Rear Trunk Bag for Narrow Cargo Rack
 

I have a nifty little rack for my roadie; a 'Bontrager Backrack Lightweight' that mounts using the rear skewer.

I realize that this is an "Interchange" type rack that can mount Trek/Bontrager's line of easy off & on racks.

However, I want to get a non-dedicated trunk bag (with standard mounting straps) that I can also use on other racks/bikes.

This rack's width is relatively narrow, about 3.25" at the tail end, 4" at the front so, it's not perfectly rectangular.
--The Ortlieb Trunk (with the smart adjustable gizmos underneath) does not fit due to the non-rectangularity of the rack.

Any suggestions for a sleek (non-shoebox) designed bag would be greatly appreciated

I like these guys: https://www.axiomgear.com/products/bags/trunk-bags/

You can find them cheaper on the web.

I like the Banjo Bros rack top bags. Inexpensive and well built. I use the rack top expanding bag for commuting.

I own this exact MEC model. The Banjo boys ones look good too.


MEC's catologue still stocks that bag but the design is slighlty different now.

The Ortlieb Rack Lock system should work on just about any rack. The locking tabs adjust independently so you should be able to adjust for a rack that isn’t square. Just move the front tabs inboard a little.

Thx. That's a nice waterproof bag, but I contacted Ortlieb and they advised against it for this rack, as well as for my Topeak racks...
I examined the Ortlieb Rack Loc video and it appears the clip-locks move independently in pairs, left & right, and unfortunately, not front & rear.

If you have an REI nearby, you could try it to see if it would work. Tubus makes racks that aren’t square either. For example there is a 1/2” difference between the front and back of the Vega. The Fly has a 1” difference. The Ortlieb bags are designed to fit on Tubus racks.

Great idea! Thx...

Arkel Tailrider for me and my wife. We love them, and they fit quite a large volume.

I just last night added a narrow seat post rack on my road bike and put a bag on it. I decided to affix it permanently, and so not much point in buying something with mounting brackets, quick releases, and so on. A light bag/pack, coroplast cut and shaped inside it for a semi-aero look, ziptied down and done. The look is more sleek and less bulky and not as boxy, and likely lighter, than retail trunk bags IMO. I could fill the whole bag up if I want and it would still be secure but the 4 or 5 inches height of the sides is mostly enough.


I'll maybe post up some pictures later, but the DIY route is something to consider. I've used the bag for years, basically zero cost, and start to finish took about half an hour, so who cares if it's out in the weather - no reason to remove it.

might as well contact these ppl & ask them what bag goes with that rack

https://www.trekbicyclesuperstore.com/

& these guys say that rack is compatible with Interchange trunk bags

https://www.trekbikes.com/us/en_US/e...olorCode=black

Thx. I owned a Trek Interchange style bag in the past and it kept falling off the rack when I hit bumps.

oh OK, that's too bad. FWIW even tho my trunk bags have generic Velcro straps I also always use 1 or 2 short bungee cords for security. I can also tuck a jacket, hat or rain cover under the bungee

https://cimg2.ibsrv.net/gimg/bikefor...59ca335b39.jpg

I think I got this little Bell brand trunk at Walmart

https://cimg9.ibsrv.net/gimg/bikefor...4de778afd8.jpg

https://cimg0.ibsrv.net/gimg/bikefor...f169024782.jpg

that wire extension is for when I use a bigger & longer trunk

https://cimg2.ibsrv.net/gimg/bikefor...e2f66cb437.jpg

one side of this trunk's velcro straps eventually tore so I snaked a short bungee into the slot to hold it in place. but not I have a length of 2-sided velcro that runs thru that slot

https://cimg0.ibsrv.net/gimg/bikefor...74527b1b2b.jpg

this was an oldie but goodie. it was def. wider than my racks. cheap bag I got at a low end bike shop for $15. lasted very well thru a cpl years of commuting & still gets use now. I just have to lube the zippers every now & then

https://cimg4.ibsrv.net/gimg/bikefor...4252da0604.jpg

this trunk holds quite a lot & is almost always wider than any of my racks. velcro straps are OK but if they don't match up / line with the slots in your racks, if you have slots, then it may need some extra connectivity

https://cimg1.ibsrv.net/gimg/bikefor...f91b6d8720.jpg

https://cimg3.ibsrv.net/gimg/bikefor...53f6cb4722.jpg

I use the same bag and have the same rack as the OP. Great combination and the bag is awesome. I also use Arkel panniers.

