In reply to Tall Clare:
The killer loops from the VG Dales guide are excellent - the second one round Appletreewick/Pateley/Scarhouse is long but non-technical apart from a couple of short sections (drop to Scarhouse and then down to Nidderdale). Mostly stone based tracks too so good all year round.
The medium loop from the marathon a couple of years back might be a good one too - I can't find the route online any more but starting from Kilnsey it climbed Mastiles lane then went over Hawkswick Clowder down to Arncliffe, up Littondale, over the bridleway to Dale Head, then worked its way round the bridleways to Stainforth, back up to the Gorbeck Road and back to Mastiles lane to finish. Could be pretty boggy in places at the moment - worth waiting for a freeze or summer.