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Old 1989 Yamaha big bear 350 won't start


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I have an old '89 big bear 350 that I am having trouble with . I have cleaned the carb , install ed a new stator , pulsar coil , ignition coil , CDI box ,new plug ,  timing is dead on , and a new intake boot , compression test says 125 lbs . When I crank it over it will start , but won't run it acts as if it's either got a bad vacuum or compression leak or is out of time . If you have any input maybe it will help I am about out of ideas .  When I got it it was not firing and the guy said he had it idling and it just died and wouldn't start . I have ordered a new carb but have my doubt's it's going to help because this is the second carb I have cleaned and installed on it . Any Ideas ?

Edited by Samuel Jerome Morris
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  • Ajmboy changed the title to Old 1989 Yamaha big bear 350 won't start
  • 4 weeks later...

Ok  got it firing and now it will start . Problem is it just sits and kinda idles like an engine out of time and if i touch the throttle it dies immediatly . I have cleand the carb and then pulled the carb off another one i have and swapped them it runs great on the other bike and mine does the same on this one barely idles . I have checked for clogged exhaust , made sure fuel flow is good checked valve lash and timing . I am out of ideas i think i will pull the head next and check the gasket . The compression is around 130 lbs . Im lost ! Anyone got any ideas ? HELP !!! 

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