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Discussion Starter #1
originally had my griz600 stop running and then wouldn’t start ! After testing all coils , valve lash , compression (115psi) and all tested ok I bought a used cdi . After cdi install it still wouldn’t start (no spark) ! So even though the stator , pulse/trigger and charge coils check within good range I decided to switch the stator etc ! It started but It is very unresponsive on throttle and acts like it is running in 2 Different spark timing ! Since I replaced the stator and it started I then decided to install the cdi I replaced and it did the same thing ! Also I noticed the Used cdi I Took off had a capacitor that had swelled and extruded from the back of the cdi . I had always heard and I believed that when these CDIs go bad they machine will quit and will not run . Is that true ? I also checked the cam/valve timing and its ok ! Checked with timing light and it does fluctuate on idle ! I am thinking I have 2 bad CDIs . I also switched the trigger Coil wires and would not start then . Man , this thing ran good before and I am confused !
 

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Hum...this is a tough one, so thinking.......
Generally electrical components work or don't and are not intermittent, and as it starts its hard to suspect the battery for low voltage/amps and the plug is firing hot enough to start and run. But a weak cell can be the problem causing the electric system to be on the verge of not enough power.
Or maybe a ground connection is dirty or corroded for the problem.
Is is backfiring through the exhaust?
 

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Discussion Starter #3
New battery although that should not matter since it gets the charge power from the charge coil . The stator I removed ohms were good , i had installed it a couple yrs ago and I was surprised that it ohmd ok but started after replacing it ! To me it seems like spark condition but I am going to remove carb and check it over . I considered a ground also but have looked wiring over well .
 

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Then if it has constant hot power, enough of that.
A varying timing input at idle is a big problem, its like the crank shaft is not tight with the cam....a loose chain? worn gears?
Not to test your mechanical skills, when checking the valve lash did you happen to rock the crank back and forth to look for piston movement without the cam moving? Slack in the chain can cause variable valve lash and weak performance, that's why I ask if its backfiring through the intake. Thinking about two firing positions........the position sensor would have to be loose, but how? Its like you have two different problems.
 

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Discussion Starter #5
Then if it has constant hot power, enough of that.
A varying timing input at idle is a big problem, its like the crank shaft is not tight with the cam....a loose chain? worn gears?
Not to test your mechanical skills, when checking the valve lash did you happen to rock the crank back and forth to look for piston movement without the cam moving? Slack in the chain can cause variable valve lash and weak performance, that's why I ask if its backfiring through the intake. Thinking about two firing positions........the position sensor would have to be loose, but how? Its like you have two different problems.
Then if it has constant hot power, enough of that.
A varying timing input at idle is a big problem, its like the crank shaft is not tight with the cam....a loose chain? worn gears?
Not to test your mechanical skills, when checking the valve lash did you happen to rock the crank back and forth to look for piston movement without the cam moving? Slack in the chain can cause variable valve lash and weak performance, that's why I ask if its backfiring through the intake. Thinking about two firing positions........the position sensor would have to be loose, but how? Its like you have two different problems.
Well took carb off and everything looked great on it ! Put back on and started but same misfiring . It did a big backfire and quit and wouldn’t start ! Put a sparkplug on plug wire and has good spark when cranked over so it could have jumped timing . Going to tear it down and check cam timing and everything . Things like this become a challenge
 

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Look for a bad timing chain as you tear down.
 

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Discussion Starter #7
Got it tore down , engine is very good condition , no ridge in cylinder , cam very good , timing chain wore . Before I tore it apart I set to tdc and cam dots were not where they should of been . I tried moving a tooth and either way I went the dots wouldn’t line up correctly ! So order T chain , rings and gaskets and will do a quick cleanup hone and check valves before assembly .
 

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Discussion Starter #9
Well all back together and started ok but ran like crap still ! Took cdi off and it fried it just like the other one I had on it ! Is there anything that could be frying the CDIs ! In pics you can see where a capacitor bubbled and melted whatever the stuff is ! The other pic is the 1st cdi and it bubbled same as the latest one ! I spent hrs digging the stuff out to see what size the capacitor was but wrap on cap melted when using acetone ! I think I’m going to try the Chinese 6 wire cdi ! These Grizzly600 CDIs are very expensive !
98702
98703
 

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I bet you have a short, and another part will do the same thing.
Ohm's :)
Check the wiring from each end to find the break.
 

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What causes the starter to hang up on these engines ?
Multiple things can:
Weak battery.
Bad/worn starter motor (worn brushes or magnets de-bonded from casing).
Bad solenoid.
Bad or dirty connections on battery, solenoid, starter motor, chassis ground.
Broken/failed auto decompression system.
 

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Discussion Starter #14
Bendix is my thought because all you mentioned is new or correct ! I should have ask what makes the bendix hang up .
 

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Bendix is my thought because all you mentioned is new or correct ! I should have ask what makes the bendix hang up .
What makes the bendix hang and keep turning the starter motor once the engine starts is simply wear. Bendix drives wear out, like any other mechanical part. Additionally, there is usually a spring in them that can become weak or broken, and this can cause them to hang up.
 

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Discussion Starter #16
Yes Sir the spring is weak , I will be replacing soon ! Also I didn’t observe it but see people mentioning a sprag on the bendix that could be bad . Maybe not on the 600 model .Thanks
 
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