Harlan provides race commentary but is at the finish line and not able to view who is winning while the race is in progress.
When Ponch wrecks his motorcycle, the cable attached to the bike (to keep it from rolling out of control) is visible off to the right as it rolls toward the semi-truck.
When Lonnie is counting out the money to Daws, he says there is $900, but all he has is a roll of $1 bills.
When Ponch is in pursuit, even though we can hear the siren, his red lights aren't activated until just before he wrecks his motorcycle. No officer would ever go into a pursuit without activating both red lights and the siren.