LabVIEW, 22 equivalent bytes

First we convert to lowercase, then to byte array. Trim off the first element of the byte array as it has no precedent. Then, for each element in the array, check if it's greater than the previous one (U8 char maps to ASCII as you expect) and store the result for the next iteration, as well as in an array for viewing overall bumpiness. If the current and prior boolean check are equal, we terminate the loop and it's not bumpy. Else, it's bumpy!

Ungolfed:

LabVIEW, 36 equivalent bytes

Golfed down using logical equivalences:

Ungolfed:

First we convert to lowercase, then to byte array. Trim off the first element of the byte array as it has no precedent. Then, for each element in the array, check if it's greater than the previous one (U8 char maps to ASCII as you expect) and store the result for the next iteration, as well as in an array for viewing overall bumpiness. If the current and prior boolean check are equal, we terminate the loop and it's not bumpy. Else, it's bumpy!

LabVIEW, 33 equivalent bytes

First we convert to lowercase, then to byte array. Trim off the first element of the byte array as it has no precedent. Then, for each element in the array, check if it's greater than the previous one (U8 char maps to ASCII as you expect) and store the result for the next iteration, as well as in an array for viewing overall bumpiness. If the current and prior boolean check are equal, we terminate the loop and it's not bumpy. Else, it's bumpy!

LabVIEW, 22 equivalent bytes

First we convert to lowercase, then to byte array. Trim off the first element of the byte array as it has no precedent. Then, for each element in the array, check if it's greater than the previous one (U8 char maps to ASCII as you expect) and store the result for the next iteration, as well as in an array for viewing overall bumpiness. If the current and prior boolean check are equal, we terminate the loop and it's not bumpy. Else, it's bumpy!

Ungolfed:

LabVIEW, 246.5KB

First we convert to lowercase, then to byte array. Trim off the first element of the byte array as it has no precedent. Then, for each element in the array, check if it's greater than the previous one (U8 char maps to ASCII as you expect) and store the result for the next iteration, as well as in an array for viewing overall bumpiness. If the current and prior boolean check are equal, we terminate the loop and it's not bumpy. Else, it's bumpy!

LabVIEW, 33 equivalent bytes

First we convert to lowercase, then to byte array. Trim off the first element of the byte array as it has no precedent. Then, for each element in the array, check if it's greater than the previous one (U8 char maps to ASCII as you expect) and store the result for the next iteration, as well as in an array for viewing overall bumpiness. If the current and prior boolean check are equal, we terminate the loop and it's not bumpy. Else, it's bumpy!