plug fouling problem unsolved

[fabulous furry]

I had a rich bottom end and doing searches I came across the solutions below. The slide change worked for me, cleaned up the whole bottom end, couldn't even get it to idle for very long with a 35 pilot and air screw nearly 4 turns outs. With an 8 slide I had to increase to a 38 pilot and have the air screw at +/- 1-1/4 turns out, idles all day long

i know it was a bit silly to try a 5 plug but in search of a solution..it did not even rev properly anyway.the slide is probably the last thing i did not try. the mix is good the octane is ok since i add octane booster and the base gasket is a standard .25 mm.
in the caribbean it is not easy to machine the cylinder head but i don't think it is that bad for a new bike my 250 had the original plug for 5 years and works like a champ.