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KX250F Popping/Backfiring

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Ok so I recently bought a used 2008 KX250F for 1900 bucks. When I bought it, it had 213 hours on the hour meter and I've gotten almost 9 hours on it so far. Everything had been rebuilt for the previous owner of the bike when he got it, he was the second owner and never had any problems with it. The owner told me to get the valves checked after I'd purchased it because it was popping a little bit. I did so and they were all in spec. It still had this same popping and the mechanic at the shop I took it to said to get the carb cleaned as that was probably the cause.

So I took the bowl off the carb and it was clean and changed the Main Jet and Pilot Jet in it. It had a 42 Pilot and a 178 Main, that I changed to a 190 Main and a new 42 Pilot. After changing the jets it had alot more power, but still had a slight popping to it at idle. This was about 2 months ago when the weather was still in the 70's-80's.

Now It's in the 50's here and on certain days the bike doesn't seem to pop as much but today it was popping like crazy after I rode it and had been the worse it's ever been. I changed the Main to a 195 because it's only going to be getting colder out and left the Pilot at a 42. After riding it today the bike seems to pop like crazy whenever i give it gas at idle and when I'm riding it.

The idle also gets extremely high after I pin it and then come to a stop, so I adjust it so it isn't screaming as high. I find myself constantly doing this.

So can anyone help me out with what I should do to stop the popping? I'm thinking about going up to a 45 Pilot... ? Any help or tips are appreciated, thank you

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