Camshaft timing - Is my engine timed one crankshaft tooth out?

OK, a productive morning in between domestic chores.

Set up a DTI on left side inlet valve (closed). Rotated the crankshaft anticlockwise until DTI just moved. Caught it at 0.002" valve lift. The manual says the left side fully advanced timing mark is at 38 degrees btdc. The manual says the inlet valve starts to lift at 36 degrees btdc. What did I see on the timing marks?

I estimate that give or take a bit, 1 degree of crankshaft rotation is around 2mm on the timing marks of the stator. The inlet valve at 0.002" lift is showing around 36.5 to 37 degrees btdc. The manual says one tooth of mistiming results in 26 or 46 degrees opening.

Result? As near as possible to check with rudimentary tools. The camshaft timing is correct.

That leaves me wondering why I ran out of retarding adjustment at the points plate. But unless I take the motor out and disassemble to check every setting, I'm not going to answer that question. Pictures below -

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For completeness, this is a screenshot of the page in the Yamaha manual for checking inlet valve opening point with a DTI. Inlet valve opens at 36 degrees btdc. Fully advanced timing mark is at 38 degrees btdc. One tooth error in camshaft timing is 10 degrees. So it should be pretty obvious if camshaft timing is correct or not. I need to convince myself one way or the other about this. Following this procedure I think is about as quick and easy as it gets. (Now, where did I put that DTI?).

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If the intake valve starts to open at 36° btdc and the timing mark (spark) is at 38° btdc .....that doesn't sound right if that is the case if it sparks before compression or 2° after intake begins something is wrong. What is happening on the other cylinder at 38° timing? Is that where the wasted spark is? 38° seems pretty far advanced also. Even when cruising? No?
 
If the intake valve starts to open at 36° btdc and the timing mark (spark) is at 38° btdc .....that doesn't sound right if that is the case if it sparks before compression or 2° after intake begins something is wrong. What is happening on the other cylinder at 38° timing? Is that where the wasted spark is? 38° seems pretty far advanced also. Even when cruising? No?
You're forgetting the spark is every 720 degrees of crank rotation. You're confusing 38 degrees BTDC on the compression stroke and 36 degrees BTDC on the exhaust stroke.
 
Well, I thought I had all the manuals but I can't find that page you posted in post 16? What was your intake valve clearance set at when you did this test? All the early manuals I have say to set the intakes at .006", then they give a degree reading of 47 for when the valve just starts to open, not 36 like yours shows.
 
Well, I thought I had all the manuals but I can't find that page you posted in post 16? What was your intake valve clearance set at when you did this test? All the early manuals I have say to set the intakes at .006", then they give a degree reading of 47 for when the valve just starts to open, not 36 like yours shows.
This one, the procedure I show in post #16 is page 2-23 and 2-24.

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OK, I don't have that one. Is it available as a free download somewhere?
I don't have the pdf on this device. But if you message me with an email address I'll send it to you as an attachment. If it's too big as an attachment I'll work out something else. It will be a few hours now before I get home.

Edited to add - the pdf manual is 371mb, so email is not an option.
 
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I don't have the pdf on this device. But if you message me with an email address I'll send it to you as an attachment. If it's too big as an attachment I'll work out something else. It will be a few hours now before I get home.

Edited to add - the pdf manual is 371mb, so email is not an option.
You have a Google account? If you do you can put it in Google Drive and share it with a link.
 
OK, I got the manual from IBALT. It's 353MB... waaay to big to load here. I've shrunk it down to 11MB so it will load here. There's a slight sacrifice in quality, but it's still a good, usable manual.

Here ya go...
 

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