Bought a used pannier on ebay - can't get it to work!
 

I finally bought the commuter pannier by Two Wheel Gear that I've been drooling over for the past several months. I bought it used on eBay to keep the costs down. It arrived today!

My problem is that I can't get it to work on my bike rack. I was hoping someone here might be able to help me figure it out.

Here's a picture of how it's supposed to work: http://www.twowheelgear.com/faq.php#rack

My problem is that while strap 1 and strap 2 are joined by a velcro piece that can be used to adjust the length, when it is extended to its longest, the J-clips won't reach the top of my rack when the bottom D-ring is in place. I thought the straps would be "stretchy" - but they are not.

Interestingly, when I got my new bike, I couldn't seem to fit my old bike rack onto it (it wouldn't fit over the wheel) even though the LBS guy said that racks are pretty much universal. I tried a different rack and it worked. I think my new pannier would fit on my old rack.

Any thoughts?

The simple representation of the mounting arrangement provided by the manufacturer leads me to believe that they've been inspired by the old Jandd attachment system. Otherwise, I'm not familiar with Two Wheel Gear. Take a look at the mid page section of the link I provided and see if yours works like the Jandds.
http://www.jandd.com/Technotes/technotes_panniers_1.asp

What is the measurement from the top of your rack to the lower pannier attachment point? What brand and model of rack?

http://www.twowheelgear.com/photos/photos/IMG_03.jpg shows it a bit better. And in that pic, with the lower D ring in place, the velcro has LOTS of room to expand. I cant understand why yours is so far different. Is your strap system arranged the same as this pic?

Also make sure its hooked to the bar that kicks out near the bottom, not at the bottom itself.