Li150 Strange Starting Issue - Vaccuum Fuel Seal? Compression Seal?

[B-Race Tuning]

I'm sorry kurtminus, I can't resist it....
"So I am curious what’s the best thing to do when going down a steep long hill" ??
Utilise gravity and use WOT!

I only use NGK on my engine builds and recommend them. I have used some Nippons but VERY rarely (short reach in modified casa SS250) and more an availability over choice.

Are you any further forward.