timing help

ok i have a 2002 xr650l motor in a 400ex frame when i got it second gear was bad so i pulled it all apart and i put new gears in it and bored it and put a je10.25:1 102mm piston in it. it also has a stage 1 hot cam now i have everything back together and i have spark and fuel but it wont start so it has to be my timing but this is my first 4 stroke i have ever worked on and im teaching myself as i go and i dont have a manual so ive done good doing everything but the timing i have no idea what to do. i put the piston at tdc of what i believe was the compression stroke and the put the cam in with the lobes facing down and the three marks on the gear facing left and right and up. i belive this is correct please help me out

You've obviously checked the valve timing by removing the Tappet covers and getting the old Feeler gauge in there.If you have had it to bits they will need redoing..Slightly loose is better than to tight..The general procedure for that is to pull the plug..Rotate the engine using a Socket on the I believe 17mm bolt on the crank down where the timing marks are.Turn the engine in an anti-clockwise direction and get a Screwdriver/Chopstick and pop it in the spark plug hole..When the pistons all the way up to the top of the cylinder and the T mark lines up down the bottom both inlet and exhaust tappets should be slightly loose..adjust them now..if one sets loose and ones tight you are not on the compression stroke.In that case rotate the engine all the way around again stopping at the T mark and try them again for looseness.Course if the tappet covers off and every things lined up with the marks and the cam lobes are down and the marks on the cam sprocket are lined up and the pistons at the top of the stroke..whip the cover on and adjust them.

And I believe the gaps for the Tappets are Intake.. 0.10mm or 0.004in

Exhaust 0.12mm or 0.005in Thats for a 92 xr600,,someone correct them if their wrong as their from the most modern manual I have.

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