This thing is making me crazy. My 912 ul will run very rough after start up from idle to about 3000rpm. Above 3000 is smooths out and runs fine at higher rpms. Here is wher it gets strange, after I fly for a while is will idle smoothly but still has some roughness about 2800 rpm but much better than at start up. I've had the cabs off several time checking and cleaning everything, float arm height, tips, needle jets etc. and balanced the carbs several times. They show even balance (with both a Carbmate and guages) at 2500 rpm but it stillruns rough. It's almost like there is a fouled plug that clears itself after it heats up but I can't detect anything when I pull the plugs. It runs the same on either ignition box. I'm thinking it is somewhere in the carburation due to it partially clearing itself up when warm, but I running out of ideas where to look next. Any suggestions ?
Thanks
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