These KTMs have been a stalwart of ours for the last few years – we’ve ECU remapped nearly 500 V-twins! And maybe 300 of those were SMTs. Most we can sort properly, but the odd one is a horror show; KTM’s later mapping is better, but the early ones weren’t good.
We also find that with age and servicing the throttle bodies go out of balance, and we see problems regularly with older bikes. We have to square them before the remap, because it’s impossible to cure the jerky/switchy low speed running otherwise. But, once balanced, and with the fuelling and ignition tables trimmed (plus the emissions nonsense switched off) it’s like having a good set of carbs bolted on! Smooth as silk.