Originally Posted by Arkel
Will this pannier fit my bike
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One of the best ways to know beforehand if you'll have the clearance necessary (short of trying it first hand) is to see if there is an overlap between your ankle and where the panniers will sit on your rack. Each of our pannier models has a blueprints page with pannier and hooks dimensions available. Use these to draw the outline of the pannier on a piece of cardboard and tape that cardboard on the side of your rack, as far back as the position of the hooks will allow. Hop on the bike, backpedal and have a friend check to see if there's an overlap.
If you click on the "Detailed measurements" link on their site for any pannier, you can get details on how draw the blueprint. However, they don't seem to include measurements for where the rack hooks are. Maybe you can contact Arkel directly for that though.
Also does all the Cannondale Caadx lineup have rear eyelets to mount a rack? The pictures for the 2013 models don't seem to show any, but they are fairly low resolution anyway.