I identify with the clydedales, 50+ and touring forums, but feel most comfortable sharing this with the clydesdales.
Earlier this month I spent 4 days riding 200 kms and camping on the Kettle Valley Railway and then another 2 days riding 100 kms on the highway back to my car.
Our route, from Penticton to Rock Creek on the KVR, and then Rock Creek to Penticton on the highway had every trail condition conceivable. Soft sand, hard pack, washboard, and pavement with wide shoulders. We camped in private campgrounds, a provincial park, and a wilderness site on a high elevation lake.
The best website and book for cyclists is at: http://www.kettlevalleyrailway.ca/
You can enjoy the trestles of Myra Canyon on a day trip from Kelowna, and drive to Chute lake, Mc Cullough Lake, Beaverdell or Rock Creek to ride local sections of the trail. Myra Canyon is the most visited, but the lakes have a quiet beauty all their own.
Going up hill from Penticton to Chute Lake is particularly difficult in the soft sand, but cyclists going down hill on that section had no problems.
Water is scarce so we carried 3 liters (quarts) each per day and needed all of it to get from Penticton to Chute Lake.
As a clydesdale, and rookie cycle tourist, I recommend this trip for those wanting a challenging self contained tour, or a day ride on a historic railway.