Start with a plug change and throttle body sync. Might smooth it out and cool it down.
Done all that. Checked starter valve balance several times. Including last time with calibrated gauges.
Spent hours trying propane enrichment
Check map and throttle position sensors
Cleaned and flow tested injectors replaced all vacuum tubes and tees
Made fitting for end of fuel rail and checked fuel pressure.
Everything is bang on spec.
Was told fuel pressure can be ok but flow is not enough and was engineering a way to test that when I read about the o2 sensors and how they affect fuel mapping.
According to some "experts" they are extremely prone to failure and the kilometers on my bike are in the sweet spot for sensor fsilure.
They can even give the appearance of working ok but apparently their response time can be out of wack and even this can cause leaning out.
I know i am clutching at straws but i have tried everything i know and had it a three different mechanics with no solution yet.
Will know for sure when my you beaut chinese o2 sensor turns up.
If I am right you will hear the cheer all the way over in the US!! If not wanna buy a cheap ST1300. Only ridden by a little old lady to church on Sundays.
Promise!