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cobbled together special.. help with tuning a rm250 2 stroke mikuni TM on a DR370 4 stroke

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So I have this old rat bike, 78 Suzuki dr370 its got good compression,  it came with the original EI / lectron carb disassembled in a box,  not knowing a thing about these carbs, I bought a mikuni of a rm250 as it was the same size and cheap.  anyways as it came off the rm and installed on the DR it was running stupid rich..   not surprising as Suzuki knows how to build a snarly 2 stroke,  it had a 310 main jet in it,  biggest ive seen lol,  so I went way down to a 160,  that got it running as it should at higher rpms, but its now loading up at idle and low rpm's,  it was starting to load up yesterday in the driveway, so I goosed the throttle to try and clear it out,  but instead it coughed out the intake a nice fuel vapor mixture and died.  When trying to re start it, it kicked back so hard that it broke the kick start lever.  did some research and found that a leaky choke plunger can cause this,  then I got to thinking that maybe the pilot jet might need to be downsized as well,  I am getting into territory I am not familiar with.  what rpm range does the pilot jet affect?  I've never had to mess with that jet, usually just clean it and reinstall when I am working with carbs. would that need to be brought down?

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