Jonnierw

I don't know for sure the amount of oil in the airbox but when it was fixed before they said there was a fair amount and the filter was soaked.

The oil level window still says I have a good level of oil in the engine so I don't think it needs topping-up.

K3 is first model with fuel injection. Injection system could be a problem, but wouldn't that appear soon after starting the bike even if its running lean?
Also on slowing down after the run the bike was back-firing very loudly.

Bike is stock, no mods at all, apart from crash bungs, Givi rack and top-box and alarm.

The restrictiong was done by putting restriction rings in the fuel/air line and a throttle twist-stop on the throttle.

I will look into the compression test.

Thanks for all the advice.