I've fit up to 25 inch frame and fork into a 108" box. I did have to dismantle the bike box, rebuild it shoe box style (bottom with a lid) to get the width of the box down to 7 inches. Just shipped a 22 inch road frame and fork in a 23x8x38 box. Fork has to be removed first and it straddles the ST. The postage break is not just 108" or less. Getting it down to 100 inches total cut the postage in HALF. That being said, its a PITA.
And in the world of shipping, its girth plus length. Girth = the two shortest measurements, doubled, then add length.
If you look at my fold measurements, I was shooting for 22 high, it grew a little in packing to about 22 1/4, which in the land of Fed Ex, is rounded up. Bike boxes at the LBS are often 8 1/2 inches wide (rounds up to 9 inches) or 9 1/2 inches wide, or even higher. Juvenile bike boxes are often 7 1/2 inch wide.
The "best" deal I ever got was shipping a frame to Whitehorse, Yukon, Canada (from my home in NC. 25 inch frame and fork, box built shoe box style, right at the 108 inch limit. Sent USPS Priority, $85.....You are talking almost 6,000 kilometers.
