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1989 YZ250 Won't Start - HELP!?!? !?

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1989 Yamaha YZ250


Purchased this 2 yrs ago, needed carb work and new fuel tank. Finally got around to fixing everything, now bike won't start.....I can kick and kick and kick and it WILL FIRE but will not start. Have tried pull starting it - will only start when bike is in 2nd gear and going 30-40 mph (gotta be spinning very very fast or it won't start). If in 3rd gear or going slowly then bike will fire once or twice but thats it. HELP!?!?


Here's what I've done or checked thus far:

SPARK and IGNITION

  • Has spark at the plug when turning the engine over
  • Have tried 2 different brand new plugs, both getting good spark
  • Read that ignition coils were common problem, replaced coil with brand new one but didnt change starting problems at all
  • Pulled off flywheel, woodruff key is not sheared and timing looks to be correct

FUEL

  • Cleaned carburetor (which was gunked up pretty good)
  • Made sure choke is working and no jets are plugged
  • Checked Pilot Jet, its currently a #70 (60 is stock...main jet is stock too)
  • Checked reeds, they are sitting "flush on their perch" and seem to be in good shape, look like the stock reeds
  • After kicking engine over quite a few times, the spark plug is wet with fuel
  • Have tried spraying starting fluid into the Carb, also tried gas down the plughole....this doesn't seem to help at all
  • Have adjusted air screw from 1/2 turn to 3 turns out, no difference

COMPRESSION

  • Compression is at about 190-195

OTHER

  • Using freshly mixed gas (a week ago), 32:1
  • Air filter looks good, I've also tried starting it with the airbox boot removed (to allow free-flowing air), still nothing
  • Have checked exhaust, it is not plugged at all



Any ideas on where to go next? Gotta be missing something? HELP!?

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The only thing I can think being an issue if everything else looks normal would be blown out crank seals. Whay did the old spark plug look like. Was it coverd in oil. Does the tranny oil smell of gas ? Is there oil leaking out of the stator side of the motor ?

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The only thing I can think being an issue if everything else looks normal would be blown out crank seals. Whay did the old spark plug look like. Was it coverd in oil. Does the tranny oil smell of gas ? Is there oil leaking out of the stator side of the motor ?

Spark plug looks wet, covered in gas and oil (maybe a little more oil than gas, but basically looks like pre-mixed gas). 

 

There is no oil leaking out of stator side of the motor. 

 

I can smell tranny oil for gas, haven't done that yet....thanks for the response. 

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