A couple of years ago I decided to get a rack on my Trek FX7.2 to enable me to carry more stuff when using my bike for commuting or running errands. Since my bike is a Trek, I got a Bontrager rack. However, to save a few dollars I ended up getting some semi-decent bike panniers from Banjo Bros. to tie me over until I figured out what I really wanted.

This past April, there was a sale going on at Freewheel Bike on the Bontrager trunk bags. My friend Chuck has an Interchange bag and loves it. So I decided to head over to the store and check out the selection and see if I found something I liked. I did some examinations of the three different models, and as soon as I showed my wife the features on the Deluxe, she insisted I invest in the higher end model. I’ve been using it for a few weeks now, and I couldn’t be happier.

The Bontrager Interchange Deluxe Plus rear trunk bag is the top of their Interchange line. The Interchange series simply means that it hooks into a Bontrager rack easily and quickly, without any velcro straps. The front of the bag hooks into the front metal loop on the rack and then it clips into place on the rear. It’s a super simple system, and it’s solid and foolproof.

The main compartment is around 10L of capacity, and I use it to store all the essential bike gear, such as tire levers, CO2 canisters, and a spare tube. The beauty though, of this model, is the expanding side panniers that allow you to increase your total storage to a full 36L. You unzip the side pockets, and they expand into a full pannier on each side that velcro’s to your frame at the bottom. It’s quick and easy to expand, as well as simple to pack away again.

I used this rack for a shopping trip this past Sunday and the expanding capacity was perfect. I used a single pannier for my laptop on the way down to the co-op and coffee shop, but then once I finished shopping I extended the other pannier and loaded it down with groceries. I also had a fair amount of space left over in the main trunk that I could use as well. It was the perfect amount of space for a small grocery shopping trip. If I hadn’t had my laptop with me, I could have even fit more into my bags, but as luck would have it, I didn’t need the additional space.

My bike was pretty weighed down by the time I started heading back home, but the bag stayed put, and I never noticed any type of rattling as I rode. As I rode I also encountered another wonderful feature of this bag… a rain cover. I came across a short sprinkle on my journey, but all I had to do with pause quickly and pull out the hidden rain cover that is stored under the lid. It doesn’t cover the side bags, but the main trunk stayed nice and dry.

Despite the expense, I can’t say enough good things about this bag. I love not needing the full panniers for most casual rides, but love the flexibility to expand my storage when I need it. I’d recommend keeping your eye out for a sale to ease the sticker shock, but even at full price, it’s a great piece of gear that I hope to use for a long, long time.