Quote: Has anyone considered that the "unfinished" rod journal lightening hole might be done that way to set the max. designed bobweight? If they'd punched that hole all the way through then they'd have to go back and take material off the counterweights to compensate. Am I wrong here? Let me know. Cory
This is exactly my thoughts.
My guess is they leave some weight in them because its easier to take weight out than to add weight on in the balancing process.
The holes aren't all that big either - maybe 1/2" or 5/8" - unlike a stock crank that has huge holes.
Thanks for backing me up. Though I didn't say it explicitly, what I was thinking was that, during the mfg. process they have all these cranks that are the same. Then, they want to set the up for different target max. bobweights. Say you want a max. 2300 gm BW, you drill the holes to one depth. The you want some for a 2500 gm bobweight so you drill them a little deeper. Then maybe you want some for a 2100 gm BW so you drill them a little shallower. I guess what I'm trying to say is that the amount of material drilled out could be used to tune the crank for a particular intended max BW. I wanna say that the fact that the holes aren't drilled all the way through is a non-issue. The finish on the holes is another thing. I wouldn't want any burrs falling off.
Nobody has said I'm hallucinating, yet. Well, not today anyway....
Sorry guys,call it hallucinating,wishful thinking or plain assumptions on your part.To clarify "to assume" You make an azz of you and me.That one rod journal throw was not drilled all the way for balancing purposes,it was a result of an unfinished process.In over forty years of engine building on my part and exposure to many of the greats in the industry along the way in most every type of racing that involves internal combustion engines I would characterize that as a minor fkup.Not a big issue but since the assembly was balance a costly fkup.The crank was factory balanced at 2300 grams,the actual bobweight was 2169 grams.To further define my point I will spin the crank as is,record the over or under or "perfect"balance,then I will address the rod journal and flange and spin it again.Just the fact that the bobweight dictates the crank needed lightened shoots your assumption out of the water.I sunk your battleship!!!No offence,just BGR humor
