I haven't ridden Gargamel in ages - last time we pedalled up from Cougar Mtn on AM bikes and I remember feeling a bit outgunned on some of the features. But now I'm riding better on a better bike. I also recall thinking that the road is very driveable. Any thoughts on dragging a big bike up there vs going AM? I'm not against climbing, just thinking it might be nice to have a bigger margin for error.
With the chunk of singletrack climbing at the start I'd probably just go for the AM bike and enjoy the whole trail. You do need to be pretty confident in pointing and shooting the steeps on the little bike though, and big sticky tyres would be nice (but not essential - there were some serious pinner tyres racing it this weekend). The descent is definitely steep enough, and rough enough, to have fun on the big bike should you want to go for that though.
If you do want to go with the big bike shuttling is pretty easy with the recent road work - although it's steep enough at points that you'll probably want 4x4, you don't need crazy ground clearance anymore.