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Hi All, One easy way to verify you are very close is to use go/no go feeler blades.

So for .004 spec use the .004 (or use rotation of screw method). Then verify with a .003 feels sloppy, .005 will not go it without undue force. Go/no go verification makes it almost impossible to be too far out. If.... you have access for feeler blade.

Very simple for bikes with direct access with feeler gauge such as ones with feeler access hole on side of rocker box, or with valve covers like later 650 & T140.

Ace Hardware in USA sells a feeler set. The thinnest is .0015 which will feel loose with an .002 spec. Then use the .003 for no go. It also includes a brass .010" blade which is handy for checking rotor/stator gap.

I get it is very very hard to get blade into the valve stem with 650 screw on caps. Angle of rotation is good enough if you can't get feeler in.

Regarding valve adjustment being so far off to not have compression, I'd wager the opposite like valve was not fully opened. It is critical to have motor in correct position. Meaning when one intake valve is fully open, adjust the other. Put bike in gear & rock rear wheel with finger on rocker arm & you'll soon feel what I mean. Then rotate motor & adjust the other valve. Then do same for exhaust, one fully open, adjust the other.

One little thing that can happen is you remove spark plug & some carbon breaks off from threads. It gets trapped in valve seat & holds valve open slightly. You feel clearance & it's loose so you adjust to spec. Starting motor the carbon blows out of seat, now valve is fully closed leaving it too tight.

Triumphs can/will do this, but are not prone to it. (some motors are very prone to this). The cure is don't remove spark plugs before valve adjustment even though motor is hard to turn over. Or... Loosen plugs 1 turn, reinstall plug caps & start motor. Blip throttle several times to like 3000 rpm. Remove plugs, let motor cool all day or overnight, then adjust valves. Either of these assures carbon will not interfere with accurate valve adjustment.

I've been tracking my valve adjustment from new. Most interesting how little they change. Usually less than .001 in 3k miles. I decided to let it go 5k miles last time. Still within .001". This is with the last 23k miles on California unleaded fuel.
Don
 

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Interesting. I will see how mine sound after setting up. I need to find out what clearances I need for the Hyde tappets and half-race cams first though... I don't seem to have that info.
 
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