B 125 piston/rod order

Anonymous-0 · Mar 8, 2014

Hey Dickl . could you take me through the proper arrangement of rods as installed in a 125 engine ? I managed to confuse myself because of: 1. Taking too long to rebuild ths engine. 2. Poor marking practices during teardown. 3.The ac book says "new replacment connecting rods are not marked , and should be installed with the wrist pin clamp bolt toward the camshaft" I am using new pistons, and the crank is new {reground}. I think I recall you explaining to someone the arrangement of long side of the rod/cap facing front or rear on the crank depending on which rod it is. Facing all wrist pin clamp bolts the same way would simplify , but is this correct? maybe i'm thinking of a different engine. Set me straight, please! Thanks.

Dick L · Mar 8, 2014

Having the wrist pin bolt the same way would never work on these engines. Looking at the bottom of the rod you can see they are all alike and are offset from the center of the rod.
Number one and two rods have the wide part of the cap facing each other. The same with three and four as you can see by the picture.

If you take care installing the piston making sure the rod on the wrist pin is centered in the piston as it goes in you will notice if it is correct that it will be centered on the crankshaft journal.

B 125 piston/rod order

Anonymous-0

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Dick L

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