RIVERSIDE (CBSLA.com) A group of 40 cyclists set off from Riverside Plaza early on Sunday morning to cycle 100 miles for charity.

The main challenge?

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Temperatures will come close to 100 degrees. (A high of 98 is expected in Riverside).

For the seasoned cyclists taking part in the 100-mile ride, hydration is essential. One rider told KCAL9’s Joy Benedict that he plans to take advantage of pit-stops along the way, including hydration stations.

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Under ordinary conditions, about 50 cyclists show up for the 100 mile ride, but some were apparently deterred by the prolonged heat wave.

The fifth annual “Citrus Classic Bike Ride” benefits the Riverside Unified School District’s Educational Enrichment Foundation.

The event also features 50, 28 and 7-mile races, taking participants on circuits through parts of Jurupa Valley, Moreno Valley and Highgrove.

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