Binder, who was chosen for the works KTM ride vacated by Johann Zarco for 2020, concluded the Qatar test ninth-fastest as the Austrian marque's top representative.
With a best laptime only 0.425s slower than pace-setter Maverick Vinales, the South African bested teammate Pol Espargaro by three tenths.
Despite his impressive one-lap pace, Binder admitted that he still needs to work on his race pace ahead of the season opener at the track on March 9.
"We made a change and the bike got way better," he said. "It felt more comfortable to get the bike stopped and also to get it turned quickly and on the throttle earlier. Once we figured that out, it was easier to put a fast lap together.
"I put on a set of new tyres. I didn’t really expect it. I came across the line and was like, ‘jeez’. But it’s one thing to do a fast lap and it’s another thing to do 22 of them.
"Race distance is hard on this bike; on the MotoGP bike generally it’s a different story. The tyres drop, it starts to spin a lot more, when you lose the fuel how different the bike is crazy. I’ve a lot to learn and very quickly."
Brad Binder, Red Bull KTM Factory Racing
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