Commuting - Sweat and Messenger Bags

I've been reading this forum for a while but never really had an excuse to say anything, and I've scoured the forum and havent found anything on this so here goes. Some background on me, I'm an obsesive trials rider (I ride ever(other sometimes) day, so I'm in decent shape. I have a short comute its around 5km downhill all the way there, but being the adreneline junkie that I am I have to sprint it all. So when i get to school my back is either wet or soaked from sweat depending on the time of the year, don't get me started on what I look like after the uphill home. So I figured that maybe a mesenger bag might help this, I need to fit a binder or two (14.5"*12") and some other stuff in this but I thought because it's a mesenger bag it might lay a bit more to the side and stop this. Does anyone have any information about sweating with a mesenger bag? I was looking at this one from MEC (http://www.mec.ca/Products/product_detail.jsp?PRODUCT%3C%3Eprd_id=845524441895105&FOLDER%3C%3Efolder_id=2534374302693337&bmUID=1128004920172) because it's big enough and not too pricey, but if need be I can save up the bus money I'm saving for a few more months and put it towards a diffrent bag.

You'll still have the magic sweat patch.

Is there a counter spell to get rid of this? Besides a change of shirt that is.

The only cure I've found is to just take it easy on the ride.

..but I usually forget about halfway through.

Messenger bags are slightly better than back packs for sweat on your back but they still lay against your back so your going to get sweaty. A rack a panniers would be better, you back would be drier but I think you'll still be somewhat damp. My suggestion is to bring a change of shirt.
Craig

I only get wet where the bag is pressing on me, when I'm biking the air is moving fast enough to cool me down, but the bag blocks airflow so thats why I'm only sweaty in this one place.

Paniers would be best, but a change of shirt will be okay as well.

I've seen home-made lifts attached to backpacks that allow space for air to go through. One guy just had a ball of duct tape to lift the pack away from his back. Perhaps some sort of home-made lift would be made for the msg bag.

There are some backpacks which have padded bars to separate the bag from your back, providing a half-inch of more of airflow between.

Messenger bags certainly will trap sweat similarly to a backpack, but I don't really care. I end up pretty sweaty all over, and I change from my cycling lycra into work clothes anyway.

Messenger bags are better than backpacks, IMO, simply because they are much more comfortable on the bike.

- Warren

Messenger bags feel breezier than normal backpacks, in my opinion. I have a rack now, and I thought it would end the sweaty back thing, but it didn't. Although it does make you feel lighter and faster. So yeah, changing shirt in public restroom is best course of action, or just having a little while so your sweat dries.