Here is an overall list of the specific dimensions of the "M" Tracks:
Bold denotes full length track sections
5100 Standard Radius Curve (full standard curve)
5101 Standard Radius Curve (half full curve)
5102 Standard Radius Curve (quarter full curve)
5106 Straight 7.08” (180mm long) (full straight)
5107 Straight 3.54” (90mm long) (half full straight)
5108 Straight 1.77" (45mm long) (quarter full straight)
5109 Straight 1.32” (33.5mm long)
5110 Straight 0.88” (22.5mm long) (eighth full straight)
5120 Industrial Radius Curve (full Industrial curve) (286mm 11.25" radius)
5129 Straight 2.76" (70mm long) (special straight)
5200 Big Radius Curve (full big curve)
5201 Big Radius Curve (half big curve)
5205 Big Radius Curve (~1/6 big curve)
5206 Big Radius Curve (~5/6 big curve)
5208 Straight 5/16” (8mm long)
5210 Straight 5/8” (16mm long)