Commuting bag recommendations

[shekie777]

I've begun commuting to work, will likely do this through autumn, but not in winter.

I have a steel frame Jamis road bike with aluminum seat post, and I would like to attach a bag to the seat post without having to resort to a rack, as this is my "fast" road bike and I don't want to have to keep putting on and taking off a rack. I will be putting into it a polo shirt along with lunch and snacks, and a spare tube, levers, CO2 canister & trigger, mini-tool & eyeglasses. I won't need room to transport shorts/pants or shoes as I'll keep them at work.

I'm considering a Topeak Dynapack:
http://www.modernbike.com/topeak-dynapack

or a Banjo Brothers Saddle Trunk:
http://www.modernbike.com/banjo-brothers-waterproof-saddle-trunk-black

I'm not sure how much room I need for the items described above, or which might make more sense for my application. I'm also open to other suggestions if someone is using something else they like that fits my needs. Thanks.

[eddief]

Uses small bracket bolted to seat rails and has a quick release. Comes in a couple of sizes. Works well. I now use it and a top tube bag on my credit card tours and no longer use any sort of rack.

https://www.google.com/search?q=ortlieb+saddle+bag&tbm=isch&imgil=Zzh4l9lgmAdfyM%253A%253Bhttps%253A%252F%252F encrypted-tbn0.gstatic.com%252Fimages%253Fq%253Dtbn%253AANd9 GcQ6kxNTZUZ3xOfVERzJghLoximUElaqQyFWfKCc6rgUB26WPJ 24%253B600%253B400%253BA-R4etSiFkW4eM%253Bhttp%25253A%25252F%25252Fglobal.r akuten.com%25252Fen%25252Fstore%25252Fbebike%25252 Fitem%25252Fortlieb_f96ls%25252F&source=iu&usg=__1XVD9LYx9YyvWmtsYBARN3S1xL8%3D&sa=X&ei=dm_SU9LBFsLZoASIuIKIDA&ved=0CFYQ9QEwBA&biw=1255&bih=551#facrc=_&imgdii=_&imgrc=Zzh4l9lgmAdfyM%253A%3BA-R4etSiFkW4eM%3Bhttp%253A%252F%252Fimage.rakuten.co .jp%252Fbebike%252Fcabinet%252Fortlieb%252Fortlieb-f96ll-4.jpg%3Bhttp%253A%252F%252Fglobal.rakuten.com%252F en%252Fstore%252Fbebike%252Fitem%252Fortlieb_f96ls %252F%3B600%3B400

[dawgie]

I've bike commuted for many years and tried all sorts of bags. For me, the most convenient option is a Carradice Barley seatbag with their Bagman rack with quick release. The Barley holds everything that I need 99% of the time, and is very easy to install and remove with the quick release rack. Carradice bags center the weight near your saddle, so they have less effect on handling than racktop bags.

[ceolwulf]

Now I just wear a messenger bag but I used to use this saddlebag for your exact purpose:

http://store.velo-orange.com/index.php/accessories/bags-panniers/minnehaha-medium-saddle-bag.html

You also need a Carradice adapter if your saddle does not have bag loops.