Hey Greg..yeah the H4N is about $300. I have it for doing DSLR video...so I'd thought I'd use it. But, they also make a $100 version, the H2, that does pretty well. The GoPro2 has an external audio jack..so I'll try that with a mic next. The big secret isn't the H4N..it's the Redhead wind screen. Check out the demo video on http://www.redheadwindscreens.com
Syncing is actually pretty easy. I use Adobe premiere...and most of the time I just sync a few mouth clicks at the begining. If I have a lot of tracks over several days (like the snowboard stuff ) I'll use a program called DualEyes that automatically syncs and replaces the audio. You still need to through in some clicks or claps to help the program out. But most of the time if it's just one track, I'll drag it into Premiere and just match up the waves visually...it takes maybe 30 seconds.
The camera was mounted on a Manfrotto monopod that was ziptied to the frame. I was worried about a crash when I strapped it on there...so I used a releasable zip-tie at the top so it would flex if in a crash. I've found the releasable ones will give fairly easily. The h4n was sitting on a mini table top tripod velcrod to the top tube.
I've tried the chest mounts before but find the constant swaying annoying. I've been experimenting with mounts on the bike. So far this has been the best. Part of it has to do with the handlebars moving exactly like the camera...so you get an intrinsically stabilized foreground reference point. Then, all the CMOS rolling shutter jellies and background vibrations don't seem so bad. Plus it gives a frame of reference for the viewer. I want to experiment more with 3rd person type viewpoints...hanging the camera off behind or to the side.
You know, one of the first things that went through my head after the crash was your recent video of a wash out: where you pointed out how much gloves minimized the damage of the accident.