964 crank-is this a std/std?
 

just measured a 964 crank that I have, the mains are 59.98 and the big ends are 55.00 is this a std/std?

Thanks,

Andy

Your crank seems stock and within the wear limit according to my Bentley Technical Manual. Page 13-4 says:

Main bearing journals 1-7
standard: 59.971-59.990mm
wear limit 59.960mm

Main bearing journal 8
standard: 30.980-30.993mm
wear limit 30.970

Connecting rod journals
standard: 54.971-54.990mm
wear limit 54.960mm

Smaller sizes in increments of .25 and .50mm indicate a modified grind.

cheers don but it would look like my con rod journals are out of spec if they are 55.0 right?

Andy

Hmmm, 55.0 is mighty close to spec. Wear would make them smaller than spec, thus requiring machining to an even smaller increment. Try measuring again after they are polished.

55.0 is less than 0.5 over the spec so I would say it's acceptable. I agree with Don.

cheers cheers Don and Iroc. looks like its a standard crank then

thanks

Andy