I'd forgotten that the later ST3 used Lambda sensor and a closed loop system. This is for emissions reasons using them to keep the fuel air ratio as near to the 'optimum' as possible. It has the effect of making the bike run on the lean side and can create a tendency to surge and snatch at small throttle openings and it's not just the ST3 that's affected, nearly all Ducatis and presumably other bikes so fitted are susceptible to this problem. It has nothing to do with the CAN bus. There are ways to subvert the Lambda sensors and make the bike nicer to ride though.
No doubt there are Derek, and the cousins on the other side of the pond seem to have it well sussed. I'm just pointing out that this could be Archer17 's problem with "on/off" uneveness at low speeds.
Thanks for this help guys. The problem has been reduced considerably since I had the bike serviced by Carl Harrison in Harleston this summer! I don't know what he did but it's much better now and certainly bearable, but I might have to see if the lambda sensor could be partly to blame.
