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Why mark primary chain?

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Old Jul 1, 2023 | 07:09 AM
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Default Why mark primary chain?

Manual says you’re supposed to mark the compensator sprocket and primary chain when removing, so the sprocket is put back in the same place on the chain.

But why? The chain is much longer than the diameter of the sprocket, so different links are mating with the same sprocket tooth as it turns, so I don’t get the reasoning?

Anyone know for sure?
 
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Old Jul 1, 2023 | 07:55 AM
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the theory is keeping the same wear pattern and yes, the same teeth will engage the same roller as it goes around. however, on an oil bath chain probably not much of an issue but still exists.
a chain not under tension will set lower in the tooth if its rollers are worn, that said, when under tension, it will travel higher in the tooth limited by the pitch. roller wear does not effect pitch change but does effect how the chain set in the tooth under tension. when you start getting pin wear, that has an effect on pitch. diff between pin and roller wear.
how many follow that advice, hummmm, probably not many and shops included.
 
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Old Jul 1, 2023 | 07:56 AM
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And to revisit. Yes you do need to pull the main fuse.
 
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Old Jul 1, 2023 | 08:12 AM
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It's done to maintain direction of rotation, because of wear patterns.
 
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Old Jul 1, 2023 | 08:17 AM
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Originally Posted by bustert
the theory is keeping the same wear pattern and yes, the same teeth will engage the same roller as it goes around.
How do you figure this when some compensators are even tooth, some odd tooth?

You mark the outside of the chain, that way you won`t reinstall the chain running the wrong direction, nothing more to it.
 

Last edited by Dan89FLSTC; Jul 1, 2023 at 08:20 AM.
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Old Jul 1, 2023 | 08:48 AM
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Originally Posted by Dan89FLSTC
How do you figure this when some compensators are even tooth, some odd tooth?

You mark the outside of the chain, that way you won`t reinstall the chain running the wrong direction, nothing more to it.
I suspect this to be the case.
When I recently had my primary apart, I saw this in the manual as well, but couldn't figure out why it would make any difference if the chain slop at the top meets spec when assembled.
Since this entire assembly is unrelated to valve timing and such, I just can't understand why it would matter, other than to retain the orientation of the chain/direction of rotation.
 
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Old Jul 1, 2023 | 10:12 AM
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If it were to maintain alignment with chain/comp sprocket, why not call out marking the clutch basket too?
 
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Old Jul 1, 2023 | 10:22 AM
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Originally Posted by smitty901
And to revisit. Yes you do need to pull the main fuse.
Um, I think you have the wrong topic Sir.

Originally Posted by rigidthumper
It's done to maintain direction of rotation, because of wear patterns.
This makes sense, thank you.

Originally Posted by Dan89FLSTC
How do you figure this when some compensators are even tooth, some odd tooth?

You mark the outside of the chain, that way you won`t reinstall the chain running the wrong direction, nothing more to it.
Yep, good reasoning. I guess that’s too complicated to write in the manual, so they just write it so a monkey can follow along.
 
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Old Jul 1, 2023 | 10:25 AM
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While I do take off together, I have never put the chain back on exactly, not saying bad. I mark inside and outside. I doubt most people get the exact tooth alignment. Not that I am saying you shouldn't. But with 90k and 70k, so far so good.
 
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Old Jul 1, 2023 | 12:34 PM
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All that is needed is to install the chain in the same running direction, simple as that.

Mark it with paint, zip tie etc.

No need to mark sprocket.
 
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