My self-contained summer touring pack, good to 30 degrees F, weighs less than 14 pounds. I'd need to add over a pound to take my 15F bag along. That includes packs, tools, spares, lock and lights, but not the rack which is never removed.
By comparison, my backpack (for long distance trails) weighs about eight pounds for the same conditions, so the bike almost doubles that weight, mainly because of the tools, spares, and lock. I carry an extra jersey for mountain descents.
If I'm riding unsupported, I carry two pounds of food per day, and as much water as conditions require, seldom more than three liters though I have capacity for five liters. But I often tour with little more than lunch and a sip of water, if I'm in civilization most of the day.
I've perfected a stoveless travel style over the years. That, along with using a single-wall shelter, was a big factor in weight and volume reduction, allowing me to travel without front packs.