Thomas defending against local rivals
More than one thousand competitors are taking part in the Manx Telecom End2End mountain bike race.
The event starts at the Point of Ayre at 10am.
There are a number of changes to the route with the most notable at the end.
Riders will finish on Port Erin promenade rather than at Cregneash.
The change will see a climb over Fleshwick and up to Milner Tower before descending into Port Erin.
Local riders are expected to be challenging for the overall victory and include veteran Elliot Baxter and multiple Island Games gold medallist Nick Corlett.
Reigning Champion Ben Thomas is back to defend his title and confidence will be high having recently secured the British Cross-Country Championship.
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