Commuting - What adhesive to use for gluing saddle/wedge bag?

I have this bag Shwinn wedge bag (http://canadiantire.ca/browse/product_detail.jsp?PRODUCT%3C%3Eprd_id=845524442204935&FOLDER%3C%3Efolder_id=1408474396672219&bmUID=1183139320960) on my bike and the strap in normal useable velcro is too loose for my suspension seatpost so I over strapped it and it still works but it's right now clinging into the actual fabric for that extra light cling. Not the ideal grip I want. I managed to find some velcro strap from the toolbox and want to glue this to the underside of the bag. The velcro strap I have has a peel and stick backing and I know that if I peel and stick it on the bag and strap on/off the sticky part will just come right off.

I mentioned that sticky part incase people think this is some fabric velcro with non-stick backing. I was thinking of using crazy glue but not sure what to get. I would like to have some adhesive that I can use for other stuff then just gluing this bag when it's done. I know crazy glue can be used for other stuff afterwards. One thing I want is to glue this strap extention onto the bag SOLID. I think the bag material is ballistic nylon because it holds up very well to stretches and such then the other bag I had that broke after it's first use. I will be taking the bag on/off regularly so I need a SOLID adhesive that will bond that sticky backing to the nylon and can handle frequent removal of the bag.

Thanks in advance. Canadian Tire, Home Depot, and Wallys are my major sources here.

I hate websites that make you enter your location before you can look at their products, especially when they require you to enter a Canadian postal code, since I don't know any.

Anyway, assuming the bag is made of fabric and you want to attach other fabric to it, you're probably better off sewing them together rather than gluing them.

+1 on the sewing idea. But barring access to a sewing machine, I'd use Gorilla Glue. You could make Vaseline stick to Body Glide with that stuff.

barge cement or mcnett seam grip.
barge cement is used to hold climbing shoe rubber soles on. I've never found anything stronger.

You don't need a sewing machine. Just get a few needles and a spool of black thread and go to work on it. It shouldn't take a ton of sewing to get it on there.

Oh and another option... instead of adding velcro... bunch the other part of the existing strap a little and sew it together. Then when you close it it'll grip where it's supposed to and no additional velcro would be needed :D

3M 1357 contact cement is the only thing I'd really trust for gluing Velcro backing to ballistic nylon. It's available in 5 oz. tubes; you'd have to find a local 3M adhesives distributor and see if they can get it for you. If your distributor is like the guys I deal with locally, they'll usually just give away small tubes as samples rather than hassle with actually selling it to you.

Barring that, sew the velcro on. Barring that, you could try shoe goo, or any number of other adhesives.

Have you considered just getting a wedge that fits your bike?