Gentlemen,

I came across the term "Italian stage geometry". Is this a real term that is measurable in ride quality?

Thanks!

Yes, I'll get the mathematical formula for you a bit latter tonight

Cinelli is an interesting example, things after 1978 got much steeper and shorter, prior, Cinelli was considered "old School" hand had not kept up the current thinking, a frame from the mid 60's to mid 70's is not much different, chainstays a bit shorter, but not by much.

Interesting - maybe I'm a little confused...I thought the stage race frames were fairly relaxed by comparison to a criterium frame (though not anything like a touring bike). Frank Berto's 1988 book when discussing racing bikes describes typical Italian frames as stage race frames and typical Japanese frames of the period as criterium frames with much steeper geometry. Of course it depends on what period we're talking about too I guess.

How would an actual Italian stage race frame compare to a production Italian frame that a regular person could buy in the late 60's - mid-70's? My production bike has what I would consider fairly traditional Italian geometry for that period - 58.5/58.5 ST/TT and 73/73 ST/HT angles, 43.5cm chain stays. I don't remember the wheelbase but I think it's 40-inches or so. I'll have to check.

My understanding of it is seat tube and toptube measurements roughly the same, like 54x54, 55x55.5, etc. no 53cm seat tube with a 56 toptube. Angles were relatively slack, parallel 73's, or in that ballpark. Fork rake and trail combinations that would offer stable steering, not superfast or twitchy, but not sluggish either. A bike easy to sit up and ride no-hands, and keep a straight line.

Along with that, chainstays long enough to provide a wheelbase long enough to stretch out and absorb bumps and rough pavement, have a little flex to offer a little comfort.

In short, a bike comfortable enough to ride all day, but still sporty and responsive, not slow and sluggish like a touring bike.