The original Daytona race track was quite a challenge . Both long straights ( 2 miles up and 2 miles back) were difficult. The Beach side was not always packed sand, you had to worry about low and high tide and spectators on both sides who sometimes would foolishly cross the track, too many times with fatal consequences for both riders and idiots.
The paved side was rough with wind blown sand making traction scarce. The two corners were sand that could get very deep and treacherous. This only added to the fun and the Beach races were wildly popular with racers and spectators alike for over two decades, '37-'60. The new Super Speedway promoted all Motor Sport to a new level but lost ,was the close up spectacle of the Thrills and Spills of racing at The Beach .
Vincent Grey Flash, Norton Manx, Harley K Model. The pack is running in the wet sand because the slow guys have gone up high onto the hard pack and blocked the fast part of the course. Great differential in speed was just another serious factor to contend with.