DO I NEED NEW PISTONS?

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DO I NEED NEW PISTONS?

RodneyCB750K1979
I measured the outside diameter of the pistons using a dial vernier caliper. I measured two places at the top and bottoms of each piston. I verified the accuracy of my instrument by measuring the outside diameter of one of the wrist pins at its center (.590 inch measure versus .5903-.5906 factory specs).

The following are the piston diameter measurements.  

ALLOWABLE DIAMETER IS 2.439 TO 2.440 WITH A 2.437 LIMIT

                                               PISTON 1       PISTON 2        PISTON 3       PISTON 4
Piston Dia @ Top Pin - Skirt    2.416 - 2.417    2.415 - 2.415    2.415 - 2.416    2.416 - 2.415
Piston Dia @ Bot  Pin - Skirt    2.431 - 2.438    2.429 - 2.439    2.429 - 2.438    2.428 - 2.438

Should I replace these pistons?  The bike has 23,000 miles.
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Re: DO I NEED NEW PISTONS?

TOOLS1
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You will just fine with new rings, and honing the cylinders.
TOOLS
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1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
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