Frame size / Actual frame size

Vivid Posts: 267
edited December 2008 in MTB buying advice

Just been having a look at the new Trek Fuel EX8 09 model, i am slightly confused by the frame sizes.

The 17.5in frame reads 16.5in actual frame size.

Never seen this before so i would be grateful if someone can explain what is meant by these figures e.g. what frame size is the bike, 17.5in or 16.5in.

Link is below ... /fuelex8e/

Click geometry to see details.

Thank you in advance.