Factory sealed throttle body pack.
My 98 KRS engine developed rough running characteristics at around 12K miles. The idle through 4k rpm were affected. In short, idle to highway speed where engine roughness seemed to smoothed out. My suspicion is that it wasn't smoothing out as much as it was concealed.
The problem was so irritating that I sold the bike unable find a solution. Three shops told me to ignore the problem since it wasn't there. The last shop wanted to switch out the throttle body pack for a new one, but would not gaurantee the problem would go away. All agreed that the throttle bodies were pre set at the factory and that there was no way to adjust them properly without factory equipment. Being made of plastic may not have helped. Being sealed, made it a throw away setup, if it went bad.
I bought a Rhine chip hoping that would correct the problem. It didn't. In all, I probably spent about $2,500 more trying to correct the problem.
Before you go any further, make sure to have a leak down pressure test done. I loved my 98 KRS, but the problem finaly drove me to the ultimate solution. Any body else has or had this problem?