You've missed a trick there, T.I.B.
This year's Exeter Trial started a couple of hours ago, and the last competitor starts at 2.08 tomorrow morning.
Did that & Lands End Trial many years ago on most inappropriate mounts - Maicoletta Scooter and Austin Healey 3000, and they're the most fun you can have. Yes, it's a bit cold at this time of year, but that's the challenge - Lands End is at Easter, which can be just as cold!
Get a roadworthy bike and enjoy.
BTW - how would you get your field bike to South & West Surfers territory?