I can't comment on the Toyota/Honda figures but my old Daytona was only 10 Nm (7.4 lbft) and I think the 675 and Thruxton motors are the same. 20 Nm still seems a lot to me.
I must say, with your fuelling issues as well, it does seem that the biking gods have taken against you recently! Have you run over a black cat or something??