Uhu - My Bullets seem to take maybe 10-15 seconds to pump up scavenged oil in normal use.
Did you leave a cup or so in the crankcase for the scavenge pump to grab onto before you put on the top end? The crankcase vent is one access point to inject some oil into the crankcase post-assembly. Have you popped off the crankcase drain plug to verify rod bearing oil is actually making it in there? That will verify the crank is getting oil.
After three minutes of run time, there should definitely be oil in the crankcase. If NO oil in the crankcase, try squirting oil into the crank stub with the crankcase drain plug out to verify that that vital passage is indeed working. A bit of cork or swarf can be a showstopper. If this passage is plugged, I'd try a "Mity-Vac" or some such fluid sucker to try to pull it back out. Who knows, it might work...
If there
is oil in the crankcase but but still no scavenge flow, it's probably time to pop off the timing cover.
Verify the suction side passage to the scavenge pump from the crankcase casting is clear. Manually squirt oil thru the suction passage back to the case sump with the drain plug out and check for flow.
If the scavenge suction side intake passage is clear, manually turn the spindle to verify pumping action. Oil supplied to the scavenge suction port will be pumped out the discharge port.
If the scavenge pump functions manually, check the cover gasket to verify it isn't blocking suction or discharge flow to the engine case casting.
If that all works, manually squirt oil up thru the case scavenge discharge side oil passages to see if it gets to the external line connection.
If that's good, make certain the "Y" external oil line is clear on both sides.
Reassemble, add a cup of oil to the crankcase, use an external fuel tank, pop off the tappet covers like the Indians do and verify flow out of the rockers when the engine is running with the fuel tank off.
Be methodical and don't assume anything. This is simple stuff, but a blocked oil passage or scuffed up pump innards can make everything "grind" to a halt.
Let us all know how this turns out. Pictures are always welcome and helpful.
Good Hunting - ACR -