If you wanted to do some handicapping for the later races- maybe have 5/6 or some other fraction of the rider's time slower than winning time from the last race subtracted from current race time for purposes of awarding prizes. That way, there's always an premium on being the fastest guy out there, but it compresses everything so people who improve week to week can get a shot.
I would still recognize/award the top 3 actual times too, but this way there's a bit of bigger contest pool and competitive aspect for the slower riders.
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