Author Topic: 100 miles after top end rebuild, need valve adjustment?  (Read 1119 times)

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Offline killersoundz

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100 miles after top end rebuild, need valve adjustment?
« on: August 16, 2012, 09:28:13 PM »
I've put about a 100 miles on my 750k4 since rebuilding the top end. It's been mixed cruising and some aggressive riding. I replaced the valve tappet screws on the rockers since the old ones were worn out. I adjusted the valve lash right to spec, I double and even triple checked it. It sounded like butter very quiet valves but they are starting to get a little nosier, is it standard procedure to need another valve adjustment after a rebuild?
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http://forums.sohc4.net/index.php?topic=107447.0

My CB750K4 Starting up for the first time after a seized motor and rebuild!


Offline dave500

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Re: 100 miles after top end rebuild, need valve adjustment?
« Reply #1 on: August 16, 2012, 11:38:50 PM »
yep and cam chain adjustment.

Offline lucky

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Re: 100 miles after top end rebuild, need valve adjustment?
« Reply #2 on: August 17, 2012, 10:00:31 AM »
Yes that is normal.
As the gaskets heat up and crush there is some slight movement.

If it is possible it is good to recheck the torque on the cylinder head studs in the proper order also.


These are normal procedures after an engine rebuild.

If you had a manual it even tells you.

Offline killersoundz

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Re: 100 miles after top end rebuild, need valve adjustment?
« Reply #3 on: August 17, 2012, 10:14:23 AM »
Yes that is normal.
As the gaskets heat up and crush there is some slight movement.

If it is possible it is good to recheck the torque on the cylinder head studs in the proper order also.


These are normal procedures after an engine rebuild.

If you had a manual it even tells you.


LOL.

Yeah there's no way to check the head stud nuts. Dang 750's with their no way to take valve cover off
My project thread:

http://forums.sohc4.net/index.php?topic=107447.0

My CB750K4 Starting up for the first time after a seized motor and rebuild!


Offline tlbranth

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Re: 100 miles after top end rebuild, need valve adjustment?
« Reply #4 on: August 17, 2012, 10:14:44 AM »
Seems to me that the cam and the rockers stay the same relative to each other on an OHC engine. On a pushrod engine the gap will close up as the head gasket compresses. Not so with OHC. However, with new screws, I'll bet they hammer down a bit, opening the gap.
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