Mainly the first one, high idle when hot although it isn't consistent, in that it doesn't always do it. I've bought the thick gasket to insulate the throttle bodies from heat and I'm going to have a look at the idle control valve and will also try the suggestion about blocking off the IAC pipe. I was interested in the throttle body calibration as at one point the factory told me I would need new throttle bodies due to the idle screw being adjusted. I found out from SC that this wasn't necessary as SC had provided Norton with instructions for setting the idle screw using their software, which is something else I will be doing. The factory had at least 3 attempts at fixing the tickover issue while it was in warranty although all they did was change the mapping and adjust the TPS - although I could never find out what map they had actually used. I know now as I have the SC software, and it's on the right map for the short pipes. In the end I determined that they weren't going to fix it, as each time they said it was fixed and it wasn't, and it was costing me £200 to ship it to them. To be fair to current folks, the technical staff I was dealing with are no longer there. Although I'm not as mechanically inclined as others on this forum I find it helps to understand a problem even if you don't end up fixing it yourself, hence the question about the calibration. Could the butterfly adjustment be checked using a vacuum gauge, I'm assuming this is how carbs would be synchronised?