Hundreds of thousands of motorists who use Interstate 69 northeast of Indianapolis will need to pay close attention to changing speed limits.The speed limit from southbound 96th Street to Interstate 465 is being reduced from 65 mph to 55 mph, but it's being increased from 65 mph to 70 mph on northbound I-69 north of mile marker 6.5.The Indiana Department of Transportation said the decrease is being made because of safety issues, but many motorists think people will drive as fast as they want, 6News' Sarah Cornell reported."They totally ignore the speed limits out there now. I don't think they'll do it," said motorist Carol Hansen.INDOT said the northbound speed limit increase was made because the road is safe enough to do so and most drivers were going that speed anyway."I think as long as it's safe, as long as they get the construction barriers out of the way and it doesn't pose a threat to drivers and pedestrians, I think it would be OK," said driver Greg Schmitz.Changing all the speed limit signs on I-69 will take about a week. In the meantime, police will be watching to make sure motorists are not exceeding the limit that's currently posted."These are pretty minimal changes, and a lot of drivers were already going these speeds anyway. It shouldn't be that much of a challenge," said INDOT spokeswoman Ashley Hungate.Now that construction is completed on I-69 from Binford Boulevard to 116th Street, the speed limit there will go back to 65 mph.