The Japanese firm, which will return to the championship as a factory entrant in 2015, brought two different frames for Randy de Puniet to sample.
As a result of the running it has been able to identify the best configuration, which will now form the basis of future development efforts.
"Today was another good day in our development programme," Brivio said.
"We had a chance to try different tests with various settings and we tried to better understand the bike's behaviour in different conditions.
"Despite difficult weather conditions, we had a chance to choose one of the two frames available, which we will carry on to develop further in future tests.
"In the meantime, our engineers have taken some good information away with them for the next stage of development."
De Puniet, whose running was restricted by rain on Tuesday and by two relatively minor falls on Wednesday, posted a best time of 1m48.600s despite the sub-optimal conditions.
"In this test we were not so lucky with the weather, as yesterday we stayed in the pit all day," de Puniet said.
"Also, the track was slippery and very hot today, so the grip wasn't very good, but we found a good direction with one of the chassis configurations we had available.
"I found one with better tyre contact feeling and better for corner-entry, so we will continue with this in Misano next month.
"The rain came before the end of the test and I couldn't try to improve my lap time, but overall we are very satisfied."
Suzuki will next test at Misano, Italy, on 16-17 September.