I had my crank turned because I thought that it would be a good idea to ensure a good bearing surfaces in my built DOHC ZC. I mentioned something to this extent on dseries and a couple of guys basically said that there is some special OEM finish to honda crankshafts and that having them turned is a bad idea. Does anyone have any info about this?

It would seem to me that if there was some special finish to OEM honda cranks that it would eventually wear off.

 

having the crank turned and ordering oversided bearings is standard machining practice if the journals on the crank are grooved or worn too badly for you to be able to just polish them. if you didnt run the engine without oil pressure, you could have just micro polished the journals and ordered stock size bearings. i think the "special finish" is just the polishing that is done to every crank. ---- d series.org

 

yes there is a nitride (is that the right word?) coating on the oem honda crank

 

Alright so my crank was turned .010" should I even worry about this?

 

.01"? you are gonna need some THICK bearings

 

.010" undersize turning is VERY common, on V8's.........rarely heard of it being done on Honda's since the cranks are very tough. I was told if you ---- up the crank in a Honda, better off finding a new one.

Either after turning they are not as good, or the OS bearings are junk.

 

.01 just seems like too much. considering that the bearing tolerance is like .0015. i dont think even the thickest honda bearing will correct a .0115 tolerance. or are the OS bearings you are talking about not honda?

 

usually clevite 77's for the OS bearings

 

No, I have ACL's and all of my bearings are specing out fine. I'm just curious if I need to trash this crank and buy a used one.

 

are they the oversized ACL's?