I've got one for ya'll. Got my stock 1994 KX500 12yrs ago, rode it hard since, lots of WOT, perfect jetting. No fouled plugs ever. Michigan Elevation ~1100ft.
I believe this was:
60 pilot, 1.5 turns out on the screw
168 main (since this single jet I found in my "KX500" bucket)
stock needle (for 1994 is N82R), center clip
#7 slide
Now ~3yr ago I changed the stock pipe to a FMF Gnarly, and followed whatever they recommended for main jet which was a 175 which I picked up at my local bike shop... HOWEVER... ever since, the top end feels like it falls off, and to me it feels lean at WOT. I took the carb apart today and found a "175RD" main... which I have come to learn is not an OEM jet... it's actually from here: http://ebcbrakes.com/product/main-jets-for-carburettors/
So anybody have any idea if that jet is leaner or the same as a real Keihin 175? If I put my stock 168 jet back in there... do you think that is OK with the FMF pipe? FMF recommends 175 and a 58 pilot (I have 60 pilot).
I'd say right now, it feels perfect to maybe just a bit lean from 1/4-3/4 throttle, then WOT, mid to higher RPM in my opinion seems weaker than it should... (lean).
Thanks for any suggestions!!!