Factory steel rods

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Does anyone know the big & little end weights of the Factory racing short stroke steel rods? Some were acid dipped & failed. Any photos?
 
I wish I could help you out help here Jim, but I'm too new to Nortons to be able to offer up anything. Cj
 
Big end 385 grams, small end 145 grams. I measured this on the rods from a factory flat track bike with short stroke 750 engine. It had originally been raced by John Hately and Dave Aldana. When the NVT operaton folded here, they gave the bike to John, and I bought it from him to get the engine for my road race bike. I'm not sure, but I suspect these were the acid dipped rods, because we eventually broke one of them at an AHRMA road race in Steamboat Springs. I wouldn't recommend using those rods in any sort of serious race engine.

Ken
 
Ken,

Care to expound a bit on the mode of failure (if there was enough left to tell)?

Rod splitting @ small end?
Rod bending/breaking mid section?
Big end failure?
Pictures available?
 
When you acid dip high tensile steel, you can get hydrogen embrittlement if you don't bake the components at 180 degrees centigrade for 24 hours. If you acid treat HT bolts, or worse cadmium plate them, they often break after being tensioned for a few hours. It shouldn't be a problem to acid dip con rods. They are more likely to fail because of non-metallic inclusions in the forgings. (dirty steel from a poor process.)
 
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