Motorcycle Repair: HONDA NX650 DOMINATOR idle problem, honda nx650, crisp throttle response

Question
Hello Mark.
I'm an owner of a HONDA NX 650X DOMINETOR(2000).
The modifications I made:
Air filter replased with a K&N one and
I changed the spark plug with an NGK DPR8EVX-9.
The idle speed is set at 1300-1400 rpms but after
15 minets of riding idle rises up to 1600-1700
rpms and after high speed riding idle stols and
engine turns off.The air screw is set 3 turns out.
Any suggestions?
Thanks for your time.
John Psimopoulos

Answer
Hi John,

Try adjusting the idle speed down to about 1000 with air-fuel scrwew set at 1.5 turns out. Adjust a/f screw to get crisp throttle response when blipping throttle at idle.

I suspect an intake air leak may be present causing the higher idle after riding. I need to know the conditon of spark plug to (appearance) and cylinder compression, if possible. Also need email address to return info files if necessary.

Respectfully,
Mark Shively