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Discussion Starter · #1 ·
So I checked the timing on my sled today. 93 xcr 440, fuji motor.
this is where it was( those are the marks on the flywheel)

__
__ -- right here is where it is at.
__
__
__


_____




Does anyone know where the base timing should be set at?
 

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should be set at zero. (the long line)
 

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Discussion Starter · #3 ·
dam no wonder why its not running right!!

just to be sure, this was done with a timing light with it idling.
 

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Neither of the above posts are correct. The timing "position" has to be determined by rotating the engine counterclockwise until the Mag piston is .250" BTDC this point should be marked on the flywheel between the two little arrows on the hole in the case. Then rotated in the normal direction "the specified amount for the engine you are working on" very important. There is even a difference from a Fuji 440 and 500 . A 440 I believe is .173. In between these measurments is your safe zone, not "the middle line". Timing also has to be varified at 3000RPM not idle.
 

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Discussion Starter · #5 ·
So those marks on the flywheel don't really mean anything? I need to get a dial gauge and mark on the flywheel at 0.250" than another at 0.173? and set it somewhere between there at 3k rpm? Can anyone confirm that number?
 

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skiroulertx447 said:
So those marks on the flywheel don't really mean anything? I need to get a dial gauge and mark on the flywheel at 0.250" than another at 0.173? and set it somewhere between there at 3k rpm? Can anyone confirm that number?
Dial indicator has to be on the mag piston. Sorry, should have mentioned that. You'll find that the lines do end up in play. Just not always the middle one. I've got my manual at the shop, I can confirm the spec later for you.
 

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Discussion Starter · #7 ·
Thanks for the info, I'll talk to the dealer tomorrow some more to try and get them to tell me the timing specs also, hopefully there open. Or if you get them from your manual that would work to.
 

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I checked, it is .172. So set it at TDC on the mag side rotate the engine .250" (two and a half rotations on the dial indicator) BTDC (in the opposite rotation of normal) and mark the flywheel in the hole between the case arrows (it should line up with one of the lines). Then rotate the engine in the normal dirreection .173". Run the engine at 3000 rpm and make sure you're between those lines and you won't have a kaboom. If it's off you have to rotate the stator in which ever way is required.
 

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Discussion Starter · #9 ·
Thanks, I'll figure it out!! I had ridden it all last year without problems so it can't be too far off. The stator plate is off my motor that blew up and I tried to get it back to the spot it was on the other motor. Now if I can just find my dial gauge
 

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Discussion Starter · #10 ·
So I was looking some more at the timing, its still here:


__
__-------- right here is where it is at.
__
__ (outside of flywheel)
__


_____


which i thought was advanced quite a bit, but when I hit the gas it jumps down lower which would retard the timing????????? That doesn't make any sense to me?? Maybe my cdi is bad?? The stator plate is turned counterclockwise which should be advanced.
 

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Discussion Starter · #11 ·
Well I messed around with it some more today, and no matter where the stator was had no effect at all on the way it ran, it runs good when you give it more then 1/2 throttle, between 4500 to 5500 there is an occasional miss. I even put new plugs in and that still didn't change anything.
 

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Discussion Starter · #12 ·
rode it some more and it moves good, but once in awhile idling down it will back fire really loud in the pipe, sometimes in the carbs and i can feel it in the throttle, and the 4500-5500 mis is still there.
 

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Discussion Starter · #13 ·
gonna borrow a coil/cdi and see if that changes anything
 

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Discussion Starter · #14 ·
nothing changed, so im back to messing with the stator until it runs good
 

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Discussion Starter · #15 ·
found out I needed to take the flywheel off to move the stator plate, I thought it was turning but it was to hard to see.
The timing was just advanced really far, it pulled really good at wfo but less then 3/4 was not good, now its good all the time, but doesn't pull as hard.
 
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