Welcome to the forum Jon D.
Seems like you've been quite effective in looking after the F2, tested over substantial period too
I've always liked the F2, very good to ride and good looking.
The PD cards, I can obviously see there's strong opinions
about them, but do think they are an excellent design in carburation terms. They run more optimum non load mixture (rather than excess) with attendant benefits in more complete combustion, supplemented by the pump to stoke it when needed for acceleration. In reality, metering close towards fuel injection system in their accuracy. A very good technical design.
Which colour F2 is it ?