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Help on1987 225 moto 4

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Old 08-13-2013, 03:27 PM
storman's Avatar
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Unhappy Help on1987 225 moto 4

I got this thing not running. Took head off and intake valve bent in open position. They had taken thing apart to fix low power. Put new valve in, But.. The arrow on emergency rope pull and book say it should turn counter clockwise looking at it from left side of unit. As you start to turn from TDC position counter clock wise exhuast valve opens first on down stroke.... that ant right....Could they have mixed up valve rocker arms when they took it apart? I don't want to bend new valve.. Timing is lined up on T mark on fly wheel and line on cam gear . Does unit really turn counter clock wise from left side looking at it?? help! please
 
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Old 08-13-2013, 09:10 PM
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If the arrow and the book say it's supposed to turn counter clockwise then I would trust it. I don't see how anyone could have gotten the rocker arms mixed up but that would not make the valves open incorrectly. I would be more worried about having the correct cam installed, if it's wrong that would do what you're talking about, but that normally wouldn't happen, i'm not even sure cams could be interchangeable like that. You could always turn the engine with a wrench a couple of rotations to make sure nothing binds up, you'll know real quick if the valves hit the piston, the engine should spin fairly free. Just don't spin the engine with the starter until you know for sure everythings right. If anything is wrong, I would say it's your timing, make sure the piston is at the top by sticking a screwdriver or something down the sparkplug hole when the crank is at tdc and make sure the valves are 100% closed and have some play in the rocker arms when the piston is at tdc.

I'm a little rusty but if I remember correctly the magneto goes around twice for every one rotation of the crank, so it is possible for the "T" to show but the piston is at the bottom of the cylinder, so make sure the piston is definitely at the top when the T is visible. This would cause your timing to be 180 degrees off.
 
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