Thank you in advance for reading this and any suggestions you may have. I've been riding and working on two strokes for 15 years and decided to give 4 strokes a try. I bought a 2009 yz450f with a blown top end and have rebuilt the engine but cannot get the bike to start. I will describe what I have done and the symptoms below. I split the cases and went through the entire motor, checking specs, cleaning and lubing and re-torquing everything. For the top end I bought a new OEM cylinder, piston, rings, bearings, gaskets, timing chain, tensioner and guides. I bought a used OEM head with valves from a friends whose bike ran great and sold the head because he put on a GYTR head. I disassembled the head and measured the specs on the valves and springs, all were in spec and were put back in. I used the cams from the blown head as they appeared to be in better shape. I have checked and rechecked all of the valve clearances, all intake are 0.13mm - 0.14mm and exhaust 0.22-0.23mm, I also disassembled the carb, sprayed cleaner through all passages and replace all jets with oem sizes. Bike is all stock with a new air filter and spark plug (I've tried multiple plugs). When I attempt to start the bike the engine feels "tight" (too much compression?) when I kick it. If I remove the plug everything moves smoothly as would be expected. I've kicked the bike hundreds of times, primarily following the manual guidelines (no throttle, choke on, gas on) but have also tried every conceivable combination of throttle, pet-cock, choke and hot start. Out of those hundreds of kicks it has backfired 3 times. I also tried to bump start it three times, the first two it attempted to run(1-2 seconds) and immediately shut off, the third time it did nothing. I have pulled the spark plug and I am getting a good crisp blue spark each time I kick. The plug is also appropriately wet and hence I believe the issue is not in the carb. At one point I even put a water bottle cap full of gas in the cylinder and tried kicking it, no difference. I have also checked that the flywheel is properly keyed and that TDC is actually TDC using a straw. I've read dozens of posts on the forum about this and related problems, it sounds like a timing issue but all my marks are almost perfectly aligned and I have "13 pins" between the "12 oclock" cam punches. Before I move them 1 tooth in either direction to see what happens I wanted to get so input from you guys. It sounds like I have the cams advanced 1 tooth from reading forums but I don't know which direction that actually is? I have attached pictures of my current timing; any help would be appreciated greatly!