Ride the Summit Sixty-Five http://65.summitmtb.co.uk/
Hi Graham
Good to bump into you yesterday near the Hale - trails were beginning to dry out nicely

I had no idea of Cleland Bikes, Aylesbury
http://clelandcycles.wordpress.com/ and the history surrounding early British off-road riding in the area - great stuff!
As I said my club, friendly Summit MTB
www.summitmtb.co.uk also rides regularly in the area, across the Chilterns and beyond and always welcomes new riders. Check out our website for regular, open try-out rides.
I'm also the event organiser for the Summit Sixty-Five, an MTB/off-road Sportive
http://65.summitmtb.co.uk/ taking place on 17 June from Cressex School in High Wycombe in support of the Air Ambulance and Summit's British Cycling Go Ride initiative (promoting youth MTB/off-road riding). We're also working in partnership with Wycombe District Council to get more folks inc kids out on the trails on their (MTB) bikes.
We've 3 cracking routes lined-up from a challenging 65 miles to a youth/family friendly 15 miles with an intermediate 40 miles (65 km). The routes will be fully waymarked and comprise the Chiltern's best woodland and tree-lined singletrack, linking classic Chiltern byways, bridleways and quiet country lanes.
Unfortunately I can't make the ride on 20 May as I'm headed to the Test Valley Tour Hot Challenge but I'll look out for the next local ride.
Finally the owner of
http://www.on2wheelscyclery.co.uk/ in Bourne End nr HW, Rich Key (a Summit member) is a vintage/retrobike enthusiast and very experienced in vintage and classic repairs.