Why is the timing being so difficult~?~

outlawbusa

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Had a little head work done (port, polish, valve job, springs) and then I reshimmed the valve clearances. Stock cams have not been changed.

When I line up the marks on the exhaust cam it shows about 1/2 tooth off. Intake looks good and counting 15 pins on top of the chain from gear to gear.

I have taken it apart a few times but can not get it quite right. Put it together with the exhaust cam mark showing the 2 on top and the 1 just a mm below the head surface and fire it up, can hear the valves...shut it off and take it back down. If I move it a tooth it shows about 1 mm or so above the head surface.

We have all the slack out of the exhaust side and resting on the tensioner side.

Mr Brown

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Where are the marks lining up at? Not the numbers, the little dashes.

outlawbusa

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The dash on the exaust cam rests either just below or just above the head surface. Like it needs 1/2 a tooth...

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outlawbusa

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adjustable cam sprocket time

I do have that option since we do have a set of adjustable cam sprockets here, but I told my friend why put those in when the stock ones came out and should line up fine going back in?

I don't get it...would something have changed where they might not line up properly again?

smithabusa

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any idea what the numbers are now with a degree wheel? I have seen some pretty low/high from the factory

outlawbusa

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I just had a thought...is it possible the chain guide could be causing something to be out?

It slid into it's slots just fine and did not see any issues...hate to take it back down that far~!~

outlawbusa

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any idea what the numbers are now with a degree wheel? I have seen some pretty low/high from the factory

Honestly don't know...we tried it low and started it for about 2 seconds with valves clicking pretty bad.

Placed the mark in high but after the cam carriage is tightened the mark shoots even higher...haven't tried starting it like that

Mr Brown

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I changed my head gasket last weekend, lined up the mark on the starter and tried to line up the marks on the cam gears per the manual, but couldn't get them exact. Without adjustable gears, it's almost impossible. Wound up being off a tooth, corrected that and still wasn't perfect. Turned the motor over with no noise, so I buttoned it up. From what I understand, being that the bikes are assembled on a line, perfect cam timing is not something that is achievable with stock gears, as long as it's close they let them go. Did they line up perfectly before you pulled the cams, or did you not think to look like me? I was thinking maybe the cam chain stretched a little over time? If you have adjustable sprockets at your disposal, why not use them?

Mr Brown

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Honestly don't know...we tried it low and started it for about 2 seconds with valves clicking pretty bad.

Placed the mark in high but after the cam carriage is tightened the mark shoots even higher...haven't tried starting it like that
Rotate the motor off the crank with a 14 mm socket. No need to start it. You will hear any issues as it turns.

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What exactly was the process step by step that you did?

I normaly go chain on exhaust sprocket, 1 arrow/line level with head or a little above, 2 arrow/line vertical, intake sprocket arrow 3 straight up on the 15th pin.

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what did you do to the motor? If any mods etc i would think you would want to degree them in for best power.

outlawbusa

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Rotate the motor off the crank with a 14 mm socket. No need to start it. You will hear any issues as it turns.

Can turn all the way around with socket with no noise at all

outlawbusa

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What exactly was the process step by step that you did?

I normaly go chain on exhaust sprocket, 1 arrow/line level with head or a little above, 2 arrow/line vertical, intake sprocket arrow 3 straight up on the 15th pin.

Sounds right...only the exhaust arrow either goes low or way above

outlawbusa

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what did you do to the motor? If any mods etc i would think you would want to degree them in for best power.

No mods at all...just minor head work.

My friend has the adustable cams so I would only use them as a last resort...he did offer them to me.

I think they also take a special tool we do not have.

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It sucks not have adjust sprockets and a huge timing wheel... I would have to say that since you tried it low and it made noise try it high. I don't know what else you can do at this point of the assembly. :banghead:

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You did tighten the tensioner all the way in before you installed it and let it take up slack already right? Just thinking out loud here......
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