Originally Posted by
seau grateau
Yeah, I hear a lot of people lately using stack and reach to size frames rather than TT length. I thought a 49 sounded way small until I looked at the geo chart and saw that their size labels come from the seat-tube length. Still don't understand why companies do that.
This seriously baffles me too, especially when 1) it ignores seat tube angle and 2) always measures center-top, which is highly arbitrary. It might have made sense when frames tended to use the same angles and the seat tube stuck up a standard height above the top tube, but these days it's totally unworkable. I can see why it's a useful measurement for the
builder, but not for the consumer.
In fact, I'm shocked in general that a more sensible and standardized system of measurement and spec presentation hasn't caught on.