Wrist pin to connecting rod fit

According to the manual the wrist pin to connecting rod fit should be 0.003mm - 0.025mm (KZ750B)

this seems like a very wide range as 0.003mm (0.00012") is nearly a press fit. while 0.025mm (0.00098") is a floating fit. I am going to have the small end of some NOS connecting rods honed so that this tolerance is ideal with the DLC coated wrist pins I have as it is too small right now. What tolerance should I aim for to ensure good oil film? I have read that .0008" is ideal for a floating pin but that was for big V8.

thoughts?

The optimal tolerance is depandent to the connecting rod Diameter and piston bore Diameter in driving temperature condition. Parts expant with Temperature rised. A 17 mm Piston rod should have 0,005 - 0,01 mm tolerance cold. Aluminum expant more than twice as steel when going hot and the tolerance goes near to Zero.
You will see a Brown, blue, purple coloring on the Piston pin surface as a sign of heat stress.

Thanks for the reply. I'm referring to the connecting rod small end and the wrist pin not the piston.

Edit: I'm struggling with math today...

According to those specs the target clearance is between .00011-.0011"

Not sure what to suggest other than go off nominal, say .0007"

0.00011" = 0,002794 mm up to 0.0011" = 0,02794 mm tolerance min. and max. (not Service Limit)
nominal, say 0.0007" = 0,01778 mm so what´s wrong with the math?

Should aim to be in the middle of the piston to rod range then? (.025-.003)/2+.003= .014mm (.00055")

DoctoRot wrote: I have read that .0008" is ideal for a floating pin but that was for big V8.

thoughts?

Are the molecules in motorcycle oil a different size than automotive oil?


.