I've been entering the details of my Lemond Sarthe frame (hand built, TIG welding in the USA) into the on line version of BikeCAD and have been surprised at both the difficulty and frustration in reconciling the differences between the published geometry/specs and what I am able to measure.
Many tubing lengths are 1 - 2 mm different and angles are out by at least 0.5 degrees, maybe 0.75 degrees in some cases. Basically, it seems that it is impossible to make it work in Bike CAD without accepting some variation (1 to 2 %). I don't think the problem is with BikeCAD.
How much do the specs vary for various brands of frames, or even between the same models/sizes? How much variation is considered acceptable?
When these bike frames are being assembled, are the last tubes "cut to fit" or is this slop just due to the nature of welding (heating/expansion, etc.)
Does any one know where/who used to build the Lemond steel frames?