fine, although the ride probably be more harsh. Again it is dependent on the frame geometry.

As far as disc brakes go, discs are a more elegant engineering choice. Discs can be replaced fairly cheap. When a rim wears out, there is the higher cost of the rim and the rebuild cost. On crazyguyonabike, there have been more than a few reports and pictures of rim breaking due to brake wear. Another consideration is the fact that the rim design can be of any shape. A slight aero shape of the rim might be one positive thing, and the freedom to make the rim stronger.

Why spend big bucks on a frame that has a very real chance of fatigue and early death? To save 1 pound off the weight of the bike? Nay, say I. Get the steel, it can take the pain. You can put your fancy parts on it once the stock ones die, or just replace 'em if you're rich!