OK I understand.Not that far for biginners...
The route going to be something like the following.
Start : 津久井湖 (Tsukui-Lake)
end : 宮ヶ瀬ダム (Miyagase-Dam)
There is no Train Station near Tsukui-Lake nor Miyagase-Dam.
So, if you are anxious to find the route to starting point, come to the Hashimoto Staion of Keio-Line (京王線 橋本駅). I can go to Hashimoto Staion and meet with you.
That is a bit far for me to go for such a short ride.
I think my wife has something planned for us for Sunday, our daughter want to do SOMETHING for Golden Week
Hope you have a great ride!