Light camera bag for cycling

I am looking for a camera bag for cycling trips. I will be riding my mountainbike in the forrest (mainly on the dirt roads) and normal paved roads.

I am thinking that a backpack might be the best solution. It must hold only a few things: Canon 450D, Sigma 18-50 lens and Canon 55-250 IS lens. Maybe even just the 55-250 lens.

It needs to be light so I can breathe through it.

Any suggestions?

I use the LowePro Slingshot 100 AW and really enjoy it. I believe it should hold all the gear you mention in post (I can comfortably fit a 450D, 18-55 is, 18-200 is and 50 f1.8). I have used this bag for skiing and it was nice and light and plan to use it soon for cycling as well. It is well designed.

Good luck!

Yeah I'll second the Lowepro Slingshot 100 AW, handy size not too big not too small, all weather cover as well could be handy while cycling.

I have used the 100 AW and now the 200 AW and I agree they are the best, BUT I would not use them for cycling. Walking around they are great. On a bike where you are rarely upright and often leaning forward, the Slingshot will, sling. Not a good solution. I would look for a holster bag that you can mount on your handlebars (or whatever they are called these days). Look for one that opens/closes easily, with one hand, that perhaps you could reach into and return your camera without needing your other hand. I would vote: one lens, mounted. If a second lens is needed, carry it in some other bike mounted pack. Your body generates heat when cycling, you don't want packs next to your body holding in the heat, or weight shifting throwing you off balance. (My 2 groszy--YMMV-(Your millage may vary)). Doug

Lowepro off trail 2....you can put it on your waist.....

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Canon EOS 400D/XTI + 50mm f1.8 + Sigma 18-200 OS
Panasonic LX3
Canon IXUS 880IS
Canon HG10 HD camcorder

I second the handlebar option for three reasons

1) Personal safety - the last thing I want between my spine and the road is my 400D and 24-105 L walkabout lens. Owwwwww!

2) Personal comfort - I get hot and sweaty enough on the bike as it is without needing a back pack to make matters worse!

3) Kit protection - Kit stowed in a shower proof handlebar bag (I am in the UK and use an inexpensive Halfords own brand one) is quite well protected from shock and from more serious damage if I drop the bike.

[Edited for smellling pistake]

Thanks! I will look into a handlebar solution, I wasn't even aware that such bags exist.

The selection locally where I am is not always great and I may need to look online. Any suggestions on brands and models?

Any time.
I hope you find what you need.

As an example, this is the one that I use: http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_389953_langId_-1_categoryId_165643#dtab

The only modification to the bike that I had to make was to remove the front white reflector (previously mounted on the handlebar) and replace it with one clipped to the offside (the side nearest the center of the road) front fork.

Fitting the bag (which itself has a white reflector strip as you can see) was easy; one bracket on the handlebars that needs two bolts doing up, and that was it! The bag simply clips on and off and when on is completely secure. Because the bag is quite close to the handlebar pivot point and I never load it with more than a couple of kilos of camera kit plus a drink bottle the affect on the bike's handling is negligible.

A fourth benefit of the handlebar bag solution that I didn't metion before; ease of getting the camera out quickly compared to taking a back pack off first.

[Edited to add fourth benefit]