Ron Tebo wrote:
> Gary:
>
> The 5 main bearing crank is nodular cast iron and would probably be less
> flexible than the 3 bearing crank both because of the extra bearings and
> because of the material and manufacture. However the drop-forged crank
> would have better shock resistance because the stress lines in the
> forging follow the shape of the crank, a result of being formed from a
> billet, rather than cast (but would flex more with fewer bearings). As
> you suggest, this may be a trade-off?
The forged 3 main would appear to be a wash as compared to the cast 5 main,
but I would submit that the rootes works teames did suffer failures from
broken cranks running the 1592.
I dont recall hearing of a broken 1725 crank.
Jarrid Gross
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