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Ronny
Honda never offered an undersize bearing outer shell or pins for these cranks and the NOS one's i have, have different letters engraved on them.

As these bearings are specially modified bearings made for Honda from a standard production bearing, the modification e.g being the location pin in relation to the oil hole, for one. IAN-NTN bearings would have (assumption here) run these as a small production run and the letters identify the bearing for its location on the crank. I have bearings marked F,G,H and also marked A,B and one with D crossed out and B marked in its place :roll:

The roller bearing is generally not rebuildable, as the crank surface, pins and outer bearing all wear at different rates with the pins (rollers) wearing the quickest.

The only way to gauge the wear is to measure the crank bearing surface in several different spots and note the difference between the contact (roller contact) section and the other measured spots. Then do the same with the outer shell and finally measure the rollers and compare that with a NOS one.

Most of this information is located on the outer bearing shell, RNAO 32X72X21XPX1 or RNAO type code, outer Dia 72mm, crank Dia 32mm, width 21mm, and the final PX1 should be the tail code which gives the cage material type.

Hope this helps :D



 

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Znabb said:
How do I read this Selection table of crankshaft bearings?
F.ex. my old crank bearings is marked D. Could a slightly worn D-crank use C bearings? Am I making any sense here? :?
You don't :? These charts are for slipper bearing cranks and have no relationship with roller bearing cranks. Their purpose is to accommodate for the inconsistencies in the factory manufacturing process, which in the 1960's-70's was not that great.
So the assembly line had a "person" measuring cranks (what a job) and assigning the best bearing for the crank within a controlled tolerance :D :D

Why CMSNL have this listed with the CB/CL 450's is anyones guess :D
 

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If this confuses the discussion, please ignore it... Both my '81 Goldwing and my '89 Accord are slipper bearing engines. The Honda manuals have different letter selections for each standard and oversize bearings. Honda specifies the clearance and the bearing letter is selected to get the clearance correct.
 

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JamesPal said:
If this confuses the discussion, please ignore it... Both my '81 Goldwing and my '89 Accord are slipper bearing engines. The Honda manuals have different letter selections for each standard and oversize bearings. Honda specifies the clearance and the bearing letter is selected to get the clearance correct.
Yep :D mate no confusion, as you stated this type of "lettering" is purely for slipper bearing engines :D
 

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otr002 said:
JamesPal said:
If this confuses the discussion, please ignore it... Both my '81 Goldwing and my '89 Accord are slipper bearing engines. The Honda manuals have different letter selections for each standard and oversize bearings. Honda specifies the clearance and the bearing letter is selected to get the clearance correct.
Yep :D mate no confusion, as you stated this type of "lettering" is purely for slipper bearing engines :D
One of these days I will get into my Honda Lawn Mower and find out what kind of bearings it has :lol:
 
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