As mentioned in earlier posts, the root cause of the bike’s poor running at the Ryedale turns out to have been the TPS.
Research suggests that if it gets a good soaking, that it can short between two of the pins frying the internals, so it’s not just a case of waiting for it to dry out. It also reports the manifold intake pressure and temperatures and was reporting the intake to be at in excess of 150 deg C with the engine cold and not running.
I replaced the TPS with one from the spare bike and all was well.
I called Huskysport today to be told that the TPS isn’t a replaceable part, and I’d have to order an entire throttlebody at £467!
I’m now doing some digging to find out what the manufacturer and maybe part number of the TPS unit itself is so I can source an alternative. It’s a Mikuni 45mm throttle body, but I’ve not found anything remotely similar yet. :S
Still, at least I know the fault, and cause, and can try to mitigate against it happening again until I have a suitable spare.
Update: I’ve identified the sensor. More here in my Mikuni MAQS post