Just thought I'd finish this off.
Chain adjusted and clutch cable adjusted to within an inch of his life, only two missed second gears; one corrected by clutch cable.
That could be a fluke and it might just be chain adjusted, but in the million bikes I've had, I've never come across this.
My chain wasn't loose......... it was probably around 30 to 40mm as opposed to 25 to 30. Some say that 25 to 30 is too tight.
I ensured that it didn't become a guitar string after setting by putting my weight on it.
I'm sure this bike is critical to cable adjustment too. I had it at about 4 or 5mm; don't normally bust a gut about that, but Ari really needs the book's 2 to 3 mm.
Anyway, all good now.