You can use ridewithgps.com to map out your route. It will have the trail on the map. Finding the trail head in Reedsburg can be a little tricky. I’m sure you’ll find it and will not get lost once you’re on the trail but you may like to note the distances in between the towns and tunnels.
I like the "400" trail from Reedsburg to Elroy and the Elroy/Sparta trail. I don’t know where you are staying but one of my favorite trails in the area is the Great River Trail out of LaCrosse. If you make it all the way to Trempealeau/Perrot State Park, then you’ll want to hike up to Brady’s Bluff where the view is outstanding.
I have a road bike and a hybrid. My hybrid has 700x32's and is perfect for the trail. I would hesitate to use my road bike with 23’s but have seen others that use them—I see them because they usually fly by me and never had to pick one up from the trail later. We've had a lot of rain so I expect a high mosquito population so bringing repellant or not taking breaks may be a good idea. Have a great time!!!