That is a nice bag. Good looking too

For the longest time, I was searching for the perfect rack trunk. But they were always too small for what I needed to carry, like changes of clothes, lunch, laptop and repair kit for comuting to work.

I tried duffel backs but I just didn't like the bungee cord method because you'd have to undo it just take out a jacket or something. I wanted to look for bags that already had side loops so they could strapped or bungeed down without interfering with any zippers. Nobody makes bags like that. Even mounting a knap sack was cumbersome because the shoulder straps would dangle all over the place.

Finally, I settled for the Arkel combination panier/backpack. It's a panier that's big enough for all the things I needed to carry and when you take it off the bike, you unzip to take the backpack shoulder straps out. It even has a loose pocket to store your helmet.

www amazon com/Roswheel-Resistant-Convertible-Bicycle-Pannier/dp/B07CKZ4SH6/ref=pd_lpo_sbs_468_img_0?_encoding=UTF8&refRID=J59PCH6RQ0M0NWEQZBEH

I can recommend this one, really good quality, very water resistant and with a versatile system of straps to fix to the rack. The straps have velcro and also interlock above the bag so it's 100% secure. Mine has over two years of daily use including commuting and dirt road riding and it's still in excellent condition.
The link is the first one I saw. You can get it cheaper I'm sure.

I have one of their basic $35 trunk bags and like it very much. It doesn't hold a lot, just extra tubes, mini-pump, my tool roll, with room for a lunch and a few more things. It is sleek, though, and easy on and off.

The Trek Interchange seems to use a variant of the Rixen Kaul Klickfix system. I wonder if you aren't engaging the catch enough to keep it from coming off. Perhaps a little bit of sandpaper surgery would make it work better.

On the other hand, Rixen Kaul seem to have a new system that might be worth investigating. It's called the "UniKlip" system and looks similar to the Ortlieb system but perhaps a bit simpler.

My solution to the problem that I hit upon about 10 years ago was the Ortlieb basket mount and rack top adapter. The basket mount is bolted to a Racktime Trunk-it (it has a stiff bottom) and the basket mount just clicks into the adapter which is clamped to the top of the rack. I've ridden off-road with it containing a fair amount of stuff and never had it even so much as wiggle. I don't usually use the side pieces for panniers as I don't need them. Here it is in action

https://live.staticflickr.com/4461/3...93ad2485_k.jpgDSCN0387 by Stuart Black, on Flickr

The rack adapter

https://live.staticflickr.com/4877/4...5c3e5a94_k.jpgUntitled by Stuart Black, on Flickr

The basket adapter

https://live.staticflickr.com/4875/3...a8b14a88_k.jpgUntitled by Stuart Black, on Flickr

The picture above is for a micro pannier system I designed for bike packing using a couple of front handlebar pockets

https://live.staticflickr.com/4813/4...c45dbd6f_k.jpgUntitled by Stuart Black, on Flickr

I can't put on a rack bag when I have my seatbag on there

https://live.staticflickr.com/1838/2...dfea140c_k.jpgDSCN1255 by Stuart Black, on Flickr

so the micro panniers mount a little lower and give me just a little more cargo room.

This system is far better, in my opinion, than any velcro system I've ever used...and had to go back and pick up.

I had a Trek basket on my Trek rack that kept coming off. After the first time I assumed I hadn't clicked it in properly. After the second, I knew darn well I had and was aggravated, but was upgrading my bike and agreed to try it on there (same rack, but whatever). After the third and fourth — in the same ride — I took it back. All the guys at the shop could say is, "I've never had one do that. I don't know how it can be doing that", but all the scuffs on the corners proved it spent a lot of time hitting pavement.

I did miss it, though, so now I have a nice wire basket bungee'd to my rack. Prettier than a milk crate.