Timing Question

056F

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I'm in the middle of doing the valve check/adjustment on my '17. Everything was going fine until I forgot to put the CCT back in before turning the crank shaft to seat everything before re-measuring. The chain slipped on the sprockets so timing is shot to hell. I understand how to reset it by pulling the cam shafts and lining up the marks. I know that the crankshaft indicator is supposed to have "K" lined up with the case seam when I do this, however that happens at two points in the cycle. So the question is does it matter which of those points it's at when the cams are reinstalled (it seams like it should), and if so how can I tell when it's correct?
 

holligl

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I'm in the middle of doing the valve check/adjustment on my '17. Everything was going fine until I forgot to put the CCT back in before turning the crank shaft to seat everything before re-measuring. The chain slipped on the sprockets so timing is shot to hell. I understand how to reset it by pulling the cam shafts and lining up the marks. I know that the crankshaft indicator is supposed to have "K" lined up with the case seam when I do this, however that happens at two points in the cycle. So the question is does it matter which of those points it's at when the cams are reinstalled (it seams like it should), and if so how can I tell when it's correct?
Definitely does matter. See tip on page 5-19 of the SM. With the K at b, Piston #1 needs to be 71° before TDC on the compression cycle. If you have the plugs out, I believe others have used a screw driver or dowel to verify TDC on cylinder #1. (T mark)

Good Luck!

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holligl

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Additional thought: Maybe pm ~Tabasco to know how to verify it is the compression stroke and not the exhaust. I would say he's the expert here. I don't know what sensors trigger the fuel injection and spark.

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WJBertrand

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If the cams are completely out, I don’t think it matters if the crank was previously on an exhaust or compression stroke. The difference is defined by the camshaft phasing. It’s important that the crank and cam timing marks are all correctly positioned of course. The above only considers the mechanical details. Not sure if spark or injection timing is specific to one or the other of the two rotations though.


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056F

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Thanks everyone, It sure seems like the CAMs would need to be aligned with the when the computer fires the sparkplug/injectors. I'll keep looking...
 

056F

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After failing to find anything definitive online or in the manual that indicated it mattered I found this thread (https://www.fz09.org/threads/how-to-tell-tdc-on-compression-vs-exhaust-stroke.41426/) that talks about "wasted spark" motors. Figuring the lack of procedure in the manual (or obvious sensor) probably put it in this category as well, I put the bike back together and it fired right up. Either I got lucky (50/50 shot I guess) or it doesn't matter. I'm inclined to believe the latter. Thanks again for all your input.
 

WJBertrand

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I know some engines (my previous ST1300) have a cam position sensor so in that case it for sure wouldn’t matter, but I don’t recall seeing a cam position sensor on the super Ténéré, but I wasn’t really looking for one when I was in there.


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holligl

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I know some engines (my previous ST1300) have a cam position sensor so in that case it for sure wouldn’t matter, but I don’t recall seeing a cam position sensor on the super Ténéré, but I wasn’t really looking for one when I was in there.


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I didn't see one on the parts breakdown either.

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holligl

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After failing to find anything definitive online or in the manual that indicated it mattered I found this thread (https://www.fz09.org/threads/how-to-tell-tdc-on-compression-vs-exhaust-stroke.41426/) that talks about "wasted spark" motors. Figuring the lack of procedure in the manual (or obvious sensor) probably put it in this category as well, I put the bike back together and it fired right up. Either I got lucky (50/50 shot I guess) or it doesn't matter. I'm inclined to believe the latter. Thanks again for all your input.
I was going to suggest a 50/50 chance, if it matters, but that would be a lot of effort if you got it wrong and it did. So glad it worked out! That's one of those "I won't make that mistake again"!

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holligl

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I'm now thinking the TB injectors probably don't care about timing. Probably more continuous flow. The wasted spark ignition approach would make sense. Interesting and educational.

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056F

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I'm now thinking the TB injectors probably don't care about timing. Probably more continuous flow. The wasted spark ignition approach would make sense. Interesting and educational.

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Yeah, I had that realization as I was putting them back in, direction injection would be a different story. After this experience I may upgrade to a manual CCT too just so I never have to reset the automatic one again, I probably did it 4 times today due to a few false starts getting the timing set right.
 
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