Looking for an air leak

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Sep 8, 2018
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Rebuilt 850 MKIII with new valves, etc. Good bore and pistons. New Wassell Evo carbs with 319 pilots and 260 mains. First ride out Sunday. Bike started well on choke and tickle, did not like going off choke. Horrible bog on the bottom. Same as with old carbs.
Will run on choke at low throttle only. When it gets on the main jet runs great.
I suspect an air leak. I have checked-
-Intake manifold and carb sealed with anaerobic sealant. carb tops and float bowls are tight.
-Just set the valves will check them again.
-I'm going to pinch off the balance tube on the intakes to see if it shows more on one side.
-Plugs are light tan on one side but I used the choke to get low end and take off.
-I'll spray the intake joints with ether to check for obvious leaks
-Any other places to check? Has anyone seen air leaking from the intake mounting threads on the head?
 
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May 28, 2003
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Amal 850 was 3-1/2 with 260 main...

Isn't Wassel 850 supplied 3(rich) cut away slide with 220 ? 260 would be super rich at low end/off idle.
 
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Sep 8, 2018
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Amal 850 was 3-1/2 with 260 main...

Isn't Wassel 850 supplied 3(rich) cut away slide with 220 ? 260 would be super rich at low end/off idle.
I bought these set up for a Norton. I'll have to check the slides. I have a k&N filter and peashooters on it. Pulls well once on the main jet.
 
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Apr 29, 2009
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Might try raising the needle a notch. Mines in the bottom notch (richest) on my 750 and its just on the edge of lean. Doesn't cost anything.
 
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No effect spraying on the intake joints. No effect blocking off the balance tube. I'm going to try advancing the timing. Currently Lucas Rita, may be old and not advancing properly
 
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