Hi Nick, it may be that your bike has not been used much recently and the flow of fuel has increased as the jets and passageways have had any crud moved along. Mine has only done 10000 miles and I had the same experience, requiring some resetting as the miles were accumulated. I suggest you wind out the throttle stop screw adjusted on the carburettor body. It’s the screw at 60 degrees pointing up to the slider, in and the idle will increase, out and it will reduce. The horizontal screw close by is the slow running mixture, so best leave that as is.
I think you may be spot on- I have had to drill the the fuel tap as it had white residue restricting flow. I felt this could be from the inside of the aluminium tank?
Ticking over well now!
On checking the slow running screw it was nearly full in - less than a quarter turn out. I have increased this to 3/4 turnout and its much improved. What setting are other owners set at - I don't want to over do it, in case it made the mixture too weak?
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