4 Stroke Engine will not Start!!

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I read on a karting site the intake is .005" exhaust .007", and 60 to 80 is normal on a stock engine. It will probably come up some once the rings seat. Also while doing a compression test the throttle needs to be wide open.
I set my intake to 6/1000 and exhaust 8/1000 but I made them extra tight so they are closer to 5 and 7 and a half.
The compression test was performed with the valve cover off and the throttle closed. Do u really think it makes a huge difference with wide open. Maybe small, because when starting an engine the choke is on....
 
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I set my intake to 6/1000 and exhaust 8/1000 but I made them extra tight so they are closer to 5 and 7 and a half.
The compression test was performed with the valve cover off and the throttle closed. Do u really think it makes a huge difference with wide open. Maybe small, because when starting an engine the choke is on....
It's just the age old suggested method with the throttle wide open. Your compressing atmosphere and atomized fuel so the more of it you let in the more their is to compress. Checking compression has nothing to do with starting. Your drawing in as much fuel and air as you can without the engine running to get your max. number. Honestly though I haven't a clue as to how much diff. it makes. Something I'll have to look into so next time someone asks I'll know.
 
After thinking about it a little more I guess through the exhaust you would still be getting enough air on a 2 stroke so the only diff. would be the fuel to air ratio. Probably more important on a 4 stroke. Still the fuel would make a diff. because of the old liquid being harder to compress thing.
 
Turns out I just tried starting it now and it won’t work. I believe I sheared a flywheel key when trying to start the engine with a drill. What do I do....
 
If you put that plug back in your going to need to vent your tank as well, i can't believe no one mentioned that...
Actually didn’t shear the key. It was a guess as the engine when pulled created a little explosion sound and died. And a google search seemed to confirm that as a sheared key. Turns out that it wasn’t sheared but damaged and perhaps the flywheel was then i installed in the wrong place out of timing. Therefore just installed back in timing spot and I’ll test it out soon.
 
Actually didn’t shear the key. It was a guess as the engine when pulled created a little explosion sound and died. And a google search seemed to confirm that as a sheared key. Turns out that it wasn’t sheared but damaged and perhaps the flywheel was then i installed in the wrong place out of timing. Therefore just installed back in timing spot and I’ll test it out soon.
Frogslayer's got a point. If the tank isn't vented even if you do get it to start it's not gonna run long.
 
Frogslayer's got a point. If the tank isn't vented even if you do get it to start it's not gonna run long.
you mean the water bottle. yeah the air vent on the gas tank broke when i dropped the engine like 3 months ago, so yesterday rather than fix it, i decided to make a new gas tank from a water bottle; it has 1.3 liters (1/3 gal) so that should give me like 30 to 50 miles or so. i took a check valve from a fish tank and drilled a hole in the cap such that air can flow from the atmosphere into the bottle yet air (and perhaps gas too) cant flow from the bottle into the atmosphere. https://motoredbikes.com/threads/3d-printed-fuel-tank.55010/#lg=thread-55010&slide=0
 
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