He completed his 250 miles yesterday (Monday), with a 23 mile ride and finishing his challenge with nine days to spare.
The challenge was even more tough for Duncan, as he was diagnosed with Charcot–Marie–Tooth disease (CMT), a hereditary muscle wasting disease his father also suffers from.
He said: "The challenge itself went fantastic,the most challenging ride was out in the Vale of Belvoir which was very hilly and it was a scorching hot sunny day, the rain we had put me behind , but I soon caught up."
Duncan completed the last 23 miles yesterday with a ride across to Newark and then back again through Claypole and Stubton.
To help boost Duncan's fundraising, his employers at the Waggon and Horses pub in the village organised a fundraising event held at the pub over May Bank Holiday weekend, which raised around £600 towards Duncan's appeal.
"It's been a real honour to raise money for such a fantastic charity, with my sponsor money and the money we raised on the charity weekend we made nearly £1,000," he added, "I can’t thank people enough for their generosity."