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Have you done a thorough search for a loose shim in the head? Around the valve spring areas and under where a cam lobe might be stopped by a stray shim?

 

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How about the cam blocks? Are they different and could possibly be swapped between intake and exhaust cams?

 

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You definitely working through this and addressed a thought I had about the cam chain and guides. Look at the top of the right, #2 exhaust valve. Verify you have two valve spring keepers still in position and an equal small gap between the two keepers. Also, have you noticed the suspect exhaust valve spring retainer having a slightly different position as it sits in the head? Maybe not if a typical shim size still produces the correct clearance. Any other debris in the valve spring areas?

The other though is that as easy as the cams can be removed, you aren't that far from being able to remove the cylinder head. That would definitely reveal or clear the problem. Just need some coolant and a head gasket.

Before you started the valve clearance check and adjustment, did the engine sound ok? Or, is the check due by mileage?

 

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Yeah, I'm curious about the cause of this stoppage.

Cam timing is a real thing. Definitly get that right. Check and recheck before releasing the chain tensioner too. You can use a short tool to manual press the chain guide to be extra sure the timing is correct. Also, when checking the cam timing, don't rotate the engine backwards to check timing marks. If you have to back-up, do so enough that the crank can be rotated forward to properly take up the chain slack. Sounds like you are aware of this, so just a reminder.

If you can see the pistons through the spark plug holes, try a long piece of wire to identify the lower and higher pistons.

 

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Some good information there. Have you been able to inspect the entire cam chain? Like mark one link and pull, or rotate all the way around? The cams would have to be out to do this. Also by doing this, you could confirm the crank is capable of rotating 360 degrees.

Sounds like you have access to a borescope. Pretty cool. I haven't seen on since my Army Aviation days. Our engine mechanics had them for inspections of compressor blades--or, as they needed for troubleshooting.

 

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Interesting to hear about how there is not inspection cover for timing marks; and yeah, that's a step should be mentioned in the manual. Still it might not be necessary to remove the clutch cover to check valve clearances. Here's a tip. Watch the intake cam lobes. Once it depresses the intake valves and begins to close, that piston is on its way to TDC. At TDC, the intake and exhaust cam lobs face away from each other. It'll be a while before you have to do another valve clearance check, but you could get a piston to TDC, remove the chain tensioner, then remove the cams to replace shims and not remove the clutch cover. (never rotating the crank at that point)

As for a possible bent valve, I'd not suspect that actually happened just yet as the valve most likely made flat contact with the piston--just a stop of the rotation. You could install the cams and do a compression check. Also suspecting that everything could be buttoned-up and start the engine. Once at idle, immediately monitor the exhaust header pipes for heat build-up. The two should be equal.

 

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Got it. It's an experience. Be glad it's not a four cylinder engine. Those timing reference marks are ridiculous really. Why have two of the same? Maybe, that target is used on more than one bike engine.

So you have a valve stem lower than others and suspecting it's a bent valve? Does the engine really have to be removed in order to remove the cylinder head? Maybe the front of the engine could be lowered enough to remove the head?

If you have to replace a valve and don't have a spring compressor, maybe an auto parts store has one to loan. A c-clamp version would be easiest. I used to have one, but when I left the tech industry that was one tool I let go. Haven't had a need for it since either.

 

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Definitely a lot going on there, huh? It's been a awhile since I had to remove an engine--the GPz750turbo I got back in '00. The frame was bent at the steering head. The price for that head seems good.

Can't help but notice you have a several irons in the fire around your shop. And with style given the rugs.

 

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Has the replacement head been delivered? Hopefully it is as expected for you. Also, if upon removal of the head and you see the valves are seated as they should, would you correct what you saw from the top side and reinstall it?

 

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Does it come with the cam blocks too? They are supposed to be a match set due to the line-boring.

 

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The other two the locate on the dowel pins. The ones you mentioned are marked "intake" and "exhaust."

 

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I can inquire to the seller but you're saying not to install the new head if I can't also get the missing intake and exhaust blocks/caps?

The heads are sold with the blocks and there is no part number for the blocks.

There's a possibility that your head and the one being shipped were bored with the same boring bar; so, maybe the bore diameters are the same. Next would be to ensure the alignment of your cam blocks to the new head and how to do that would take a few minutes of thought. Then, to ensure enough clearance for oil, Plastigauge should be used. That will tell you the clearance. You could even check what your current head has for clearance and compare to the head enroute. Would have to reference a manual for a clearance range.

Or, you could get a valve spring compressor and simply use the parts from the arriving head and repair what your current head needs.

 

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Glad you are out riding! Bike looks good too.