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Discussion Starter · #1 ·
I'm reassembling my top end and I have trouble adjusting the valve clearance on the LH exhaust valve. According to the Clymer manual the pin on the camshaft and the "L" on the sprocket should both be pointing up when the "LT" line on the rotor aligns with the timing mark. After I install the the rocker arms and cam lobes, then rotate the engine to make sure its all OK, I can never get that to line up again.

Anyone have any suggestions, or am I missing something? thanks
 

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Sensei
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It would be easier to answer if we knew which engine we were discussing....year, size, model, etc....
 

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Discussion Starter · #4 ·
Hi everyone. I posted the original question. The bike is a 72 CB350 K4 twin. I've replaced the valves, rings, honed the cylinder, and had my machine shop assure me the mating surfaces are flat.

Any help would be appreciated. thanks
 

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Sensei
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ALL the timing marks/indicators SHOULD align EXACTLY at least once every TWO full rotations of the crankshaft (the full four strokes) ...IF they don't, you do have a problem......You may be trying to "set" the index marks on the exhaust stroke rather than the compression stroke.............
 

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Discussion Starter · #6 ·
I think I have a more fundamental issue. I've been doing this with the cam case cover off to make sure everything was lined up in there. When the cover is off not everything is tightened down. When I crank the crankshaft around, on both intake strokes (left and right) the whole cylinder/cylinder head/cam case assembly wants to lift about 1/16" off the engine block in order for me to complete the turning of the crankshaft. If I screw the cam case cover down tight I cannot even complete a turn around on the crankshaft rotor.

I have a lot of experience with two stroke and pushrod engines, so these OHC engines are new to me. The new valves I installed (from Sirius Consolidated in Canada) were exactly the same length and size as the original ones I removed. The cam chain tensioner and roller are new too.

Does anyone have any suggestions? thanks
 

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You may have bent your new valves messing about like that.......
However, the cam timing is not set on compression stroke - the valve clearances are.

We'd still appreciate it if you added the requested info to your signature.
 

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Discussion Starter · #8 ·
I'll take them out and check, I hope I didn't bend anything. Any idea what could be causing this? I followed the Clymer instructions.
 

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Sensei
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You missed step 19 (page 77, bottom of left-hand column).........
 
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