The "Engineers" thread made me think that there is enough of a nurd-ish group here that might enjoy these bike tools. Only for the truly obsessive.
The best general bike website: http://sheldonbrown.com/
The best bike gearing tool: http://home.earthlink.net/~mike.sherman/shift.html
Another good tool to be used in combination with the above: http://www.kstoerz.com/gearcalc/compare/
A good bike fit calculator: http://www.competitivecyclist.com/za...LCULATOR_INTRO
What you need to know about modern steel frames;
In terms of overall tensile strength, here is the order from strongest to weakest of common bike tubing steels;
1. Heat-treated air hardened steel (Reynolds 853, Columbus Foco, TrueTemper OXPlatinum)*
2. Heat-treated CrMo(Tange Prestige HT, TrueTemper Verus HT Reynolds 725)
3. Cold-drawn air hardened steel (Reynolds 631)*
4. Cold-drawn 4130 CrMo(Reynolds 525, TrueTemper Verus, Tange Prestige/Infinity)
5. High tensile steel(cheap dept. store bikes, cheaper bike shop bikes)
* Air-hardened steels actually gain strength in the weld area after welding, but not along the whole tube.
Modern Reynolds steel: http://www.fairing.com/Reynolds.asp?...ubreynolds=631
Vintage Columbus steel: http://www.equusbicycle.com/bike/col...umbuschart.htm
Bike Fork Trail Calculator: http://yojimg.net/bike/web_tools/trailcalc.php