I need a new seat bag for my road bike. The zipper is showing signs of imminent failure on the old one. But, I'm starting to think the bag I'm searching for no longer exists, so I'm wondering if anyone here knows of one that has what I'm looking for.

I need something large, with at least 90 cubic inches of storage. But it needs to be narrow enough at the seatpost end -- 2.5 inches wide at most -- so that my legs won't hit it every time I pedal. And I'm looking for something with a horseshoe-shaped zipper, like the one on this bag, so that you can easily see and access the contents of the bag.

http://www.topeak.com/products/bags/...k_large_velcro

This Topeak bag would be perfect except it is too wide at the seatpost end. Banjo Brothers also makes one that looks great online, but it's also too wide.

My old bag is a Bontrager, and it was fine except for the failing zipper. It has the right kind of zipper and even has a few inside pockets to help organize things. But for some deranged reason, they went backwards in the design and went back to the zipper placement that makes it really hard to get things in and out of the bag.

This Specialized bag shows the inconvenient zipper placement I'm talking about:

http://www.specialized.com/us/en/ftr...at-bags/wedgie

You have to take everything out of the bag to find what you're looking for.

Ironically, the smaller Bontrager seat bags still have the useful zipper placement as well as the inner pockets. But the larger ones, which would benefit more from easy access and inner pockets because they hold more stuff, no longer offer these useful features.

In addition to the large size, horseshoe zipper and narrow 2.5"-width at seatpost, I also need something that attaches to the saddle rails with velcro straps. Due the size and shape of the rails on my Affinity RXL saddle, a bag that attaches like this one won't work:

http://www.rei.com/product/825303/no...nding-seat-bag

(I thought about trying to make the REI bag work by getting longer screws for the attachment mechanism, but the bag is too wide at the seatpost.)

So, I've looked at Topeak, Specialized, Bontrager, Banjo Brothers and the bags that TE sells. I've browsed the seat bags for sale on Amazon. I even looked in the bike accessory aisle at Walmart. I'm not finding anything.

Does anyone know if the bag I'm looking for exists out there somewhere?

Thanks very much.