DSLR vs compact camera
Choosing whether to use a DSLR or compact (meaning roughly credit card sized, thickness varies) camera usually depends on what type of pics you anticipate taking - mostly fast action pics where the subject is moving or mostly landscape pics where the subject is stationary.
DSLRs are best for the fast action pics, since they can take many frames per second, depending on the model, and have little shutter lag. Disadvantages include large size and possible/probable sensitivity to damage while bouncing around while riding off road motorcycles - they aren't designed for that kind of "abuse".
Compacts are best for landscape pics, as I see it, since the subject doesn't move, and shutter lag doesn't matter, and compacts are much easier for me to carry around due to their small size. Usually compacts have 3X optical zoom; ignore any claims of digital zoom as that's irrelevant marketing hype.
Since my picture taking, while off-road motorcycling, consists mostly of landscapes (as opposed to pics of fast moving subjects, although I take some of those), I use a compact stored in its velcro case zip tied to the chest protector front. Easy to get the camera in and out, even with gloves on. Light and compact. And I've chosen the Olympus SW line of compact camera, since it is designed to be more shock resistant and waterproof. Takes good pics and has lasted two years on the trail so far. Previous compacts (a Minolta and a Casio) failed after a few months of bouncing around and other abuse for which they weren't designed, like when I accidentally dropped it on some rocks.
Remember also you can (depending on the camera features) use a DSLR or compact in movie mode, as well as for still pics. This mode could be useful for some "fast action" stuff, particularly with a compact with its inherent shutter lag.
I don't crash often but when I do its usually a yard sale. So being tough might be a good option.
It would be easy to get a pic of a failed attempt. 
