The trio have some high profile help along for the ride. Chalky Carr Trust Patron and Black Sticks legend Gemma McCaw, Olympic rower champions Eric Murray and Hamish Bond, Ironman champion Hannah Wells, Coast to Coast winner Dougal Allan and Ironman great Cameron Brown will get on their bikes to support the 24-hour bike marathon.
Preparing himself for this gruelling challenge, Gill says getting on the Watt bike for a full day is nothing compared to the grit and strength shown by his mate Chalky in his own battle with pancreatic cancer.
Gill is aiming to beat the current record of 755km cycled in 24 hours.
The group will start the Watty Challenge tomorrow at 7pm and will finish 7pm Friday and a Givealittle page has been set up for donations.
You can follow the trio on Facebook @NicGill @chalkycarrtrust and on Instagram @nic_health_and_performance.