How long does it take (usually) to bike from Kelowna to Penticton on the Kettle Valley railway? The riders are fit and experienced and won't be stopping long at Chute Lake.
You've got a long ride uphill from Kelowna to the KVR, probably take 2-3 hours, then you can get down to Penticton along the KVR in 2-3 hours, but might want to take 3-4 hours to really enjoy it.