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Discussion Starter #1 (Edited)
Short Version:
I did not do a valve adjustment correctly. During the follow up compression test, I heard a loud pop from the horizontal cylinder. I re-adjusted the valve clearances. The vertical cylinder reaches 90psi, no change in wet compression test. Horizontal cylinder has no compression.


Long Version:
I misunderstood the correlation between the 'loaded gap' and the closing rocker clearance. This lead to a botched valve adjustment. During the first crank of the engine there was a loud pop from the horizontal cylinder.

I re-evaluated and I think I understand it now. Just to be sure I am understanding it here are my new clearances:

Vertical Cylinder:
Intake - Alternator Side - Loaded - 0.005in
Intake - Alternator Side - Unloaded - 0.008in
Intake - Alternator Side - Closing - 0.003in

Intake - Clutch Side - Loaded - 0.005in
Intake - Clutch Side - Unloaded - 0.008in
Intake - Clutch Side - Closing - 0.003in

Exhaust - Alternator Side - Loaded - 0.006in
Exhaust - Alternator Side - Unloaded - 0.003in
Exhaust - Alternator Side - Closing - 0.003in

Exhaust - Clutch Side - Loaded - 0.007in
Exhaust - Clutch Side - Unloaded - 0.004in
Exhaust - Clutch Side - Closing - 0.003in


Horizontal Cylinder:
Intake - Alternator Side - Loaded - 0.005in
Intake - Alternator Side - Unloaded - 0.008in
Intake - Alternator Side - Closing - 0.003in

Intake - Clutch Side - Loaded - 0.004in
Intake - Clutch Side - Unloaded - 0.007in
Intake - Clutch Side - Closing - 0.002in

Exhaust - Alternator Side - Loaded - 0.007in
Exhaust - Alternator Side - Unloaded - 0.010in
Exhaust - Alternator Side - Closing - 0.003in

Exhaust - Clutch Side - Loaded - 0.007in
Exhaust - Clutch Side - Unloaded - 0.010in
Exhaust - Clutch Side - Closing - 0.003in


The vertical cylinder has 90psi compression dry. It takes at least 5 cranks to get there. Each crank increases the pressure by 18psi. I did this test with the throttle stuck wide open and only half of the exhaust attached. Wet compression test shows same results.

I believe the belt position is correct, When the dot on the crankshaft gear lines up with the mark on the engine case the vertical cylinder white marks are nearly pointing straight up. Between the white marks are 11 belts ribs, 12 if you include one immediately over the white mark. Ther horizontal cylinder white marks are pointing opposite directions. The topmost mark is pointing straight up and the bottom mark is point toward the ground. There are 20 belt teeth between the white marks, 21 if you include one immediately over a white mark.I had to tension the belts by feel as I do not have the tool.

I'm hoping the no compression is a blow head gasket. As for the low compression I can only imagine valves, but what am I doing wrong?

I did not do a compression test before I started this project, but the bike was not running well.


***Update***
Placed hand over horizontal cylinder exhaust, and there is some suction. Hand over the throttle body, it is pushing air out. Obviously I messed up the horizontal cylinder.
 

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I would remove the head and see if you had any contact causing your loud "pop"? Sorry I'm not a lot of help on how to fix it though. Good luck and hopefully didn't mess anything up too bad.
 
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