I'm running the Kstar 50cc with 15mm dellorto & 70 jet. 72 jet and I four stroke a bit. I had the techno boss pipe on there but just switch to a biturbo. hitting 45+
You might be restricting too much air with the stock dellorto filter. Remove it and see if it'll start. I too run the stock filter, but I removed most of the screens from it.