The Spanish rider ended the first day of practice at Sepang with a narrow advantage of less than a tenth of a second over Marc Marquez after posting the quickest time in FP2.
It came a day after one of his two GSX-RR bikes was engulfed by flames in the pits, but it did not suffer major damage.
"They did a really big job [to prepare the bike]," said Rins.
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"Yesterday when the bike set on fire, I was [behind the garage] doing something, and when I went into the box, I saw everybody with water - I couldn't understand anything.
The funny thing is the laptime I did today, I did with this bike - the fire one. I was scared because Marco [Rosa Gastaldo], my mechanic was on the bike and he [faced] all the fire. But he is ok, so this is the important thing.
Rins clarified that his Suzuki had not needed to have any major components changed as a result of the fire.
"We changed the electronic cables - but the fairing, chassis, engine are the same," he said.
"In FP1 we used the other bike, in FP2 we went with this bike, because on the 'flames' bike, we had the electronic area a little bit different - a different map that we tried and it was good."
Rins highlighted braking as an area where Suzuki can make up ground, but was otherwise satisfied with his practice form.
"I'm very happy because we worked good from the beginning of FP1," said Rins.
"Still, we need to improve because for sure [the other riders] will improve their laptimes.
"We need to work a little bit on the braking area, because compared to the test we are losing a little bit on this area. But for the rest it was very good."
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