"stol" wrote in message
ups.com...
I'm curious about how you have 0.4 ips vibration problem?

Pistons and rings are not part of crankshaft balance.
Pins bearings?

Let me set some things straight for ya. Any good racing machine shop
can balance a motor far better then the vast majority of FAA approved
places. In fact Lycoming can't even built a crank for some models they
produce that won't break, and they have killed people this way. So much
for the FAA keeping a close eye on quality... As for nitriting and heat
treating, this is an every day detail in the racing market and is down
to a science, not black magic... Pistons and rings and circlips are
part of the rotating/reciprocating assembly and need to be balanced
too. Good shops even add in a factor for the weight of oil that clings
to the balanced mass to get it perfect.


Well Excuse meee..........!!!!

Circlips? Are you referring to piston pin circlips? They are not used in
Lycomings or Continental aircraft engines.
Tell me which models of Lycomings break cranks? I don't want to fly behind
those.

I'm still wondering what the pin bearings are.

Please direct me to to a engineering reference or paper that discusses the
factor that discusses the weight of oil that clings to the balanced mass.
Otherwise that is somebody's guess.. their own black magic.
Kent Felkins