Don't give up yet. I had to really play around with mine to get it right.
Try playing a bit more with the accelerator pump.
If I recall on my 250 my jets are a 49, squirter is a 25, and I have a orange accelerator cam. Yours will likely be different but it should get you in the ballpark.
The pump arm should have no gap at all when at idle and should have some tension in fact. That's what caused my bog. Well that and a vacuum leak.
