Oversized down tube?
 

Ok is it me only but makers are now having their bike done with OVERSIZED down tubes,straight forks tig weld.. what gives..somebody explain this to me .. I can deal with Cannondale OS tubing but.. explain please.

S/F,
CEYA!

Did you do any research? I'm sure manuf. would explain their thinking.

I'm thinking it means Thinner metal/ stronger frame perhaps?

Merlin backs this up, saying: "The newly designed butted and shaped oversized downtube adds remarkable stiffness to the bike."
http://www.merlinbike.com/bikes/2005/extralight.aspx

There ya go.

Let's not kid ourselves- it is all about fashion and making "last year's bike" look old and busted so people upgrade well before necessary. Look how briefly the standard threadless headset was in vogue- to be quickly replaced with internal headsets. Now we have all these oversized handlebars... rendering regular bars "obsolete." Bikes are looking more cartoonish than ever these days. Don't fall for the marketing hyperbole.

I'm not so sure that it's entirely marketing hype. I'd like to think it's more a reaction to the materials being used in bike construction today: what we consider 'normal' tube diameters were developed when steel was all that anybody used, and 'oversize' tube diameters bring out the better qualities of aluminum tubes. Handlebars seem to be a similar case, this time with carbon. It could be that the standard clamp diameters established with steel and aluminum bars were too skinny to safely execute in carbon, so the 31.7 clamp was developed to facilitate full carbon bars.

However... I do agree that integrated headsets and oversized/outboard bearings on cranks *are* crap.

And some eye candy... who you callin' oversized?!
http://www.fixedgeargallery.com/2004/f/benton1.jpg

That's a Spicer - we (DCC) saw that bike in Dec outside of Jinx. It's crazy looking - has the fattest chain ever. Thicker than 1/8.

That's Bill's bike... Chicago dude, super tall, ex-Portland messenger (I think), super cool guy. He says that the downtube certainly is stiff, but borders on being unridable. I think he runs a minimum of 28mm tires just to save his hands.

He should be at the TdC this weekend.

Won't miss him them.

I always thought oversized tubing was just for aluminium bikes like keevhon
but then when I went steel frame shopping I noticed so many of them had crazy
shaped tubing. Personally, I really like the looks of a classic steel road frame.

Now I'm by no means retro especially compared to AL5 and his penchant for
Vanilla bikes & shellac. I prefer the aesthetic of TIG to lugs and carbon
weave looks cool.

Anyways, the crazy shaped downtube of Karstens(sp) was the reason
I didn't even think about Thylacine as a builder, until he showed me
picks of the "classic" road frames he builds.

jeff

My frame is Dedachai OS tubing, lugged, light and stiff. I love it! The tubes are round, not outrageous like those spicers (or 99% of frames made today!), but just a little larger than traditional steel.

These over-sized downtubes seem like a styling trend.
Several frame makers/providers have recently made a larger downtube part of their design; some very subtly and some not so subtly.

Aesthetically, I prefer the traditional designs which have all same size (or close enough so one wouldn't notice it) tubing.
Techone's bike, which he describes as utilizing Dedacciai OS tubing, has that classic look, to me, despite the OS description.

I have not seen a Bianchi Pista in real life.
Mine should arrive at my lbs tomorrow.
From the pictures, though, it seems to have a gradual center bulge (and probably a flattening viewed from the front or rear) in the downtube (oval?).
A person could look at it and not see it, I think.
The recent KHS and IRO frames seem to have a slightly larger downtube; and, again, from photos.
In all three cases, it looks like a styling thing more than an engineering thing.
I'd like to see some engineering data regarding all of this.

The pista's downtube definitely has a "shape" to
it, but not anything too noticible except for when
you pet it to sleep at night.

jeff

The Pista's downtube is slightly larger indeed. At the top end by the headtube it's rounder and as it slopes downward takes on an oval shape (tall) and flattens out a little (makes the decal panel look really nice) and then flattens out widthwise as it meets the bottom bracket. But the tubing looks pretty good.

Alot of frames are looking like this one .. WHY? just like some here have said FAD . I hope so. Stiffer frame Hmm ..maybe Some just look sloppy. Rear ends look terrible.

Big tubes makes Cannondales look better. Even cannondales scaled back on oversized down tubes..little bit.

I will find out why this trend is taking over our classic looks of bikes.

I gettin old .. that is it..

S/F,
CEYA!