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The mark on the case, not the arrow.
 

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Discussion Starter #3
Is it possible that the bike could have timing issues still if everything matches up? Piston is at tdc, T mark in the window, slack on the valves cam Mark's line up with the casting point. New piston and valves all the bike does is backfire while cranking.
 

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Does it have good spark at the plug? Have you tried a different spark plug?
 

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Discussion Starter #5
Yea solid blue spark, it will spark as long as you hold the start button sparks with pullstart too. The bike didnt run before I replaced the piston and valves. Compression test on cold (40) degree motor is 87psi which is within spec 78-121. Every once and a while it will idle for maybe 2 seconds but sounds very low like 250rpm or so. Before piston it wouldn't even backfire now it does.
 

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Discussion Starter #6
Yea solid blue spark, it will spark as long as you hold the start button sparks with pullstart too. The bike didnt run before I replaced the piston and valves. Compression test on cold (40) degree motor is 87psi which is within spec 78-121. Every once and a while it will idle for maybe 2 seconds but sounds very low like 250rpm or so. Before piston it wouldn't even backfire now it does.
When with ether or gas down the plug hole I get nothing. I've got compression fuel and spark but no ignition so it seems like possibly plug is firing at incorrect time.
 

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The icm controls that signal from the pick up coil. The chain mark is the valve timing which looks correct. There is a very slim chance that the key sheared on the flywheel changing the timing some. That should be noticable when lining up all the.marks and putting the piston at tdc. I would make sure the carb is good and clean to make sure it's not a fuel problem.
 

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Discussion Starter #8
I've cleaned all jets and passages with cleaner and then blew out with compressed air, the plug does come out wet after cranking for awhile. Also if you crank when the plug is out it shoots a mist of air/fuel out of the hole. I rebuilt it with an ebay kit I'm wondering if maybe I should try and go back to the origional jets. Could it be a cdi issue, I know most people say they either work or dont but I'm at a loss at this point for why it wont start. I bought the cdi used and it's a Phillip's marked HM7 so I know it is oem. I wish I could post a video on here so you could hear it
 

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With that much fuel i would go back to the carb first. Either the float is sticking allowing too much fuel or the jets are too large.
 

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Discussion Starter #10
I'm going to clean up the oem ones and give them a whirl tonight. Any comment on possible cdi issue? Could too much fuel also cause some to be blown back out the carb from time to time?
 

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Most if the time the cdi is good or it isn't but anything is possible. The early 450 was good.for wearing the body where the float pin sits which would cause them to get too much fuel.
 

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Discussion Starter #12
Yea mine is a 1997 400, but I did notice that it would leak fuel from time to time out of the overflow. I know the seat is not removable so I figured that the new one would fix it. It helped but not perfect. And yes it's strange the needle just rests in bbn plastic. I'm used to floats that mount to something and can be bent to adjust float height.
 

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I would try a brand new spark plug just to eliminate the possibility
I’ve had quite a few weird spark plugs issues while they showed a nice blue spark, they were actually jumping the spark from the base of the spark plug to the motor while I was testing them and the spark was not actually jumping the gap properly while installed

sometimes ATV would idle for a few seconds and die other times it would backfire
I replaced the spark plug and ran like new
It’s an easy thing to try just to make sure


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