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Problem with initial valve adjustment after rebuild

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leadnavel:
I've been rebuilding the Engine on my 750 K7 (77) and i'm trying to set up the valve clearance, this is where i'm having the problem! When I try to set up the valve timing by the book - set the "T" mark for 1.4 with cylinder 1 at TDC and the key groove towards the top - I should be able to (if I'm reading things correctly in the workshop manual with the "O"s and "X"s diagram) set the valve clearances for INLET and EXHAUST on No.1, EXHAUST for No.2 and the INLET for No.3. This is my problem, i'm finding that I cannot set the clearance for cylinders No.2 EXHAUST and No.3 INLET as they are on the cam!


What am I doing or have I done wrong? I hope that someone out there can can advise me on what to do to put it right. I've been searching the forums but i'm either not putting the right search terms in to get a result or it's to simple an error on my part that it's not referenced! Any help that you guys could give would be muchly appreciated.

Also to note that when I rotate the crankshaft 360 to set the remaining valve clearances the same problem occurs. I can set the clearances (INLET & EXHAUST) for Cylinder No.4 but the INLET for No.2 and EXHAUST for No.3 are on cam and cannot be set!

Engine rebuild info...

My bike had previously been running. On strip down I backed off all the adjusters so I didn't have a reference from them as to where the adjusters should be. I bagged and tagged everything. Is it possible that I tagged some rocker arms incorrectly, could I have put them back in the wrong place?

When installing my camshaft/cam sprocket on the top end rebuild I had No.1 and No.4 cylinders to top-dead-centre (TDC) and aligned the "T" mark on the spark advancer also aligning the Timing index line so it was parallel to the top surface of the camshaft holder with the key groove was towards the top, so i'm thinking that I did everything correctly with the camshaft installation.

McCabe-Thiele (Ted):
I'm a novice but are you sure No1 is TDC on compression reads as though its No4 just rotate the crank another turn as cam rotates at half crank speed?


Sorry if you have eliminated this possibility.

K2-K6:
It's more a foible of the manual description and giving different information for two different tasks than anything wrong.

To set the cam originally (installation) you do as you've done with mark lining across  am carrier split, and notch at 12 o'clock.  The notch is not visible for setting tappet clearance with cover on and so not really significant.

Buuuuut, setting it like you are now with it all visible,  put the camshaft notch at the bottom 6 o'clock and it will then conform to the schematic of which valves to set clearances at.

You've not got anything wrong, just how some things are explained in the text.

K2-K6:
Adding to the above,  after you've done the #1 valves plus the others listed, turn the crankshaft one full rotation (notch will now be upward) and set the valves for #4 along with the remaining two not yet done.

That'll complete it for you.

leadnavel:

--- Quote from: McCabe-Thiele (Ted) on May 23, 2022, 10:45:30 AM ---I'm a novice but are you sure No1 is TDC on compression reads as though its No4 just rotate the crank another turn as cam rotates at half crank speed?


Sorry if you have eliminated this possibility.

--- End quote ---
When I turn on the crankshaft clockwise towards the “T”1.4 mark, the key groove is towards the top of the cam index line, I look at the exhaust valve on No.1 cylinder which is just closing, the “T” arrives at the timing mark, both INLET & EXHAUST are closed. Immediately I continue turning the crankshaft clockwise away from the “T”1.4 mark the INLET valve on No.1 cylinder starts to open.


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