Replacing valves shims

Eliran

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Hey all
This is my first post, so I'm hoping i go by the rules on that
Ill start by saying that I'm hoping you all will understand my English, as it is not my first language.

So the question:
I have a 1979 cb750.
I took apart the engine to replace the head gasket.
I haven't measured my valves clearance before i took it apart. So my question is do i need to resemble the engine again, check valves clearance and then replace what ever shims that are not in range? Or can i just replace all the shims by just buying new one in the default size?(if thats even make sense)

P.s
If i can have one more question
How can i measure the timing chain to know if i need to replace it?
Haven't found it in the manual

Thx in advance
 

amc49

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Look harder, the manual has it but you likely are not able to do it, not a simple task. The timing chains are not nearly so important as the tensioners are, they go out way faster.

There is NO default shim, they all are different even when brand new. Can't do it anyway, the cams will have worn making default not right. No one engine ever has all the shims exactly the same.
 

Eliran

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Look harder, the manual has it but you likely are not able to do it, not a simple task. The timing chains are not nearly so important as the tensioners are, they go out way faster.

There is NO default shim, they all are different even when brand new. Can't do it anyway, the cams will have worn making default not right. No one engine ever has all the shims exactly the same.

Thx for the answer.
Well, I've already ordered new tensioners.

For the valves, i get it. Ill just check clearance after I'll reassemble everything.

Thx again
 

user8086

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The only way to replace that timing chain properly is to split the cases,.. once you get everything reassembled you will have to check valve to shim Clearances which is basically setting valves.. A shim tool is a must a pick and a magnet.. there has been many a debate on the Clarence we now set everything at .005 cold.. the numbers on the shims are probably wore out so a decent micrometer might help and remember to put the shims number side down so you can read them in the future
 

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