will be working in ambleside from mid may and wont have much evening ride time so looking for some 45 min loops (average fitness) i could do from ambleside in a lunch hour. Dont know the area that well but have Mountain bike and cross bike
I recon.. Road out under loughrigg over to Rydal house, coffin road down to Grassmere up red bank through the trees then down the terrace. Should be about 45 minutes plus there are a few variants you can do as well. if you look on a map or after getting your eye in :-).
Alternatly just ask at Biketreks.
Loughrigg loop is about that, climb up loughrigg from rothay park, descend other side, round back of loughrigg tarn on bridleway, up to top of red bank then down terrace and back round caves.
Or ride on A591 south past low wood, climb up Holbeck lane (first left), into troutbeck, then take sharp left at post office, climb up robin lane then descend through farm singletrack, up steep road climb then into skelghyll woods and back down into Ambleside. Great descent. (You'll need to look on a map though after those directions!)
The loughrigg route mentioned above is excellant, though I'd allow yourself an hour first time around