It's late October and I am unwilling to let go of riding season up here in Michigan. Honestly, we use the camping cabins this time of year nowadays simply because both my wife and I are getting older. But tent camping can be done in the colder temperatures, it just takes different gear.
First, you need a 4 season tent. These tents have rain-fly's that reach to the ground and vents that can be closed. These tents can be bulkier, and are certainly more expensive than a summer only tent, but are well worth the expense. Don't skimp on a tent for fall/winter camping. You do not want a tent that will fold under a November storm.
Second, you really need to take double the ground sleeping pads. having more insulation under you is important to keep it from sucking the heat out of your body. You would be surprised as to how fast a good cold weather sleeping bag can go from warm to cold in 4 short hours directly on the ground.
Lastly, a GOOD cold weather sleeping bag. Something rated down to the temperatures you will be expecting. I also bring along summer fleece bags as well because you can get inside that bag and then inside the big bag for lots of extra warmth.
This presents a problem on the bike. you will be taking extra gear to deal with the colder weather. the nice small sleeping bags have to stay home in favor for the big bulky cold weather bags as well as any extra gear you need for cold weather. This can really present a problem if you are a purist and want everything on the bike. 1 up camping is not much harder, but trying to ride 2 up with 2 fleece bags, 2 cold weather bags, a heavier tent, extra sleeping pads, etc... suddenly becomes a big problem. DO NOT get clever and tie anything to your forks. the last thing you need is to add weight to the forks or pus something up there that can jam steering. Also watch your center of gravity, the extra gear can make the bike really top heavy and twitchy.
