A: Not sure how you can have, both, spark & fuel and still no start. You absolutely have to be missing one of them. You need to go back and verify that the Sportster not getting spark.
Are you getting fuel to your float bowl?
If so, is the float height correct?
Confirm that your needle valve is not hanging up.
Verify that your gas cap is vented. You can be experiencing vapor lock.
Check your fuel line routing. Make sure the line is not collapsing.
Ground your spark plugs and verify that you have strong, definitive spark, both, front and rear.
Check your speedo head for DTC’s.
A failing crank position sensor can cause a problem like yours. A bad sensor will sometimes fail when heat is introduced and begin working again once it cools.
If/when this occurs again, turn off your fuel valve right away to see how much gas is in your float bowl. Open your gas cap and listen for a possible vapor lock condition. Ground your spark plugs to check for spark. If this problem began after you cleaned your carb, start looking in that area 1st.
How to Check and Fix Vapor Lock on a Harley-Davidson