Newbie with posible low no oil prime issue

Just rebuilt a non running 2005 crf100f. Bored .020 new piston and rings and valve job. The old piston had scaring on the sides but the cylinder was smooth. The piston wrist pin had a fair amount of scaring damage and was a bear to get out. Suspected low to no oil caused the problems. So apon reassembly was leary and made sure cylinder and head oil passages were all clear. The bike starts on first kick let it warm up for 4 mins and crack open the oil check bolt maybe a drop comes out run another 2 mins nothing. Yes there is a quart of oil in it. Scared to run it any longer. I assume a fair amount of oil should come out of the oil check bolt right. Anyway to manually prime the oil system? Anyway to check for blockage from the oil pump to the cylinder. I'm good from cylinder to top. I paid attention to gaskets and feel they are on correctly and not blocking oil passages. Looks like no way to test the oil pump. Help

Did you rebuild the bottom end? The oil passages are connected to the bottom end. Smooth cylinder and scored piston. I wonder what your clearances were. What was the big end bearing like? No way that I know of to prime. Sounds like something is still blocked.

I did not rebuild the bottom end crank bearing seemed fine no slop or play rotated smoothly. I think I will blow some compressed air into the oil check bolt and see if I can hear it through the oil fill hole. don't see how this can harm anything. Probably will just flow to least resistance like across cam and down timing chain shaft. Looks like cover coming back off.

Problem Solved!!!!! Replaced the oil pump with a new unit Bingo oil flowing within a couple seconds. Sure glad I listened to my gutt and not run the bike any longer till I was sure oil flowed.

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