Hi Jan,
I’m no expert on the Scott engine unlike previous contributors. I have a number of old bikes and a 49 Flyer is just one. I have followed your posts over a period of time and you seem pretty knowledgable on Scott’s. I would however just add a couple of points that can easily be over looked.
Is water flowing through the radiator satisfactorily, ie is it sufficient at higher speeds. The general mistake with 2 strokes is to add more oil to the petrol when seizures take place. This can be counter productive as it weakens the petrol / air mixture as a proportion of the petrol is taken up by the oil. For this reason Roger’s suggestion of altering the needle height seems a good starting point. Best of luck & let us know of your progress.
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