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I recently replaced every electrical component on my crf250r except for the flywheel. However, when I bumpstart the bike it will fire up with no problem and runs fine. Is the flywheel the problem?

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Explain one thing: it only starts with a bumpstart? How did you start the bike before changing every component?  And why did you change those?

So one day I was riding the bike I shut it off went to go start it again then it would not kickstart at all. I then replaced the coil and didn't work, stator and cdi. None made the bike kick start.

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15 minutes ago, mateo_abasllari said:

I then replaced the coil and didn't work, stator and cdi. None made the bike kick start.

Ok age of the piston, how many hours did the piston run so far? How many PSI reveals a Compression test? 

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The whole engine has just been rebuilt. A good 5 hours has been put on it and the compression is in spec. The excited coil is not putting out the 50 volts it needs to.

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this is going to sound dumb.....check your valve clearance.... If the motor was rebuilt and the valves were replaced and not lapped in perfect, they will wear into their seats after a few hours riding.  Once they do, valve lash goes to near zero, making them impossible to kick start but they will bump/roll start.  My crf wouldn't show a spark on the plug when kicking it but it would roll start.  Yeah I scratched my head on that one..... Once I set the valves back into spec, bingo...starts right up.  Something to do with the speed of the flywheel when it hits the compression stroke...strange I know...

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this is going to sound dumb.....check your valve clearance.... If the motor was rebuilt and the valves were replaced and not lapped in perfect, they will wear into their seats after a few hours riding.  Once they do, valve lash goes to near zero, making them impossible to kick start but they will bump/roll start.  My crf wouldn't show a spark on the plug when kicking it but it would roll start.  Yeah I scratched my head on that one..... Once I set the valves back into spec, bingo...starts right up.  Something to do with the speed of the flywheel when it hits the compression stroke...strange I know...

So should I just do a regular valve job?

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On 8/27/2017 at 6:25 PM, mateo_abasllari said:

The whole engine has just been rebuilt. A good 5 hours has been put on it and the compression is in spec.

What is the compression psi?  

If the engine was rebuilt, how come it needs a valve job?  should just need the valves "shimmed" to spec.

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What is the compression psi?  
If the engine was rebuilt, how come it needs a valve job?  should just need the valves "shimmed" to spec.

So I just checked my clearances and my left intake valve was at zero could this be the problem?

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does it roll start? 

Please detail your kick starting procedure.  Every detail, do not skip anything.  These bikes are very picky on how they are kick started.

Mine is:

Cold: gas on, choke on, twist throttle 3 times. Kick engine over slowly 2 times (full kicks all the way down), Then push kick starter down 3rd time slowly till I feel a "thump" and it gets firm. Push slightly more till I feel second "thump".  Then reload kick starter and kick the $hit out of it.  Starts every time.

Hot: Kick once, if it dont start, pull hot start lever-hold it, kick once more...starts every time.

What plug are you using?  If it roll starts does it pop on acceleration or deceleration?

Does it have the factory spark plug boot?  Should be 5000ohms resistance from boot input(unscrew coil wire out of boot) to boot output(where tip of spark plug clicks in).  No more than 5000ohms, no less than 3500ohms.

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